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EYEPIECE
Journal of the Amateur Astronomers Association of New York
August 2012
Volume 61 Number 8 ISSN 0146-7662
Hiding in Plain Sight - Discovery of
Higgs Boson Excites Physicists
Dark Energy - Emerging From the Dark
By Evan Schneider
By Alan Rude
“We observe in our data clear signs of a new particle, at the level of 5
sigma, in the mass region around 126 GeV.” Fabiola Gianotti, noted Italian
astrophysicist and leader of the CERN ATLAS project; July 4, 2012
In the 1990’s, two competing groups of astrophysicists were working to measure the deceleration of the expansion of the universe. It seemed to be intuitively apparent that
while the expansion had been known since Hubble, there
should be a deceleration due to the lessening pull of gravity.
Just as a ball thrown upward will lose velocity (and even reverse course and come back to Earth), so too the universe
would lose expansion velocity and might even fall back in on
itself in a reverse Big Bang.
The two competing teams worked with Type 1a super
novae which are “standard candles,” very much like Cepheid
variables, but have a far greater intrinsic brightness. These can
be observed at vast distances in galaxies billions of light-years
away. The two teams’ data concurred, showing that the 1a
supernovae were dimmer than expected and therefore farther
away. This supported the theory that the universe’s expansion
was speeding up at far distances. The name given to the force
causing this was “dark energy” to sound like the mysterious
“dark matter.” However it was not like dark matter at all.
Dark energy completes the cosmic puzzle (at least
through 2012) in the model that is known as “Concordance
Cosmology.” Dark energy is evenly distributed and not
clumpy like dark matter and is not diluted in the accelerated
expansion as are matter and energy. Cosmologists have calculated that it comprises 70% of the universe’s mass/energy.
Normal matter and energy (baryonic) are estimated to be 5%
and the remaining dark matter accounts for the balance of
25%. This construct fits a wide variety of observed data relating to galactic rotation, gravitational lensing, primordial nucleosynthesis, and the cosmic microwave background.
History is made every day, but in the world of astrophysics, achieving illusive goals utilizing highly complex
equipment is a labor of love and extreme dedication. On July
4, the world reverberated with the announcement of the discovery of the Higgs boson particle, the final missing ingredient
in the Standard Model of particle physics and a milestone
event that will reveal how mass is formed in the universe.
The Higgs boson was first postulated in 1964 by British
theoretical physicist Peter Higgs, but it was not until 1976 that
CERN’s Professor John Ellis suggested that the research
should be put to the test. What followed was 36 years of conception and construction of the Large Hadron Collider (LHC)
built to create the ideal conditions to produce evidence of this
particle. The theory proposed that a “Higgs energy field” exists everywhere in the universe. As particles zoom around in
this field, they interact with and attract Higgs bosons, which
cluster around the particles in varying numbers, forming mass.
The Atlas project, staffed by 300 scientists and led by
astrophysicist Fabiola Gianotti, was the focal point of this research initiative. Located in a 17-mile tunnel beneath the
Franco-Swiss border near Geneva, Switzerland at a cost of $10
billion, the collider contains 1200 magnets cooled to -271C,
which accelerate protons to 99.9% of the speed of light. At this
speed the protons then ‘collide’, creating thousands of new
particles. Physicists estimate that for every billion collisions 10
Higgs bosons are created.
“The Higgs boson is the last missing piece of our current understanding of the most fundamental nature of the universe."“
Physicist Martin Archer, Imperial College, London
Sean Carroll, theoretical physicist at Caltech provided
more clarity: “As successful as the Standard Model has been,
we know it's not the final answer to how the universe works.
Strong evidence comes from the existence of dark matter:
mysterious, invisible stuff that adds up to five times as much
mass as the ordinary atoms and particles in the universe. But
we're trying. Multiple experiments are underway to look for
the dark matter particles we think are all around us.
Higgs Boson continued on page 3
Photo Credit Above: Large Hadron Collider, CERN
Although we can surmise that dark energy is smoothly
spread throughout the universe and very constant in time, we
have very little idea of its composition. Quantum mechanics
(QM) offers the best current explanation of its nature. Vastly
simplified, QM states that it is impossible to make space perfectly empty - that even in the emptiest state there will be
(virtual) particles that will pop in and out of existence. This is
predicted by QM and effects of these virtual particles have
been observed. They constitute what is called “vacuum energy,” the leading candidate for quantum physicists’ definition
of dark energy.
Dark Energy continued on page 4
EYEPIECE
WHY WE EXPLORE
August 2012
Human Space Exploration
By Amy Wagner
Humanity's interest in the heavens has been universal
and enduring. We are driven to explore the unknown, discover
new worlds, push the boundaries of our scientific and technical
limits - and then push further. The innate desire to explore and
challenge the boundaries of what we know and where we have
been has provided significant benefits for centuries.
Human space exploration addresses fundamental questions about our place in the universe and the history of our
solar system. Through acknowledging challenges inherent in
this endeavor, we expand technology, create new industries,
and help foster a peaceful connection with other nations. Curiosity and exploration are vital to the human spirit. Exploring
deep space will invite nations of today and generations of tomorrow to join NASA on this exciting journey.
A Flexible Path
This is the beginning of a new era in space exploration.
NASA has been challenged to develop systems and capabilities required to explore beyond low-Earth orbit, including destinations such as near-Earth asteroids and eventually Mars.
The International Space Station (ISS) is our test bed and
stepping stone for the challenging journey ahead. By building
upon what we learn, our astronauts will train to endure the
physical challenges of long duration flight and permanent expansion beyond where we have previously travelled. Explorers
may first visit near-Earth asteroids to provide valuable mission
experience and prepare us for the next inevitable step - the first
human exploration of Mars.
Robotic exploration continues to deliver profound answers about our universe, visiting far off destinations, providing reconnaissance, and collecting scientific data. When combining both human and robotic exploration criteria, we will
merge technology and our senses to increase the ability to observe, adapt, and uncover new knowledge to support future
endeavors in space.
Why the International Space Station?
The first step in embarking on a long and challenging
journey involved laying a solid foundation for a successful
mission. The International Space Station (ISS) serves as a national laboratory for human health, biological and materials
research, space technology development, and as a platform for
pushing farther into
our solar system.
On the ISS, we improve our “living in
space” techniques,
ensuring that astronauts are safe,
healthy, and productive while exploring, and expand
our
knowledge
about how materials
and biological
Dragon Capsule Docks With ISS (NASA, 2012)
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systems behave outside the influence of gravity.
NASA will continue its unprecedented partnership with
the commercial industry to support private companies developing and operating safe, reliable, and affordable systems to
transport crew and cargo to and from the ISS and low-Earth
orbit. This key to the success of future solar system missions.
Why Asteroids?
Asteroids are believed to have formed early in our solar
system's history - about 4.5 billion years ago - when a cloud of
gas and dust called the solar nebula collapsed and formed our
Sun and planets. By visiting these near-Earth objects to study
the original solar nebula material, we will answer some of humankind's most compelling questions: How did the solar system form and where did the Earth's water and other organic
materials such as carbon originate from?
In addition to unlocking data about our solar system, asteroids will provide new information about our planet. A
greater understanding about asteroids will reveal more about
past Earth impacts, providing us with methodologies to reduce
the threat of future encounters with near Earth objects (NEOs).
New NASA robotic missions to asteroids and private
enterprise initiatives by companies like Planetary Resources
will prepare humans for long-duration space travel and the
eventual journey to Mars. Robotic missions will also provide
reconnaissance information about asteroid orbits, surface composition, and even return samples to Earth for further evaluation. These are critical steps in preparing humans to visit asteroids where we will learn about the valuable resources available
in space and further develop ways to use them in our quest for
more efficient and affordable exploration.
Why Mars?
