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Kitt Peak Nightly Observing Program
Splendors of the Universe on YOUR Night!
Many pictures are links to larger versions.
Click here for the “Best images of the AOP” Gallery and more information.
Rigel, also known by its Bayer designation Beta
Orionis (β Ori, β Orionis), is the brightest star in
the constellation Orion and the seventh brightest
star in the night sky, with visual magnitude 0.13.
The star as seen from Earth is actually a triple star
system, with the primary star (Rigel A) a bluewhite supergiant of absolute magnitude −7.84 and
around 120,000 times as luminous as the Sun.
NGC 457 (also known as the Owl Cluster, the ET
Cluster, or Caldwell 13) is an open star cluster in
the constellation Cassiopeia. It was discovered by
William Herschel in 1787, and lies over 7,900 light
years away from the Sun. It has an estimated age
of 21 million years.
M45: The Pleiades Star Cluster. A bright, nearby
star cluster in the last stages of star formation. It
has six to seven bright stars along with hundreds of
fainter stars. It lies about 380 lightyears away and
is around 100 million years old.
M42: The Great Orion Nebula. This is a region of
star formation about 1,500 ly away. It is 30 ly
across and contains enough material to make
10,000 stars the size of our sun.
M31: The Andromeda Galaxy, our nearest major
galactic neighbor. It is a spiral galaxy, lies
2,200,000 lightyears away and has a diameter of
180,000 lightyears. This galaxy contains as much
material as 300 billion suns.
M32: A small but bright companion galaxy to
M31. It orbits M31 much like the Moon orbits the
Earth. It lies at the same distance as M31 but is
much smaller (8,000 lightyears across).
M110: The last Messier object, and the more
distant of the Andromeda Galaxy's two
companions. M110 is a tiny elliptical galaxy, about
7,000 lightyears across, containing a billion suns.
Mercury, the closest planet to the Sun, always
appears near the Sun in the sky and is only visible
shortly after sunset or before sunrise. It zips around
the Sun every 88 days and is named for the speedy
Roman messenger god.
Venus, the second planet, is the brightest natural
object in the sky other than the Sun and Moon and
is often erroneously called the “morning star” or
“evening star.” It is completely wrapped in sulfuric
acid clouds and its surface is hot enough to melt
lead.
Mars, the red planet, has a thin carbon dioxide
atmosphere, clouds, dust storms, and polar caps
made of dry ice. Images of dry riverbeds from
orbiting spacecraft show us that liquid water once
flowed on the Martian surface.
Jupiter is the largest planet in the Solar System, a
“gas giant” 11 Earth-diameters across. Its
atmosphere contains the Great Red Spot, a longlived storm larger than Earth. The 4 large Galilean
satellites and at least 59 smaller moons orbit
Jupiter.
Neptune, eighth planet from the Sun, is a blue
“gas giant” about 4 Earth-diameters across. At
least 13 moons orbit Neptune. Galileo accidentally
observed Neptune in 1612 and 1613 but did not
realize it differed from the stars—its true discovery
would wait until 1846.
Comets were once harbingers of doom—
unpredictable and terrifying celestial sights. We
now know that comets are balls of ice, rock, and
dust tens of kilometers across. As comets approach
the Sun, the ices vaporize and sometimes form
long, spectacular tails.
Clouds: Darn! These pesky intruders have annoyed
astronomers for millenia. Kitt Peak usually has
clear skies; call us at (520) 318-8726 and join us
again some time.
The Green Flash: A smidge of green on the top of
the sun as it sets (or rises). This rare event needs
just the right atmospheric conditions.
Milky Way: That clumpy band of light is evidence
that we live in a disk-shaped galaxy. Its pale glow
is light from billions of suns!
Quick streaks of light in the sky called meteors,
shooting stars, or falling stars are not stars at all:
they are small bits of rock or iron that heat up,
glow, and vaporize upon entering the Earth's
atmosphere. When the Earth encounters a clump of
many of these particles, we see ameteor
shower lasting hours or days.
Satellites: Human technology! There are almost
10,000 of these in Low Earth Orbit (we can't see
the higher ones). We see these little "moving stars"
because they reflect sunlight.
Scintillation: The twinkling of star light is a
beautiful effect of the Earth's atmosphere. As light
passes through our atmosphere, its path is deviated
(refracted) multiple times before reaching the
ground. Stars that are near to the horizon will
scintillate much more than stars high overhead
since you are looking through more air (often the
refracted light will display individual colors). In
space stars would not twinkle at all- and this is the
way astronomers would like it if they could control
the effects of this troubling twinkle.
Your Telescope Operator and Guide. Thank
you for joining me this evening! See you
soon!!
The web page for the program in which you just participated
ishttp://www.noao.edu/outreach/nop. Most of the above images were
taken as part of the all-night observing program. For more information on this
unique experience please visit http://www.noao.edu/outreach/aop.
Copyright © 2008 Kitt Peak Visitor Center