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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 Page no. 01 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 Page no. 02 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 Page no. 03 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. Page no. 04 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. Page no. 05 Page no. 06 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. Page no. 09 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. Page no. 12 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. Page no. 15 Page no. 16 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. Page no. no. 19 13 Page Page no. no. 20 14 Page 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 Page no. 22 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. Page no. 23 Page no. 24 Page no. 25 Page no. 26 R OSPHERE RE SE AR AN ST March - 201 N etter 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 monthly publication PA K I