Mars has always been a source of inspiration for explorers and scientists alike. Robotic missions have found evidence
of water, but biological life beyond Earth still remains undiscovered. The remote exploration of Mars has revealed characteristics and a geological history similar to Earth, but scientists
know that there are ever greater differences waiting to be uncovered. Humans can build upon this knowledge base, search
for signs of life, and investigate Mars' geological evolution.
A mission to our nearest planetary neighbor provides the
best opportunity to demonstrate that humans can live for extended, even permanent, time beyond low-Earth orbit. The
technology and systems required to transport and sustain explorers will drive innovation and encourage new ways to address the multitude of logistical challenges. As previous space
endeavors have demonstrated, the resulting ingenuity and technologies will have long-lasting benefits and applications.
The impetus to travel to Mars and learn how to live on its
surface will encourage nations around the world to work together to achieve such an ambitious undertaking. The ISS has
shown that opportunities for collaboration will highlight our
common interests and provide a global sense of community
achievement. ■
EYEPIECE
Higgs Boson - continued from page 1
Not only are they "dark," these particles hardly interact with
ordinary matter at all. The Higgs boson could be the bilingual
particle we've been looking for. We don't know exactly what
dark matter is, but we certainly have our favorite theories. In
many of those models, the Higgs is the one particle that readily
interacts both with ordinary protons and neutrons and also with
dark matter.”
Now that scientists have discovered the Higgs boson particle, they must study its properties - how it is made and how it
decays into other particles. Then their next goal will be to produce dark matter in the LHC, another historic and monumental
achievement. It won't be easy, because dark matter interacts so
weakly. Even if it can be made, it's hard to be sure, because the
antisocial dark matter particles tend to zip out of the experiment without leaving any trace behind.
Regardless of the time it takes to move science to the
next level, these efforts have significant impact to humankind’s understanding of how the universe was formed and
where it is going. So quick, look around you - can you see the
Higgs bosons now? ■
The Ring of Fire from the Grand Canyon
By Tony Hoffman
On May 20 I drove north with friends I’d been staying
with in Sedona, to Moran Point on the South Rim of the Grand
Canyon for the annular solar eclipse. This relatively secluded
lookout still drew a substantial crowd. The weather was perfect, cloudless and with steady seeing despite the Sun's relatively low altitude. I had brought my Personal Solar Telescope
(PST) as well as my Canon T2i digital SLR with a 75-300mm
lens and a Thousand Oaks R-G filter; we also had eclipse
glasses.
I set up at one edge of the parking lot, behind a low wall
away from the canyon rim
(as we had a very inquisitive 2-1/2-year-old girl
with us). This site (by and
large) provided a good
balance between conducting my own observations/
photography and being
able to share the view in
the PST with passersby.
I took my first shots
shortly after first contact. I
ended up taking a lot of
August 2012
images with the Canon
(with focal length set at
300mm), and also some
shots with a camera held
to the eyepiece of my
PST. Just before sunset, I
took some unfiltered pictures of the Sun (with a
bite still taken out of it)
sinking into the canyon.
I’m glad, though, that I
also took some time to just
gaze at the Sun in eclipse glasses and in my PST, especially
during the annular phase.
At the onset and end of annularity the display of Baily’s
beads was impressive -I was a little surprised at how jagged
the Moon’s limb seemed to be.
It was a beautiful event, my first successful viewing of a
central solar eclipse -I had been clouded out during the total
phase of the 2009 solar eclipse from Shanghai -and at a perfect
location (though not on the centerline). I can also safely discard the notion that I am somehow among the eclipse
“jinxed”. It’s whetted my appetite for eclipse viewing, and
look forward to my first successful viewing of a total solar
eclipse perhaps as early as 2015.
Tony Hoffman is an active
observer, astrophotographer,
AAA board member, Managing
Editor for PC Magazine, and
writer for Sky & Telescope, as
well as other publications.
Photo Credits:
Tony Hoffman, 2012
Eyepiece Staff - August Issue
Editor
Evan B. Schneider
Writing Staff: Richard Brounstein, Joseph Fedrick, Tony Hoffman,
Stan Honda, Amy Wagner
Special Sections: Marcelo Cabrera, Joshua Erich, Edward Fox,
Richard Rosenberg
Kleegor’s Universe
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EYEPIECE
WHAT’S UP IN THE SKY
AAA Observer’s Guide for August 2012
By Richard Rosenberg
August’s Evening Planets: Mars and Saturn are the only
bright planets in the evening, but a lot happens this month.
Mars rapidly approaches Saturn and the bright star Spica. On
August 21 the Moon joins them. Watch their positions change
night-to-night.
August’s Evening Stars: August’s constellations include
the Summer Triangle containing the bright stars Vega, Deneb
and Altair, in Lyra, Cygnus and Aquila respectively. Low in
the south are Scorpius and Sagittarius. Starting to get low in
the west is Arcturus, the bright star of Boōtes. Look east to
spot Pegasus, the first hint of autumn.
August’s Morning Planets: Dominating the morning sky are
Jupiter, Venus, and (later in the month) Mercury. Jupiter rises
at 2 AM early in August and at midnight at month’s end. It’s
in the constellation Taurus. Venus comes up at 3 AM all
month, moving into Gemini during August. Mercury can best
be seen between August 11 and 25 low in the eastern sky.
August’s Morning Stars: The constellations of winter are at
their best. Look one or two hours before dawn to view Orion,
Taurus, Gemini, Auriga, Procyon, Canis Minor and Canis
Major.
August’s “Skylights”
August 1
August 9
Full Moon at 11:27 p.m. (EDT)
Last Quarter Moon at 2:55 p.m. (EDT)
August 11
Moon is 5¼° upper right of Jupiter and 5½°
above Aldebaran, the bright star of Taurus.
These form an equilateral triangle
August 12
Perseid meteors peak this morning
August 13
Moon is 4° above Venus in the morning sky
In the evening sky, Saturn is 2¾° above Mars,
which in turn is 1¾° above Spica. A beautiful
threesome
August 14-20 Look for Mercury in the east a half hour before sunrise.
August 15
Venus is at greatest western elongation from
the Sun (46°)
August 16
Mercury is at greatest western elongation
from the Sun (19°)
August 17
New Moon at 11:54 a.m. (EDT)
August 21
Four bright objects appear in a close gather
ing! From the Crescent Moon, go 2½° upper
right to Spica, then 4½° above Spica to Saturn
and see Mars 4¼° lower left of Saturn
August 24
Moon is 4¾° above Antares this morning
First Quarter Moon at 9:54 a.m. (EDT)
Neptune at opposition
August 31
Full Moon at 9:58 a.m. (EDT)
For additional information visit: www.aaa.org/month1208
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August 2012
Dark Energy - continued from page 1
We can calculate the likely total universal amount of vacuum energy from quantum fluctuations which gives 10¹¹² per
cubic centimeter, an absurdly large number. This compares
with the observed density of dark energy (observed through
gravitational effects) of 10⁻⁸ per ccm. This enormous difference is called the “cosmological constant problem,” which no
cosmologist knows how to solve. Several theories address this
problem, one of which is the leader, quintessence. Quintessence proposes that dark energy is not vacuum energy after all
but is the result of an undiscovered bosonic field, analogous to
an electromagnetic field. Details are sketchy at this point, but
one of the chief sub-theories is that quintessence is slowly
changing, is not associated with vacuum energy, and therefore
would constitute no cosmological constant problem.
There is another problem, or in this case a scandal - the
“Coincidence Scandal.” The energy density of matter and
dark energy in the present universe are approximately equal,
but they have not been equal forever. As stated above, dark
energy has a constant density while matter (dark and baryonic)
is diluted away as the universe expands. Therefore, in the
young universe, matter predominated and in the future, dark
energy will be the most abundant. The “scandal” arises in that
that we are here to observe, at the balancing point between
dark energy and matter. This is the best possible time for us, in
that we are not adversely affected by either the super-dense
matter/radiation in the earlier universe or by the Big Rip, the
final pulling apart by dark energy of everything, at the end. It
gives us a special place in the evolving universe which we
have not had since we were dethroned by visionaries of science, Copernicus and Galileo.
