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SUPARCO
ASTRONOMY &
ASTROPHYSICS
Newsletter
Volume 04, Issue 03
March 2015
PAKISTAN SPACE & UPPER ATMOSPHERE
RESEARCH COMMISSION
2015
contents
BULLETIN
Volume-04, March 2015
Pakistan’s Space Vision 2040, was
approved by the Prime Minister of
Pakistan which inter-alia included
augmentation / strengthening of
the Astronomy and Astrophysics
program of SUPARCO. SUPARCO`s
astronomy and astrophysics program
is mainly focused on theoretical and
observational research, for which an
astronomical observatory is planned
to be established. Research studies
pertaining to deep space objects
including galaxies, nebulae and
variable stars are also being initiated.
Search for earth-like planets is a hot
topic in astrophysics nowadays. It is
planned to conduct research studies
in this field also.
1)Meteors
Pg : 01
2)
Events of the Month
Pg : 07
3)
Monthly Star Guide
Pg : 05
4)
Monthly Science News
Pg : 12
5)
Software Review
Pg : 15
6)
Magnetic Stroms Monitored by SUPARCO
Pg : 17
7)
Participation in International School for Young Astronomers (ISYA) 2014
Pg : 21
METEORS
Meteors are cometary debris. They are small and
friable usually no more than of centimeter size and
so never reach the Earth’s surface intact. There are
many well-defined showers, associated with comets
which can often be identified; other meteors are
sporadic, not associated with any known comet, and
so may appear from any direction at any moment.
Meteors can, of course, occur in daylight, as was
pointed out by the Roman philosopher Seneca
about 20 AD, and may be tracked by radio and radar.
Meteors are not associated with meteorites, which
come from the asteroid belt. The link with comets
was first proposed in 1861 by D. Kirkwood; he
believed that meteors were the remnants of comets
which have disintegrated – and in some cases this is
true enough. In 1862 G. V. Schiaparelli demonstrated
the link between the Perseid meteor shower and the
periodical comet Swift Tuttle, and other associations
were soon established.
Some well-known periodical comets are the parents
of meteor showers. Halley’s Comet produces two,
the η Aquarids of April and the Orionids of October;
Comet P/Giacobini–Zinner can occasionally yield rich
displays, as in 1933. Biela’s Comet, which broke up
and was last seen in 1852, produced ‘meteor storms’
in 1872 and in 1885; in recent years this shower (the
Andromedids) has been almost undetectable, but it
has been calculated that it may return around 2120,
when the orbit of the stream will be suitably placed.
The Lyrids, first recorded in 687, are linked with
Thatcher’s Comet of 1862, which has a period of over
400 years. The rich Geminid shower of December has
an orbit very like that of asteroid 3100 Phæthon, and
it is widely believed that Phæthon may be the parent
of the stream, adding credibility to the suggestion
that some near-Earth asteroids may be extinct
comets.
EARLY THEORIES
Meteors were once regarded as atmospheric
phenomena. Aristotle believed them to be due to
vapours from Earth created by the warmth of the
Sun; when they rose to great altitudes they caught
fire, either by friction or because the column of
air around them cooled, so squeezing out the hot
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vapours rather as toothpaste can be squeezed out
of a tube. Even Newton believed that meteors were
volatile gases which, when mixed with others, ignited
to cause ‘Lightning and Thunder and fiery Meteors’.
NATURE OFMETEORS
The status of meteors was solved in 1798 by two
German students, H. W. Brandes and J. F. Benzenberg,
of the University of Gottingen. Between 11 September
and 4 November they observed meteors from sites
15.2 km apart, giving them a useful ‘baseline’, and
made 402 measurements; in 22 cases they found
that the same meteor had been seen from each
site, and its track plotted. This made it possible to
determine the height of the meteor by the method
of triangulation. The heights at which the meteors
disappeared ranged between 15 km and 226 km; the
mean burnout altitude was found to be 89 km now
known to be very near the truth. The total number
of meteors entering the atmosphere daily has been
given as 75,000,000 for meteors of magnitude 5 or
brighter. An observer under ideal conditions would
expect to see between about 5 and 15 naked-eye
meteors per hour (except during a shower, when the
number would be higher). Meteors of magnitude −5
or brighter – that is to say, appreciably more brilliant
than Venus – are conventionally termed fireballs. Very
occasional fireballs, such as those of 20 November
1758 and 18 August 1783, may far outshine the Moon.