With the recent confirmation of the existence of the
Higgs boson, further testing and results from the Large Hadrons Collider at CERN are eagerly awaited in the hope of
shedding more light on dark energy and these problems which
it has raised. ■
Nebula of the Month: Trifid (M20)
Situated in Sagittarius, approximately 5,200 lightyears from Earth, the Trifid Nebula displays a threelobed appearance.
First identified by Charles Messier in 1764, this beautiful object consists of both
emission and reflection nebulae. The red emission nebula
with its young star cluster
near its center is surrounded
by a blue reflection nebula
which is particularly conspicuous to the northern end.
The object is an unusual combination of an open star cluster, an emission nebula (the
lower red portion), a reflection nebula (the upper blue
portion), and a dark nebula
(the apparent 'gaps' within the
emission nebula that cause
Above Photo: NASA Spitzer Space Telescope
the Trifid appearance).
(False Color Image)
EYEPIECE
August 2012
A Message from AAA President Marcelo Cabrera
Hello Members:
Summer is here and our observing sessions are a lot of fun! Check out our summer schedule on the AAA website. If you
haven't been out observing yet, join us at the many places we meet around the city to stargaze. Bring your scope or binoculars and
learn more about the night sky as you observe with our trained observers.
Do you want to volunteer and help organize a couple of social events for the AAA? We are looking for a dedicated person to
help organize future informal gatherings for club members as a part of our program to bring members together. Please email me if
you would like to join our team.
Our AAA Spring/Summer Class is nearing its successful seven session run. Fifty-two members, some joining AAA for the
first time, have shared in a unique and exciting experience. We are already planning the Fall/Winter class sessions, which will
provide two individual opportunities to join us at our midtown training center – one class covering a multitude of subjects and
speakers, and a second class focusing on a single subject of interest. Watch the AAA website and Eyepiece for more information
in early September.
Remember - we now accept membership payments and donations online. New logo merchandise is also available online.
Enjoy the summer night sky!
Sincerely,
Contacting AAA
Marcelo Cabrera
President, AAA
[email protected]
Membership: [email protected]
Eyepiece: [email protected]
General Club Matters and Observing: [email protected]
Telephone: 212-535-2922
Website: www.aaa.org
Getting Ready For Curiosity’s “Seven Minutes of Terror”
NASA's most advanced planetary rover, Curiosity,
follows its course for an August 5 landing beside a Martian
mountain to begin two years of unprecedented scientific detective work. However, getting the rover to the surface of Mars
will not be easy.
"The Curiosity landing is the hardest NASA mission ever
attempted in the history of robotic planetary exploration," said
John Grunsfeld, associate administrator for NASA's Science
Mission Directorate, at NASA Headquarters in Washington.
"While the challenge is great, the team's skill and determination give me high confidence in a successful landing."
The Mars Science Laboratory (MSL) mission is a precursor mission for future human mission to Mars. President
Obama has set a challenge to reach the Mars in the 2030s.
To achieve the precision needed for landing safely inside
Gale Crater, the spacecraft will fly like a wing in the upper
atmosphere instead of dropping like a rock. To land the one
ton rover, an air bag method used on previous Mars rovers will
not work. Mission engineers at NASA's Jet Propulsion Laboratory (JPL) designed a "sky crane" method for the final several
seconds of the flight. A backpack with retro-rockets controlling descent speed will lower the rover on three nylon cords
just before touchdown, drop the rover safely and then speed
upward and away to crash land on the Martian surface far
away.
During a critical period lasting only about seven minutes,
the MSL spacecraft carrying Curiosity must decelerate from
about 13,200 mph (about 5,900 meters per second) to allow
the rover to land on the surface at about 1.7 mph (three-fourths
of a meter per second). Touchdown is scheduled for approxi-
mately 1:31 a.m. (EDT) Aug. 6.
"Those seven minutes are the most challenging part of
this entire mission," said Pete Theisinger, JPL's MSL project
manager. "For the landing to succeed, hundreds of events will
need to go right, many with split-second timing and all controlled autonomously by the spacecraft. We've done all we can
think of to succeed. We expect to
get Curiosity safely onto the ground, but there is no guarantee.
The risks are real." ■
Artist's concept of Mars Science Laboratory Curiosity entry, descent and landing
Image credit: NASA/JPL-Caltech
5
EYEPIECE
WHAT IF???
Science Fiction Inspires Science
By Richard Brounstein
If you’re reading this newsletter, then I already know
you’re a fan of science. But there’s a significant chance that
you enjoy science fiction as well. Many science fans, even
scientists, are drawn to the world of sci-fi. We love the dramatized stories of relationships and conflicts in a technologically
advanced future, or travelling in spacecraft through the cosmos
at unimaginable speeds, or living in a space colony on an alien
planet. We like experiencing natural disasters, alien attacks,
and strange astronomical phenomena. We want to observe
human society’s courage and strength when encountering advanced alien technologies.
From good science fiction (“2001: A Space Odyssey”) to
bad (“Armageddon”), we want our dramatic stories end happily. We also want a good looking hero and an attractive heroine. Sci-fi is fun and entertaining, but it also provides benefits
for technology, science, and exploration that might be lost if
we didn’t have these “inventions of the imagination.”
Inspire others to study science
Most people first spark an interest in science from books,
television and movies. Fiction draws in audiences by being
easy understandable while providing fun and excitement.
More people would rather watch a riveting space adventure,
say, human explorers discovering rare minerals on a distant
planet, than read the data from a NASA mission. The fictional
story allows people to easily relate to the exploration theme
and thus improves overall understanding on a broader basis.
Through the imagination of writers and movie makers,
we can transition from a great fictional adventure to a desire to
learn more about our universe. Consider the impact on people
watching the movie “Contact,” where radio astronomers first
communicate with an alien civilization. We see one of the
astronomers travel through a wormhole to the center of the
galaxy - much more fun to watch than reading about how SETI
looks for alien life. At SETI, mathematicians write computer
programs to analyze thousands of radio frequencies at once,
looking for tiny patterns in the data, possibly a candidate signal of alien origin. Not as exciting as wormhole travel,
though. Once deeply involved, working on science becomes a
thrilling adventure of the mind, but a strong fictional story
stays with us from the start.
Report science results to the community
Sci-fi effectively communicates astronomical discoveries
to the public. Why else does the science community give
6
August 2012
nicknames to discovered celestial objects? In 1980, Voyager 1
made the first close observations of Saturn’s moon, Mimas. A
large crater was discovered on the surface. The moon resembled the large space station from “Star Wars.” Today, the
moon is referred to as the “Death Star.” The same was true for
Kepler16b, an extrasolar planet orbiting a distant binary star
system. This discovery was nicknamed “Tatooine,” also from
Star Wars. Who can forget the image of Luke Skywalker
watching the two suns setting? NASA scientists must find a
double sunset across a desert plain much more exciting than an
artist’s concept of a remote star system and a planet.
NASA knows how to use science fiction to get the general public interested in new discoveries and space science. If
not for the use of science fiction films, these discoveries would
not be so prominent in public media.
Inspires exploration and technology
Consider the advanced technologies developed after conceptualization in, “Star Trek.” Did the communicator inspire
the invention of cell phones? Did the BIO bed inspire noninvasive and non-surgical diagnostic techniques? Consider
other “Trekkian” technologies like tricorders, holodecks, ION
propulsion, androids, matter-antimatter energy systems, artificial eyes and interstellar spacecraft. These are all technological concepts now embraced by the scientific community. Star
Trek fans are also responsible for the first NASA space shuttle
orbiter being named “Enterprise.” Yes, sci-fi and a motivated
public are definitely intertwined.
Did the 1902 Georges Méliès science fiction film, “Le
Voyage Dans la Lune” inspire US scientists to choose the
Moon as the goal to beat the Russians in the space race? Or
perhaps it was the 1865 Jules Verne novel, “From the Earth to
the Moon?” Before anyone could decide to make the attempt,
someone had to first imagine it. I’m grateful for these nonscientist authors who could imagine what must have seemed
impossible in their time.
The good and the bad
Sci-fi can also affect humanity in negative ways. In the
1938 Orson Welles radio broadcast, “The War of the Worlds,”
the public developed a sudden interest in Mars and possible
existence of alien life. This sparked fear and panic rather than
scientific curiosity. People listened to a fictional Martian attack that some believed to be real. Why do people always
assume that aliens are evil in nature? Because history has
taught us that less advanced civilizations always suffer during
encounters with more powerful forces.
Once advanced, high-speed aircraft and space exploration
became a technological fact, many sightings of unidentified
flying objects were assumed to be extra-terrestrial life forms
visiting Earth. Where did people get all of these ideas? From
the many science fiction books and movies about hostile
aliens, of course. Without science fiction, people would interpret lights in the sky as messages from heaven or atmospheric
phenomena. If we didn’t have sci-fi, I would miss the little
green men. ■
EYEPIECE
August 2012
AAA BRIEFS IN ASTRONOMY
Carrying a Heavy Load
Astrium Space Transportation and OHB of Germany
will lead two consortia to perform the design of a new heavylift launch vehicle for the European Space Agency (ESA) following a bidding competition that included a surprise third
bidder in Reaction Engines Ltd. of Britain. The new bid requests permit the industrial teams to design their own rockets
without worrying about which government will contribute to
it. Jean-Jacques Dordain, ESA Director General, stated that the
primary goal is a vehicle that will not need support payments
under normal operations once it has proved its design. If the
result is a rocket built almost entirely by just one or two nations, so be it. These nations would then be asked to finance it.
ESA officials have been spooked by Space Exploration Technologies Corp. (SpaceX) of Hawthorne, Calif., which has demonstrated its technical prowess with the launch of its Falcon 9
rocket and Dragon space capsule to the ISS in May. SpaceX
officials say one of the keys to its success is that Falcon 9 is
built in one factory owned by SpaceX. The rocket design
sought by ESA would place satellites weighing between 6,600
and 14,300 pounds into geostationary transfer orbit, the destination of most telecommunications satellites.
Pump up the Volume
Researchers
at Caltech and NASA/JPL have developed a new type of amplifier for boosting electronic signals.
The device can be used for everything from studying stars,
galaxies, and black holes to exploring the quantum world and
developing quantum computers. "This amplifier will redefine
what it is possible to measure," says Caltech’s Jonas Zmuidzinas, the chief technologist at JPL and a member of the research
team. An amplifier is a device that increases the strength of a
weak signal. "Amplifiers play a basic role in a wide range of
scientific measurements and in electronics in general," said
Peter Day, a principal scientist at JPL. "For many tasks, current amplifiers are good enough. But for the most demanding
applications, the shortcomings of the available technologies
limit us."
Caltech and JPL researchers say their new amplifier,
which is a type of parametric amplifier, combines the best features of other amplifiers. It operates over a frequency range
more than ten times wider than other comparably sensitive
amplifiers, can amplify strong signals without distortion, and
introduces nearly the lowest amount of unavoidable noise. In
principle, the researchers say, design improvements should be
able to reduce that noise to the absolute minimum. The team
recently described the new instrument in the journal Nature
Physics. One of the key features is that it incorporates superconductors - materials that allow an electric current to flow
with zero resistance when lowered to certain temperatures. For
their amplifier, the researchers use titanium nitride and niobium titanium nitride, which have just the right properties to
amplify the weak signal. The team says that the instrument can
directly amplify radio signals from faint sources like distant
galaxies, black holes, or other exotic cosmic objects. Boosting
signals in millimeter to submillimeter wavelengths (between
radio and infrared) will allow astronomers to study the cosmic
microwave background and to peer behind the dusty clouds of
galaxies to study the births of stars, or probe primeval galaxies. The team has already begun working to produce such devices for Caltech's Owens Valley Radio Observatory (OVRO)
near Bishop, California. These amplifiers could be incorporated into telescope arrays like the Combined Array for Research in Millimeter-wave Astronomy at OVRO, of which
Caltech is a consortium member, and the Atacama Large Millimeter/submillimeter Array in Chile. Instead of directly amplifying an astronomical signal, the instrument can be used to
boost the electronic signal from a light detector in an optical,
ultraviolet, or even x-ray telescope, making it easier for astronomers to tease out faint objects. Because the instrument is
so sensitive and introduces minimal noise, it can also be used
to explore the quantum world. For example, Keith Schwab, a
professor of applied physics at Caltech, is planning to use the
amplifier to measure the behavior of tiny mechanical devices
that operate at the boundary between classical physics and the
strange world of quantum mechanics. The amplifier could also
be used in the development quantum computers - which are
still beyond our technological reach but should be able to solve
some of science's hardest problems much more quickly than
any regular computer.
More Ice With Your Chondrites?
Scientists have long believed that comets and a type of
primitive meteorite called “carbonaceous chondrites,” were
sources of early Earth's volatile elements. Understanding the
origins is crucial to determining how water and life formed.
New research focuses on frozen water distributed throughout
much of the early solar system, but probably not in the materials that aggregated to initially form Earth.
The evidence is preserved in comets and water-bearing
carbonaceous chondrites. Carnegie Institute findings contradict
theories about these bodies, suggesting that meteorites and
asteroids are the most likely sources of Earth's water. Looking
at the ratio of hydrogen to deuterium in frozen water, scientists
can project distance from the Sun. Objects farther out have
higher deuterium content than objects that formed near the
Sun. Objects formed in like regions have like compositions.
Comparing deuterium content of water in carbonaceous chondrites to comets, suggests forming in similar regions.
7
EYEPIECE
August 2012
AAA BRIEFS IN ASTRONOMY
Size Does Matter
Three on a Quasar
The European Southern Observatory (ESO) plans to
build the largest optical/infrared telescope in the world. At its
meeting at the ESO Headquarters in Garching, Germany, the
ESO Council approved the European Extremely Large Telescope (E-ELT) Program. The E-ELT will start operations early
in the next decade. Upon completion, this will be the world's
biggest eye on the sky. The E-ELT will be a 39.3-metre segmented mirror telescope sited on Cerro Armazones in northern
Chile, close to ESO's Paranal Observatory. The telescope has
an innovative five-mirror design that includes advanced adaptive optics to correct for the turbulent atmosphere, providing
exceptional image quality. The main mirror will consist of
almost 800 hexagonal segments, each 1.4 meters across. The
gain is substantial - the E-ELT will gather 15 times more light
than the largest optical telescopes operating today. To take
advantage of this unique science machine, sites in the northern
and southern hemispheres have been carefully analyzed, with
the final decision settling on Cerro Armazones in the Atacama
Desert, Chile. The E-ELT will be a valuable tool in the quest
for exoplanets orbiting distant stars. This will include not only
the discovery of planets with Earth-like masses using indirect
measurements of the wobbling motion of stars perturbed by
the planets that orbit them, but also the direct imaging of larger
planets and possibly even the characterization of their atmospheres. The E-ELT's suite of instruments will allow astronomers to probe the earliest stages of the formation of planetary
systems and detect water and organic molecules in protoplanetary discs around newly forming stars. Thus, the E-ELT will
answer fundamental questions regarding planet formation and
evolution and bring us one-step closer to answering the question: Are we alone?