A meteor may enter the atmosphere at a velocity
anywhere between 11 km s−1 and 72 km s−1; it will
be violently heated as it enters the upper atmosphere
at an altitude of 150 km above the ground. It is
vaporized; atoms from its outer surface are ablated
and collide with molecules in the atmosphere,
exciting and ionizing them, producing a trail which
may extend for many kilometers. There is little
deceleration before the meteor is destroyed. What we
see is, therefore, not the particle itself, but the effects
which it produces in the atmosphere during the final
moments of its existence.
Particles below about 0.1 mm in diameter are termed
micrometeorites, and do not produce luminous
effects. Some are cometary, while others must
be classed as Zodiacal ‘dust’. Meteors are easy to
photograph – the earliest really good picture, of an
Andromedid, was taken by L. Weinek, from Prague, as
long ago as 27 November 1885 – but meteor spectra
are much more difficult, because one never knows
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just when or where a meteor will appear. Many
spectra have been obtained (largely by amateurs)
and it seems that meteors are made up of material
of the type only to be expected in view of their
cometary origin.
Radar studies of meteor trails are now of great
importance; the first systematic work was carried
out in 1945 by J. S. Hey and his team, with the δ
Aquarids. However, amateur observations are still
very useful indeed.
METEOR RADIANTS
Because the meteors in any particular shower are
moving through space in parallel paths (or virtually
so), they seem to come from one set point in the sky,
known as the radiant. The shower is named after the
constellation in which the radiant lies. One exception
refers to the January meteors, the Quadrantids; they
are named after Quadrans Muralis, a constellation
added to the sky in Bode’s maps of 1775 but later
rejected – its stars are now included in Bootes, but
the old name has been retained.
A list of the principal annual showers is given in
Table 15.1. A selected list of minor showers is
given in Table 15.2, although the low hourly rate of
these showers means that the data are decidedly
uncertain.
The ZHR, or Zenithal Hourly Rate, is given by the
number of naked-eye meteors which would be
expected to be seen by an observer under ideal
conditions, with the radiant at the zenith. In practice
these conditions are never met, so that the observed
hourly rate is bound to be rather lower than the
theoretical ZHR.
METEOR SHOWERS
Material may leave a comet either in front of or
behind the nucleus. Dust particles ejected from
the nucleus may return to perihelion earlier than
the comet itself, or may return later; gradually the
material is distributed all around the comet’s orbit,
forming a loop. With older showers, such as the
Perseids, this has had sufficient time to happen; with
younger showers it has not, so that good displays
are seen only when the Earth passes through the
thickest part of the swarm. We must also consider
what is termed the Poynting–Robertson effect. In
reradiating energy received from the Sun, a particle
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will lose orbital velocity and will spiral inward towards
the Sun; therefore old streams are depleted in small
particles (although even smaller particles are ejected
altogether, by radiation pressure).
The Perseid shower of early August is consistent, and
any observer who looks up into a dark, clear sky at
any time during the first part of the month will be
very unlucky not to see a few Perseids. The October
Draconids, associated with Comet P/Giacobini–Zinner,
are usually sparse, but produced a major storm in
1933, when for a while the ZHR reached an estimated
6000; a weaker but still rich storm occurred in 1946
(this was the first occasion on which meteors were
systematically tracked by radar). Nothing comparable
from the Draconids has been seen since. It must
be remembered that meteor streams are easily
perturbed by planets, and no two orbits are exactly
alike.
The Leonids can produce the most spectacular storms
of all; a selected list is given in Table 15.3 (drawn from
the researches carried out by John Mason). In 1833
and 1866 it was said that meteors ‘rained down like
snowflakes’. No major displays were seen in 1899 and
1933, because the main swarm did not intersect the
Earth’s orbit at the critical time, but there was another
storm in 1966 – unfortunately not seen from Europe,
because it occurred during European daylight, but
spectacular from parts of North America, such as
Arizona.
Comet Tempel-Tuttle returned to perihelion in 1998,
and was expected to produce another meteor storm.
The predicted date was 17 November, 258 days after
the comet had passed through perihelion, but in
fact the richest display was seen on 16 November –
not a ‘storm’, but certainly striking. It was calculated
that the dust stream left behind by the comet does
not have uniform cylindrical structure, but consists
of a number of discrete, separate arcs of dust, each
released at a different return of the comet. If the
Earth passes through a thin filament, the meteor
shower is brief but intense. If it passes through a
broader filament, the shower is less intense, but lasts
longer. If the Earth passes through a gap between
filaments, the display is weak. If it passes through a
broad filament first, and then through the edge of a
narrower filament, there will be two peaks of activity.