Scientists using three telescopes spaced thousands of
miles apart have caught the best look ever of the center of a
distant quasar, an ultra-bright galaxy with a giant black hole at
its core. By linking powerful radio telescopes in Chile, Arizona and Hawaii, astronomers created a deep-space observing
system with two million times sharper vision than the human
eye, which gave them the most detailed direct view ever of a
supermassive black hole inside a galaxy five billion light-years
from Earth. The telescopes revealed a fresh look at the flatspectrum radio-quasar 3C 279, a galaxy in the constellation
Virgo that scientists classify as a quasar because it shines ultra
-bright as massive amounts of material falls into the giant
black hole at its core. The black hole is about one billion solar
masses, with the linked-up telescopes providing details down
to a resolution of one light-year or less. The new view utilized
interferometry, "a remarkable achievement for a target billions
of light-years away," explained ESO researchers. "The observations represent a new milestone towards imaging supermassive black holes and the regions around them." ESO’s facility
in Chile is home to the Atacama Pathfinder Experiment telescope used in the quasar study. The other two instruments included the Submillimeter Array in Hawaii, and the Submillimeter Telescope in Arizona. [What Does Quasar 3C 279
Really Look Like (Video)] Altogether, the telescope array
reached a resolution of just eight billionths of a degree arc in
the night sky. For comparison, your closed fist held out at
arm's length covers 10 full degrees in the sky.
Pluto Moons NASA
Pluto's newly discovered fifth moon could mean more
debris surrounding the icy dwarf planet, which could pose a
hazard for NASA's New Horizons spacecraft launched in 2006
with the aim of mapping Pluto's surface. On July 11, researchers using NASA's Hubble Space Telescope announced
the detection of P5, a tiny moon measuring just 6 to 15 miles
in diameter. P5 brings Pluto's known satellite tally to five, and
it comes just a year after Hubble spotted moon number four,
the similarly diminutive P4.These two recent discoveries show
that the Pluto system is more crowded than scientists had
thought. So NASA's New Horizons spacecraft, which is due to
fly by the dwarf planet in 2015, may have to watch its step.
The concern is not necessarily that New Horizons will slam
into a Pluto moon that has thus far eluded detection. The probe
is traveling so fast that a particle the size of a BB could destroy
it, so researchers are worried about the broad debris field
that Pluto's moons may have spawned. "Every new satellite is
a debris producer," according to New Horizons principal investigator Alan Stern, of the Southwest Research Institute in
Boulder, Colo. “When these moons suffer impacts,” he explained, "the ejecta goes into orbit around Pluto, and so the
more satellites, the more concern we have." Adding a moon,
though, does not help poor Pluto . It remains a dwarf planet.
8
Artist’s Concept of Quasar 3C 279
Illustration Credit: ESA/M. Kornmesser
Earth Gets a Coronal Mass Ejection
Earth experienced a geomagnetic storm, between July
14-16, which happens when Earth’s magnetosphere quickly
changes shape and size in response to incoming energy from
the Sun. The energy came from a July 12 X-class solar flare.
The storms create aurorae visible at lower latitudes. STEREOB (Solar Terrestrial Relations Observatory) observations show
that the CME was traveling at over 850 miles per second. The
X1.4 class flare erupted from the center of the Sun, peaking on
July 12, 2012 at 12:52 PM EDT. It erupted from Active Region 1520 which rotated into view on July 6.
EYEPIECE
August 2012
AAA BRIEFS IN ASTRONOMY
Stardust Memories
The Dark Galaxies Rise
Astronomers report a baffling discovery never seen
before: an extraordinary amount of dust around a nearby star
has mysteriously disappeared. "It's like the classic magician's
trick - now you see it, now you don't," said Carl Melis of UC
San Diego and lead author of the research. "Only in this case,
we're talking about enough dust to fill an inner solar system,
and it really is gone!" "It's as if the rings around Saturn had
disappeared," said co-author and UCLA physics professor
Benjamin Zuckerman. "This is even more shocking because
the dusty disk of rocky debris was bigger and much more massive than Saturn's rings. The disk around this star, if it were in
our solar system, would have extended from the Sun halfway
out to Earth, near the orbit of Mercury." The research on this
cosmic vanishing act, which occurred around a star some 450
light years from Earth, in the direction of the constellation
Centaurus, appeared July 5 in the journal Nature. "A perplexing thing about this discovery is that we don't have a satisfactory explanation to address what happened around this star,"
said Melis. "The disappearing act appears to be independent of
the star itself, as there is no evidence to suggest that the star
zapped the dust with some sort of mega-flare or any other violent event." Melis describes the star, designated TYC 8241
2652, as a "young analog of our Sun" that only a few years ago
displayed all of the characteristics of "hosting a solar system in
the making," before transforming completely. Now, very little
of the warm, dusty material thought to originate from collisions of rocky planets is apparent. The dust had been present
around the star since at least 1983 (no one had observed the
star in the infrared before then), and it continued to glow
brightly in the infrared for 25 years. In 2009, it started to dim.
By 2010, the dust emission was gone; the astronomers observed the star twice that year from the Gemini Observatory in
Chile, six months apart. An infrared image obtained by the
Gemini telescope as recently as May 1 of this year confirmed
that the warm dust has now been gone for two-and-a-half
years. "We were lucky to catch this disappearing act," Zuckerman said. "Such events could be relatively common, without
our knowing it."
Dark galaxies are small, gas-rich galaxies in the early
universe that are very inefficient at forming stars. They are
predicted by theories of galaxy formation and are thought to be
the building blocks of today's bright, star-filled galaxies. Astronomers think that they may have fed large galaxies with
much of the gas that later formed into the stars that exist today.
Because they are essentially devoid of stars, these dark galaxies don't emit much light, making them very hard to detect. For
years astronomers have been trying to develop new techniques
that could confirm the existence of these galaxies. Small absorption dips in the spectra of background sources of light
have hinted at their existence. However, this new study marks
the first time that such objects have been seen directly. "Our
approach to the problem of detecting a dark galaxy was simply
to shine a bright light on it." explains Simon Lilly of the Zurich Institute for Astronomy, and co-author of the paper. "We
searched for the fluorescent glow of the gas in dark galaxies
when they are illuminated by the ultraviolet light from a
nearby and very bright quasar. The light from the quasar
makes the dark galaxies light up in a process similar to how
white clothes are illuminated by ultraviolet lamps in a night
club." The team took advantage of the large collecting area and
sensitivity of the Very Large Telescope (VLT), and a series of
very long exposures, to detect the extremely faint fluorescent
glow of the dark galaxies. They used the FORS2 instrument to
map a region of the sky around the bright quasar HE 01093518, looking for the ultraviolet light that is emitted by hydrogen gas when it is subjected to intense radiation. Because of
the expansion of the universe, this light is actually observed as
a shade of violet by the time it reaches the VLT. "After several
years of attempts to detect fluorescent emission from dark galaxies, our results demonstrate the potential of our method to
discover and study these fascinating and previously invisible
objects," says Sebastiano Cantalupo (UC, Santa Cruz), lead
author of the study. The team detected almost 100 gaseous
objects which lie within a few million light-years of the quasar. After a careful analysis designed to exclude objects where
the emission might be powered by internal star-formation in
the galaxies, rather than the light from the quasar, they finally
narrowed down their search to 12 objects. These are the most
convincing identifications of dark galaxies in the early universe to date. The astronomers were also able to determine
some of the properties of the dark galaxies. They estimate that
the mass of the gas in them is about one billion times that of
the Sun, typical for gas-rich, low-mass galaxies in the early
universe. They were also able to estimate that the star formation efficiency is suppressed by a factor of more than 100 relative to typical star-forming galaxies found at similar stage in
cosmic history. "Our observations with the VLT have provided
evidence for the existence of compact and isolated dark
clouds. With this study, we've made a crucial step towards
revealing and understanding the obscure early stages of galaxy
formation and how galaxies acquired their gas," concluded
Cantalupo. The MUSE integral field spectrograph, which will
be commissioned on the VLT in 2013, will be an extremely
powerful tool for the study of these objects.
Image at Left:
The large red circle
indicates Quasar
HE0109-3518. The
faint images from
the glow of 12
“dark galaxies” are
labeled in the
smaller blue circles.
Photo Credit: ESO, Digitized Sky Survey 2 and S. Cantalupo (UCSC)
9
EYEPIECE
August 2012
FOCUS ON THE UNIVERSE
Night Sky Photography Techniques
By Stan Honda
Now that the transit of Venus and annular eclipse are
over, it’s time to go back to night sky photography and talk
about a few things only touched on in previous columns.