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The great storm of 1833 was
caused by a dust trail generated
in 1800, 33 years earlier; the 1966
storm was due to dust released
from the comet in 1899. The
displays of 1998 and 1999 were
due to an arc-shaped cloud
of dust shed by the comet in
1366. In 1999 there was indeed
a meteor storm, peaking at 02
hours GMT on 18 November; if
not as splendid as the storms
of 1833 and 1866, it was very
spectacular, with a peak ZHR of
well over 2000. It was of brief
duration, but was well seen from
cloud-free areas of Europe. From
Oban (Scotland) Iain Nicolson
found the peak activity to be
from 0200 to 0215GNT, and had
declined markedly by 0240. Many
of the meteors were very bright,
with long, sometimes persistent
trains.
During the shower, there were
two telescopic reports of flashes
on the surface of the Moon,
and it was suggested that these
might be due to impacting
Leonids, but this seems most
improbable; a meteor could not
produce a visible lunar flash – a
meteorite-sized object would be
needed, and meteorites are not
associated with comets or with
meteor showers.
Danger from Meteors
From ground level, meteors –
unlike meteorites – are quite
harmless. It was suggested that
the expected 1998–9 Leonid
shower might affect space-craft,
such as the Hubble Telescope,
but no damage was reported,
and all in all it seems that the
danger from meteors is not very
great.
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Events of the month
March 5 - Full Moon
The Moon will be directly opposite the Earth from the Sun and will be fully illuminated as seen
from Earth. This phase occurs at 18:05 UTC.
March 20 - New Moon
The Moon will be directly between the Earth and the Sun and will not be visible from Earth. This
phase occurs at 09:36 UTC. This is the best time of the month to observe faint objects such as
galaxies and star clusters because there is no moonlight to interfere.
Page no. 07
March 20 - Total Solar Eclipse
A total solar eclipse occurs when the moon completely blocks the Sun, revealing the Sun’s
beautiful outer atmosphere known as the corona. The path of totality will begin in the central
Atlantic Ocean and move north across Greenland and into northern Siberia. This eclipse will not
be visible from any place in Pakistan.
March 20 - March Equinox
The March equinox occurs at 22:45 UTC. The Sun will shine directly on the equator and there
will be nearly equal amounts of day and night throughout the world. This is also the first day of
spring (vernal equinox) in the Northern Hemisphere and the first day of fall (autumnal equinox)
in the Southern Hemisphere.
Page no. 08
Monthly Star Guide (MARCH)
Day and night are nearly equal in length all over the
world as the equinox approaches, around March 21, the
start of northern spring and southern fall. Orion and the
bright stars around it are in the west, while from southern
latitudes rich fields of stars, from Carina to Centaurs, lie
south and southeast.
Northern Latitudes:
Looking North
The Big Dipper (Plough) stands high in the northeast. Its
bowl opens downward, toward Polaris, while its handle
points east to Arcturus, who’s rising signals the arrival of
spring. Capella is the most prominent star in the North
West, with Perseus and Cassiopeia now sinking low toward
the western horizon.
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Looking South
Leo, shaped like a
crouching lion, lies due
south, with the fainter
stars of Cancer to its right.
Virgo, with its brightest
star Spica, is rising in the
southeast, while Orion and
the other stars of winter
depart in the southwest.
Sirius appears to twinkle
above the southern
horizon.
Page no. 10
monthly science news
Astronomers identify gas
spirals as a nursery of twin
stars through ALMA
Astronomers have found spiral arms of molecular
gas and dust around the “baby twin” stars, binary
protesters. Gas motions to supply materials to the
twin were also identified. These observational results
unveil, for the first time, the mechanism of the birth
and growth of binary stars, which are ubiquitous
throughout the universe.
Researchers detect
possible signal from
dark matter
Scientists have picked up an atypical photon
emission in X-rays coming from space, and
say it could be evidence for the existence
of a particle of dark matter. If confirmed,
it could open up new perspectives in
cosmology.
Saturn’s largest moon
is a windy place: Titan
dune puzzle solved
Titan, Saturn’s largest moon, is a peculiar
place. Unlike any other moon, it has a
dense atmosphere. It has rivers and lakes
made up of components of natural gas,
such as ethane and methane. It also has
windswept dunes that are hundreds of
yards high, more than a mile wide and
hundreds of miles long -- despite data
suggesting the body to have only light
breezes. Winds on Titan must blow faster
than previously thought to move sand. The
discovery may explain how the dunes were
formed.
Page no. 11
Warm gas pours ‘cold
water’ on galaxy’s starmaking
Some like it hot, but for creating new stars, a
cool cosmic environment is ideal. As a new study
suggests, a surge of warm gas into a nearby galaxy
-- left over from the devouring of a separate galaxy
-- has extinguished star formation by agitating the
available chilled gas.
Successful launch
of NASA’s Orion
spacecraft heralds
first step on journey
to Mars
NASA marked a critical step on the
journey to Mars with its Orion spacecraft
during a roaring liftoff into the dawn sky
over eastern Florida on Friday, Dec. 5,
2014, aboard a Delta IV Heavy rocket.
Interstellar
mystery solved by
supercomputer
simulations
An interstellar mystery of why stars form
has been solved thanks to the most realistic
supercomputer simulations of galaxies yet
made. Theoretical astrophysicists found that
stellar activity -- like supernova explosions
or even just starlight -- plays a big part in
the formation of other stars and the growth
of galaxies.
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The hot blue stars
of messier 47
Messier 47 is located approximately
1600 light-years from Earth, in the
constellation of Puppis (the poop deck
of the mythological ship Argo). It was
first noticed some time before 1654 by
Italian astronomer Giovanni Battista
Hodierna and was later independently
discovered by Charles Messier himself,
who apparently had no knowledge of
Hodierna’s earlier observation. Although
it is bright and easy to see, Messier 47 is
one of the least densely populated open
clusters. Only around 50 stars are visible
in a region about 12 light-years across,
compared to other similar objects which
can contain thousands of stars.
Kepler proves
it can still find
planets
To paraphrase Mark Twain, the
report of the Kepler spacecraft’s
death was greatly exaggerated.
Despite a malfunction that ended
its primary mission in May 2013,
Kepler is still alive and working.
The evidence comes from the
discovery of a new super-Earth
using data collected during
Kepler’s ‘second life.’
Ref: http://www.sciencedaily.com/
Page no. 13
Supermassive black hole
blows molecular gas out
of a galaxy at one million
kilometers per hour
New research has solved a long-standing mystery
surrounding the evolution of galaxies, deepening
our understanding of the future of the Milky Way.
The supermassive black holes in the cores of some
galaxies drive massive outflows of molecular
hydrogen gas. As a result, most of the cold gas is expelled from the galaxies. Since cold gas is
required to form new stars, this directly affects the galaxies’ evolution.
High Energy
Stereoscopic
System detects
its first pulsar
The High Energy Stereoscopic
System telescope in Namibia
has detected gamma rays of
only 30 Giga electron volts
(GeV) from the Vela pulsar. This
is the first pulsar to be detected
by HESS and the second - after
Crab in 2011- to be spotted
by ground-based gamma ray
telescopes.
Controversial clues of two
‘Goldilocks planets’ that
might support life are proven
false
Mysteries about controversial signals from a star
considered a prime target in the search for extraterrestrial
life now have been solved. The research proves, for the
first time, that some of the signals actually are from events
inside the star itself, not from the two so-called ‘Goldilocks
planets,’ which were suspected to be just-right for life
and orbiting the star at a distance where liquid water
potentially could exist. No planets there just star burps.
Page no. 14
Software
Review
Redshift 7 Premium
Redshift 7 is your standard astronomy
software package done brilliantly, with
several impressive extras that are sure to
thrill. Their guided tours of our galaxy, outer
galaxies and dozens of other interactive
tours (that are updated as new discoveries
in the astronomy field are announced) is an
excellent way to know the latest on the skies
above. One of their more unique tours, the
Disappearance of the Jovian Moons, which
follows the eclipse of the moons of Jupiter,
is just one of the fascinating tours you can
take.
Redshift 7 astronomy software also has a
powerful telescope control for those wishing
to integrate the live sky into their astronomy
experience. Most popular brands of robotic
telescopes are compatible with their
telescope function. Focus your telescope on
a star cluster you’d like to learn more about,
and Redshift 7 will become your personal
star expert. Redshift 7 is ASCOM and EQ6
compliant.
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MAGNETIC STORMS
MONITORED BY
SUPARCO
The Space Weather Monitoring Facilities at SUPARCO recorded a significant (G3) geomagnetic
storm caused by the arrival of the Coronal Mass Ejection (CME). This event was the strongest
since The same happened and a CME was ejected on June 5, 2014 which reached Earth by June
7 recorded in the Magnetograms obtained from Islamabad Observatory at the time of impact,
1630 UT. Its associated geomagnetic disturbance, which caused about a variation of 175 nano
Tesla, continued through the next few days.