Focusing can be quite difficult in the dark and with
faint subjects. A bright moon is large enough to focus on and
sometimes Venus works, but often it is too small. Sometimes
you can use an artificial light on the horizon, but individual
stars and the Milky Way are too faint for the camera to detect.
What to do? Begin by placing your camera on a tripod as if you are shooting a scene. It’s best to use a manual
focus setting if you have one. You could also try to autofocus
on the Moon or a bright distant light and then switch off the
autofocus, which would lock in your target.
If you can manually focus, start with the distance
indicator on the lens at infinity, since everything we see in the
sky is basically at infinity. Then shoot a test picture. It doesn’t
have to be a long exposure, just enough to show some detail.
Look at it on the screen on your camera. If you can enlarge
part of the image to single out a few stars, that will be a more
accurate way to see if everything is in focus.
If the image looks blurry, adjust the lens slightly towards the first numerical setting on the lens. Then take more
test pictures until you’re satisfied that the stars are sharp. Use a
small piece of masking tape to secure the focusing ring onto
the lens so it doesn’t move. You can then position your camera
to capture night landscapes. You shouldn’t have to refocus
since nothing is moving toward or away from you.
If you don’t have an external trigger or intervalometer
to fire the camera, the camera’s self-timer is a handy device.
It’s often used as a delay so photographers can get into their
own photos. But it also can start the exposure so you don’t
have to touch the camera. With less movement of the camera,
the pictures will be sharper. Set the shutter speed on its longest
timer setting, usually 30 seconds. Set the self-timer to five
seconds or the default setting, push the button to start it, and
the camera will fire by itself.
A camera that you can adjust manually allows you to be
more creative. Everything that is shot at night is usually at the
widest f-stop and longest exposure, which is easier to do with
a manual setting. Newer cameras with menus of settings for
portraits, landscapes and close-ups may include one for night
landscapes. Try that and see if it works. If you can adjust the
color balance setting, change it from Auto to Daylight - or the
setting with a Sun icon. That way you won’t get too many
variations from one photo to the next in case there are artificial
lights nearby.
Someone asked a great question at the AAA Night Sky
Photography class last month - how to prevent dew on the
camera lens? As with telescopes, condensation can form on
camera lenses. I saw a nice solution to the problem on a night
sky photography website - disposable hand warmers. You can
use a rubber band or tape to attach the hand warmer to the barrel of your lens. It will keep the glass in the lens a few degrees
10
above the ambient temperature so dew doesn’t form. And it’s
inexpensive.
Another topic we discussed at the class was electronic
noise. The one drawback to digital cameras is that if you take
very long exposures or shoot at high ISO settings, you see a lot
of “noise,” which shows up as colored speckles in the dark
parts of the image. Unfortunately for our night sky photos, we
need long exposures at high ISOs. Many cameras have “high
ISO” and “long exposure noise reduction” settings in their
menus. The first setting will work most of the time; the second
one only works for single shots, not when you are doing a series of images to make a star trail photo. But if you’re doing a
landscape with just the Milky Way or a star field, then the long
exposure noise reduction generally works well.
Subject matter is often the hardest issue to deal with.
What makes a good picture? Well, the landscape part is determined by your physical location. The sky, of course, changes
from month to month. Most Eyepiece readers know what’s up
at night or how to find out. Conjunctions of the Moon and Venus or Jupiter often make great photos. Knowing when the
Milky Way will rise or how high it will be can make planning
your shooting session easier. The lunar phase will also have a
big impact on your decisions. By using all of the astronomical
information available, you will be able to plan out a good observing and photographic session. ■
Stan’s friend
Rush observes the
sky and doubles as
night landscape
for his Petrified
Forest shoot
(Arizona, 2012)
The image was
taken with a
Nikon D3S camera using a 16mm
fisheye lens and
set for a one minute exposure at
f2.8, ISO 1600
Stan Honda is an accomplished professional photographer
and contributing writer for Eyepiece. In this continuing series of
articles, he shares his extensive knowledge of photographic equipment and techniques.
Please visit www.stanhonda.com or submit your photography
questions to [email protected].
EYEPIECE
August 2012
Calling All Telescopes…..Calling All Telescopes
Donate to Support AAA Outreach Programs
Dear Members,
Many of you have telescopes and other astronomy-related equipment (eyepieces, filters,
etc.) that are no longer being used. Most likely, you have upgraded to better equipment and
just couldn’t part with your old scope. Now there is a way to clear out your closet, get an
IRS donation receipt for 2012 taxes and make a difference by supporting our AAA Outreach
Program and students who are developing their interests in astronomy.
Consider donating your used telescope to the AAA. As a 501C3 Not for Profit, we will
provide you with documentation to submit for tax purposes.
Once your scope is received, our members will make any necessary repairs to bring them
up to observing specifications and use them for our outreach programs for schools around the
city. We may also store these scopes close to the Highline and other AAA observing sites,
making it possible for the public to use them as surprise adjunct observers. If this initiative is
extremely successful, we may offer select scopes up for auction to the highest bidder at our
annual AAA membership meeting to raise money for other club activities.
Please think seriously about giving that telescope that’s in your closet or laying on the
floor under the bed a new lease on life and contact us today.
To quote Galileo: “A telescope is a terrible thing to waste.”
If you would like to participate in this program contact Michael O’Gara at [email protected] or Marcelo Cabrera at [email protected].
Thank you in advance for thinking of others.
Michael David O'Gara
AAA Board Member
11
EYEPIECE
An Intimate Portrait of
the Solar System
By Tony Hoffman
In
Lives of the Planets: a
Natural History of the Solar System
(Basic Books, $16.99), Richard
Cornfield, a research fellow at Oxford, presents a detailed account of
what humans have learned about the
planets from ancient times into the
space age. This lively and informative tale combines history, science,
personal anecdotes, the stories of some of the scientists (both
well-known and obscure) who contributed to our knowledge of
these worlds, and details the unmanned missions to the planets
and what they have discovered.
The book’s first chapter is devoted to the Sun and begins
at Stonehenge, describing how 50 years ago American astronomer Gerald Hawkins deduced its role as an astronomical computer, with concordances going far beyond the position of sunrise on Midsummer’s Day. This is followed by a description of
the Sun as a star, its formation and future (with a discussion of
the Hertzsprung-Russell diagram), an account of Galileo’s
studies of sunspots; the cyclicity of sunspots and its possible
effects on Earth’s climate, and brief descriptions of the space
probes that have studied the Sun.
The book then moves outward from the Sun, devoting a
chapter to each planet, including one for the asteroid belt.
Cornfield focuses on the uniqueness of each world (or moon),
stressing how they’re not mere points of light in the sky anymore but destinations we have visited (or are about to visit)
with unmanned missions. In that regard, Lives of the Planets is
a fitting title, given that life, its origins, and the search for life
in the cosmos is an integral part of the story. Conversely,
Cornfield also expresses his disappointment and frustration,
where he deems the Viking Mars-landing missions “…one of
the most noble failures in the history of space exploration….”
for its inability to find any traces of Martian life. Though Viking’s biology experiments were an important aspect of the
mission, the primary goal was to provide geological and thermal reconnaissance for future missions.
In Lives of the Planets, Cornfield has done a good job in
bringing our solar system alive to the reader, weaving a combination of science, history, biography, and the latest results
from space probes together into an eminently readable and
informative narrative.
Astronomical Fact of the Month
Were you wondering how far is the nearest
star? Well, apart from the Sun, the nearest star is Proxima
Centauri, a red dwarf star located at a distance of 4.24 lightyears away (27 trillion miles ) and approximately 14.5% the
diameter of the Sun. It would take our fastest spacecraft more
than 50,000 years to make the journey. The second nearest
stars are also in the Centauri system. They’re Alpha Centauri
A and B, located about 4.36 light-years from Earth. Plan on
visiting all three on your next galactic tour.
12
August 2012
AAA Spring/Summer Class
Wraps Successful Session
By Evan Schneider
On 7/25, the AAA Spring/Summer class session completed the classroom portion of the program with an amazing
and informative interactive presentation by AAA member and
NASA/JPL ambassador, Jason Kendall. Sporting 3D glasses,
the class was taken to the surface of Mars at our high tech
meeting facility in midtown, peering down craters and across
the Martian landscape, contemplating the upcoming historic
landing of Mars Science Laboratory rover Curiosity at 1:30
a.m. (EST) on Aug 6. From there, we travelled through the
known universe utilizing the data set from the Sloan Digital
Sky Survey and reached the edge of the Big Bang and studied
the intricacies of the Cosmic Microwave Background (CMB)
in great detail.
The class was comprised of seven sessions, five of which
were held in midtown and one at the Hubble Planetarium in
Brooklyn, a small facility where Marc Horowitz provided his
own personal tour of the universe in a small dome setting using Hayden Planetarium software. A final class session (one
of our “away missions”) will be held on Aug 13 when class
members travel to Ward Pound Ridge Reservation in Westchester for a “graduation” star party observing session under a
dark sky.
There were many excellent presentations during the term,
including AAA member/professional photographer Stan
Honda (see Stan’s column, “Focus on the Universe,” in this
issue of Eyepiece) who shared his experiences, photographic
techniques, showing us space shuttle launches and the recent
Venus transit and annular eclipse . Peter Tagac, the Urban Astronomer, brought his observing equipment and aerial views of
Central Park to demonstrate line of sight for viewing the Manhattan night sky. Dr. Denton Ebel, Curator of Meteorites at
AMNH was our premiere speaker, discussing his research and
passing around small meteorites that found Earth in their path.
With Curiosity bearing down on
Mars, an intimate evening with Andrew
Kessler, the author of “Martian Summer,” brought the Mars Phoenix rover
mission to life for us all. We experienced the excitement of finding water
ice on Mars and the personalities of the
mission engineers through Mr.
Kessler’s eyes. The class enjoyed firsthand access to someone who spent
three months on “sol time,” the time
used to track the Martian solar day.
The AAA Education Committee is preparing to serve up two classes for the Fall/Winter
season. They will run concurrently at the midtown Cicatelli
Associates Training Center at 35th Street and Eighth Avenue.
One will be a single subject astronomy course for those who
are looking for a more focused experience. The second will be
a diverse program of multiple subjects and presenters. Watch
for an email notification in September, the AAA website and
future issues of Eyepiece for developing information.
EYEPIECE
August 2012
PROJECT 1640 SIFTS THROUGH STARLIGHT TO REVEAL NEW WORLDS
AMNH, which optically dims the star but not other celestial
advanced telescope imaging system that started
objects in the field of view; a spectrograph built by AMNH
taking data last month is the first of its kind capable of spotting
and Cambridge University that records the images of other
planets orbiting suns outside of our solar system. The collabosolar systems in a rainbow of colors simultaneously; and a
rative set of high-tech instrumentation and software, called
specialized wavefront sensor built at JPL that is imbedded in
Project 1640, is now operating on the Hale telescope at the
the coronagraph and senses imperfections in the light path at a
Palomar Observatory in California after more than six years of
precision of a nanometer.
development by researchers and engineers at the American
Although the coronagraph creates an “artificial eclipse”
Museum of Natural History, the California Institute of Techinside Project 1640, blocking the bright light emanating from
nology (CIT), and JPL. The project’s first images demonstratthe star, about half of a percent of that light remains in the
ing a new technique that creates extremely precise “dark
form of a bright speckled background superimposed on the
holes” around stars of interest were presented in July at the
solar systems of interest. Each of these speckles can be hunInternational Society for Optics and Photonics Astronomical
Telescopes and Instrumentation meeting in Amsterdam by Ben
dreds of times brighter than the planets .
R. Oppenheimer, an associate curator in the Museum’s DepartProject 1640, however, has now demonstrated a techment of Astrophysics and principal investigator for Project
nique to darken the speckles beyond any previous capability,
1640.
carving a dark square in
the speckle background
Although hundreds of
centered on the star. The
planets are known from
dark region can only be
indirect detection methods
created by measuring and
to orbit other stars, it’s
controlling distortions in
extremely difficult to see
the distant star’s light,
them directly in an image.
caused by traveling
This is largely because the
through the atmosphere
light that stars emit is tens
and optics, at the 5of millions to billions of
nanometer level. Previtimes brighter than the
ously, the dark hole created
light given off by planets.
by the Project 1640 tech“We are blinded by
nique had only been obthis starlight,” OppenBefore
and
after
images
showing
the
success
of
the
new
array
served
under laboratory condiheimer said. “Once we can actutions.
Now,
the
effect
on
an
actual
star has been observed
ally see these exoplanets, we can determine the colors they
through
a
telescope.
emit, the chemical compositions of their atmospheres, and
“High-contrast imaging requires each subsystem perform
even the physical characteristics of their surfaces. Ultimately,
flawlessly and in complete unison to differentiate planet light
direct measurements, when conducted from space, can be used
from starlight,” said Richard Dekany, the associate director for
to better understand the origin of Earth and to look for signs of
instrumentation at Caltech Optical Observatories. “Even a
life in other worlds.”
small starlight leak in the system can inundate our photodetecEven though the scientists are imaging what are considtors and pull the shroud back down over these planets.”
ered relatively nearby stars - those no more than 200 light
Now that the full system is working, the researchers have
years away - an extraordinary level of precision is needed to
started a three-year survey, to image hundreds of young stars.
produce accurate results.
“The more we learn about them, the more we realize how
“Imaging planets directly is supremely challenging,” said
vastly different planetary systems can be from our own,” said
Charles Beichman, executive director of the NASA ExoPlanet
JPL astronomer Gautam Vasisht. “All indications point to a
Science Institute CIT. “Imagine trying to see a firefly whirling
tremendous diversity of planetary systems, far beyond what
around a searchlight more than a thousand miles away."
was imagined just 10 years ago.”
Project 1640 is based on four major instruments that imThe planets orbiting these bright stars are the size of
age infrared light generated by stars and the warm, young
Jupiter, too hot for life to exist, though it’s possible that other
planets orbiting them. The instruments are now in operation
planets or moons in these systems could harbor life. One of the
and producing some of the highest contrast images ever made,
biggest research potentials is to unlock knowledge about what
revealing celestial objects 1 million to 10 million times fainter
the architectures of solar systems say about our own planet.
than the star at the center of the image.
“In order to understand the origin of Earth, we need to
The core of this technical advance is the coordinated opunderstand the origin of planets in general,” said Lynne Hileration of: the world’s most advanced adaptive optics system,
lenbrand, an astronomy professor at CIT. “How do they form,
built at Caltech and JPL, which manipulates light by applying
how do they evolve? How does our solar system with both gas
over 7 million active mirror deformations per second with a
giant and rocky small planets compare to others? These are
precision level better than 1 nanometer - about 100 times
smaller than a typical bacterium; a coronagraph, built at
questions that are very important to humanity.” ■
13
An
EYEPIECE
August 2012
Peering Into the Heart of a Supernova: How to Detect a Rapidly Spinning Stellar
Each century,
on average, two massive stars in our
own galaxy explode, producing magnificent supernovae.
These stellar explosions send fundamental, uncharged particles
called neutrinos streaming our way, and generate ripples in the
form of gravitational waves in the fabric of space-time. Scientists are waiting for the neutrinos and gravitational waves from
about 1,000 supernovae that have already exploded at distant
locations in the Milky Way to reach us. Here on Earth, large,
sensitive, neutrino and gravitational wave detectors have the
ability to observe these respective signals, which will provide
information about what happens in the core of collapsing massive stars just before they explode.