Figure 1: Magnetograms from the Islamabad Geomagnetic Observatory show the impact of
geomagnetic storm due to a solar filament eruption
Page no. 17
The geomagnetic storm had a very mild start
but by June 8, it had turned into a G2 category
geomagnetic storm on a NOAA Scale. To see
more information on NOAA Space Weather
Scales, please follow the link: http://www.swpc.
noaa.gov/NOAAscales/
Figure 2: The 4 day graph depicts the Kp Index taken from the Space Weather Prediction
Centre (SWPC) at the National Oceanic and Atmospheric Administration (NOAA). The Kp
index shows levels reaching 6 on June 8 and the disturbed conditions persisting for 12
hours indicated by red bars.
Page no. 18
The Atmospheric Imaging Assembly (AIA)
instrument (at a wavelength of 30.4 nm) on
board the Solar Dynamics Observatory (SDO)
captured the magnetic filament responsible
for causing the geomagnetic storm. As seen
by the images below, the magnetic filament is
seen to be floating in the chromosphere on the
left and is seen lifting off on the right.
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Participation in International
School for Young Astronomers
(ISYA) 2014
Introduction
The International School for Young Astronomers is a project of the International
Astronomical Union (IAU), established in 1967. The objective of the ISYA is to broaden
the participants’ perspective on astronomy by lectures from an international faculty
on selected topics of astronomy, seminars, practical exercises and observations, and
exchange of experiences.
It is a three-week international postgraduate school for regions where students & young
researchers have less opportunity to be directly exposed to the full extent of up-to-date
astrophysics (mainly, but not exclusively, from astronomically developing countries).
During the school both theory and observations are addressed. The participants are
essentially coming from countries in the region of the country hosting the ISYA. The
lecturers are experts coming from all over the world.
IAU provides financial support for all travel of students, young researchers and faculty,
both within the host country and international. The host institution must obtain the
funds to cover expenses during the ISYA, such as room and boarding for students and
faculty, and provides the infrastructure for lectures and tutorials. For countries with a
national astronomy program, part of the school could take place at an observatory site
for training in observational techniques and if possible in data reduction. However, if
this is hard to organize, then observational training with data reduction can be provided
through the use of remote robotic telescopes.
An official from SUPARCO participated in 36th International School for Young
Astronomers (ISYA) 24th November – 12th December 2014, Chiang Mai, Thailand.
Objectives and Organization of ISYA
An ISYA is always oriented towards developing countries and takes place in these
countries. Nevertheless, an ISYA takes place in countries and universities with a
reasonably long-term interest in astronomy to sustain further development. During an
ISYA there is no donation of research equipment, such as telescopes, for example.
The main goals are:
• to broaden the point of view of the students – a young astronomer should not only stick
to a single, very specialized, branch of astronomical research;
• to fight against the isolation of the “lonely astronomer”;
• to initiate collaboration on a larger geographical scale.
An ISYA is organized through an agreement signed between the IAU and a host Uni
versity, and this is often linked to a development project, such as the establishment of a
new astronomy department, the installation of a new telescope, etc.
Page no. 21
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Key Topics Covered in ISYA 2014
The Sun and Solar System; Stellar physics and Evolution; Exoplanets; Variable Stars; Stellar
Pulsation and Asteroseismology; Binary Stars; Stellar Clusters; Galaxies and Cosmology;
Black Holes; Telescopes and Instrumentation; High Time Resolution Astronomy; Space
Astronomy; Radio Astronomy.
Remarks
Today the lonely astronomer is also the one who is not associated with an international
project. The development of the concept of the virtual observatory (VO) will induce,
even more, the decentralization of research and will allow individuals to develop their
expertise and competence in the international research arena. The objective of the
ISYA is to introduce more young researchers into the international domain, but without
cutting them from off their roots by, among other, offering them the possibility to start
their network of scientific contacts in the context of their own national environments.
In ISYA 2014 students & young researchers learned spectroscopic data and analysis;
photometric data and analysis; observation with the 2.4-m Thai National Telescope
and the 50-cm Chiang Mai University telescope; the PROMPT robotic telescopes; using
surveys and data archives; and planetary observing.
To become a scientist is not an easy task and to participate in an ISYA is one way to
contribute to this goal. It allows students & young researchers to become more confident
to discuss their ideas with others, outline research projects, and build international
relationships.
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R
OSPHERE RE
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AR
AN
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March
- 201
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NVeoluwmse-4l , Issue5 3
CO M M I S S I O
S PA C E & U P
CH
PE
M
AT
Contact Information
SPAS Directorate
Gulzar-e-Hijri SUPARCO Road
Sector 28, SUPARCO, Karachi, Pakistan
Tel: 021-34690765-74
Fax 021-34690795
Email: [email protected]
SUPARCO - ASTRONOMY &
ASTROPHYSICS Bulletin is a
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