If we are to understand that data, however, scientists will
need to know in advance how to interpret the information the
detectors collect. To that end, Caltech researchers developed a
computer simulation of what may be an unmistakable signature of a feature of such an event: if the interior of the dying
star is spinning rapidly just before it explodes, the emitted neutrino and gravitational wave signals will oscillate together at
the same frequency.
The above image taken from the video simulation shows
the inner regions of a collapsing, rapidly spinning massive
star. At t=0, the inner core "bounces" and a protoneutron
star is made that violently oscillates, leading to a characteristic signature in gravitational waves and neutrinos. The
colors indicate entropy, which roughly corresponds to heat
- red regions are very hot, while blue regions are cold. This
frame shows about 10.44 milliseconds after the stellar core
has become a dense proto-neutron star.
Watch a video of the simulation.
(Credit: Simulation: Christian Ott, Visualization: Steve Drasco)
14
"We saw this correlation in the results from our simulations and were completely surprised," says Christian Ott, an
assistant professor of theoretical astrophysics at Caltech and
the lead author on a paper describing the correlation, which
appears in the current issue of the American Physical Society
journal Physical Review D. "In the gravitational wave signal
alone, you get this oscillation even at slow rotation. But if the
star is very rapidly spinning, you see the oscillation in the neutrinos and in the gravitational waves, which very clearly
proves that the star was spinning quickly - that's your smoking
gun evidence."
Scientists do not yet know all the details that lead a massive star (one that is at least 10 times as massive as the Sun) to
become a supernova. What they do know (which was first hypothesized by Caltech astronomer Fritz Zwicky and his colleague Walter Baade in 1934) is that when such a star runs out
of fuel, it can no longer support itself against gravity's pull,
and the star begins to collapse in upon itself, forming what is
called a proto-neutron star.
There needs to be some mechanism - what scientists refer
to as the "supernova mechanism" - that completes the explosion. But what could revive the shock? Current theory suggests
several possibilities. Neutrinos could do the trick if they were
absorbed just below the shock, re-energizing it. The protoneutron star could also rotate rapidly enough, like a dynamo,
to produce a magnetic field that could force the star's material
into an energetic outflow, called a jet, through its poles,
thereby reviving the shock and leading to explosion. It could
also be a combination of these or other effects. The new correlation Ott's team has identified provides a way of determining
whether the core's spin rate played a role in creating any detected supernova.
Ott's team happened across the correlation between the
neutrino signal and the gravitational wave signal when looking
at data from a recent simulation. Previous simulations focusing
on the gravitational wave signal had not included the effect of
neutrinos after the formation of a proto-neutron star. This time
around, they wanted to look into that effect.
"To our big surprise, it wasn't that the gravitational wave
signal changed significantly," Ott says. "The big new discovery was that the neutrino signal has these oscillations that are
correlated with the gravitational wave signal." The correlation
was seen when the protoneutron star reached high rotational
velocities - spinning about 400 times per second.
Future simulation studies will look in a more fine-grained
way at the range of rotation rates over which the correlated
oscillations between the neutrino signal and the gravitational
wave signal occur. Hannah Klion, a Caltech undergraduate
student, will conduct that research this summer as a Summer
Undergraduate Research Fellowship student in Ott's group.
When the next nearby supernova occurs, the results could help
scientists explain what happens in the moments right before a
collapsed stellar core explodes.
Article Credit: Kimm Fesenmaier, Caltech
EYEPIECE
AAA Events on the Horizon
August 2012
Tuesdays, August 7, 14, 21, 28 8:30 - 10:30 p.m., P, T, C
Observing on the High Line, Manhattan
Enter at 14th Street
Next dates: Tuesdays in September
Thursdays, August 2, 9, 16, 23 Dusk - 10:00 p.m., P, T, C
Movies With a View/Observing
Pier 1, Brooklyn Waterfront
Movie Info: gonyc.about.com
Observing: aaa.org/movieswithaview
Next dates: Thursdays in September
Wednesday August 8, Dusk
11 p.m., P, T, C
Observing at Prospect Park, Brooklyn
Next date: Visit AAA website for details
Saturday, August 18
6:30 p.m. P, T, C
Observing at Great Kills Gateway National Park, Staten Island
Next date: September 15
Wednesday, August 22, 8:30
11 p.m., P, T, C
Observing at Brooklyn Heights Promenade,
At end of Montague Street
Next date: September 19
Saturday, August 25
10 a.m. - noon, P, T, C
Solar observing in Central Park,
At the Conservatory Water
Next date: September 29
Monday, August 28
6:30 p.m., P
Astronomy Live - Sky to Space
AMNH Hayden Planetarium Space Theater
Friday, August 31
Observing in Carl Schurz Park
Next date: September 28
Legend for Events
M: Members
P: Open to the public
8:30 - 11 p.m., P, T, C
T: Bring telescopes, binoculars, etc.
C: Cancelled if cloudy
For the latest information about all AAA events,
visit our website at www.aaa.org.
International Observe the Moon Night Coming
September 22, 2012
Want
to look at the Moon? Go outside at night and
look up. It’s easy. You don't
need super advanced technology
to gaze up at the wonder that is
Earth's natural satellite. Watch
next month for events surrounding this yearly tribute to our
neighbor in the sky. This event is
sponsored by NASA’s Lunar
Reconnaissance Orbiter that just
returned images of the flag
planted by the Apollo missions!
Credits for August Eyepiece Issue
Page 3 - “Kleegor’s Universe”
Joshua M. Erich Website: (www.pixelatedparchment.com)
August 2012
Observers Log: Venus and Jupiter
Emerge in the Morning Sky
By Joe Fedrick
I awoke early on June 27 to see in the bright twilight
to my northeast that Jupiter and Venus had emerged onto the
morning sky. I had last seen Jupiter in early April when its
north equatorial belt was rather narrow and faded, something I
had not seen in 40 years of observing Jupiter. Venus, of
course, I had last observed on June 5 as it transited across the
solar disk.
Jupiter and Venus were still rather low near the horizon
in less than optimal view, but Jupiter revealed a rather odd
pattern of cloud belts in my 60mm refractor at 100x. The normally dark orange-brown north equatorial belt was still a
somewhat faded gray-tan. It had partially merged with one of
the north temperate belts to create a rather broad new equatorial-temperate belt, parallel to the southern belt and much
wider.
Venus was a rather thin, large crescent below Jupiter. By
July 2, Venus had risen to within four degrees below Jupiter
and the crescent had grown thicker, while the apparent disk
size was a bit smaller. Jupiter was still displaying the rather
odd belt pattern that I observed a few days earlier. Hopefully l
will get a chance to get a clearer view of the new pattern of
Jupiter's cloud belts as Jupiter rises earlier and higher into a
dark, steady visible sky. As for Venus, of course, it will just
display a thicker and thicker crescent, then dichotomy (half
phase), then a gibbous phase on a gradually shrinking apparent disk size, and then a nearly full phase as it then sinks again
into the morning twilight in winter. I will have long joined the
departed AAA members by December 2117, the time when
Venus will once again appear as a black drop of India ink
against the bright disk of the Sun. ■
NEXT MONTH IN EYEPIECE
Our Look Ahead to September: Amy Wagner’s new
journey: “Why We Explore;” Stan Honda continues his amazing “Focus on the Universe” series; Richard Brounstein makes
us think in “What If;” Ed Fox reviews “The 4% Universe;”
Dan Harrison reports on dark skies from Sark in the English
Channel Islands; “Kleegor’s Universe” explores the funny
side of astronomy; Ed Fox’s AAA Briefs in Astronomy continue to inform us; Rich Rosenberg’s “What’s Up in the Sky”
points our scopes in the right direction, plus Nebula of the
Month, Astronomical Fact of the Month….and more!!!
AAA ONLINE STORE IS NOW OPEN
AAA Presents: A new and exciting wide selection of
logo merchandise
for our members to
purchase online
“Shop the Stars”
www.aaa.org/store
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