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SUPARCO - ASTRONOMY & ASTROPHYSICS BULLETIN Volume I, Issue 3 Pakistan Space Vision 2040, was approved by the Prime Minister of Pakistan which inter-alia included augmentation / strengthening of the Astronomy and Astrophysics programmes of SUPARCO. SUPARCO`s astronomy and astrophysics program is mainly focused on theoretical and observation research. For this 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. Inside this Issue: March, 2012 Cycles of the Sun, Earth and Planets Our Sun, the nearest star, rises and sets every day. This motion of the Sun in the sky occurs because of the rotation of the Earth on its axis. The Earth completes one rotation in 24 hours and takes approximately 365.25 days to complete one revolution around the Sun, which is called a year. Rotation is the turning of a body on its axis, whereas a revolution means the motion around a point outside the body. Our sky is always filled with stars even in daytime. It is glare of the Sun which makes them invisible during daytime. If it would be possible to see stars in daytime, then the daily observation of the Sun would allow us to see that the Sun appears to drift in the sky against the background of stars. Factually this slow drifting of the Sun in the sky is due to the Earth’s motion in its orbit. The Earth moves at an average speed of 30 km/s in its orbit and at a distance of around 149.6 million km from the Sun. Due to this daily drifting, the Sun appears to move over a path, known as Ecliptic. In other words ecliptic is the projection of the Earth’s orbit in the sky. Furthermore, it appears that the sun completes one revolution per year by moving in front of different constellations, named as Zodiac Constellations. This apparent motion of the Sun has an important effect as it creates seasons on the Earth. Cycles of the Sun, Earth and Planets Software Review Sky this Month & Events Sun Spots Ec Ecliptic Book Review lip tic Web Review Magentic Stroms Monitored by SUPARCO Venus, Our Sister Planet Events of Month Date Time Event\Direction 03 Mar After Sunset Mars in opposition \ East 05 Mar 7:30 Murcury conjuct Uranus \ West 14 Mar After Sunset Conjuction of Venus & Jupiter \ West 26 Mar After Sunset Moon, Jupiter & Venus together with new moon Seasons arise because of the simple fact that the Earth is tilted on its axis and this tilt is about 23.5 degrees. Both the axial tilt and the Earth’s motion around the Sun create seasons on the Earth. There is a misconception that seasons arise as the Earth move near and far from the Sun and in its orbit. However seasons occur because the Earth receives different amount of light during different times of the year. For example during summer season, position of the Earth and the Sun is such that the sun rays fall vertically on the Earth so that per unit area on the Earth receives more light which increases the surface temperature. SUPARCO - ASTRONOMY & ASTROPHYSICS Bulletin is a monthly publication Page II Cycles of the Sun, Earth and Planets There is another interesting fact that is when there is summer in Northern hemisphere there is winter in Southern hemisphere and vice versa. On the day of the summer solstice (longest day) in late June, Earth’s Northern hemisphere is inclined toward the Sun (Fig 1) and sunlight shines almost straight down at Northern latitudes. At Southern latitudes, sunlight strikes the ground at an angle and spreads out. Similarly on the day of the winter solstice (shortest day) in late December, Earth’s Northern hemisphere is inclined away from the sun, and sunlight strikes the ground at an angle and spreads out (Fig 2). At Southern latitudes, sunlight shines almost straight down and does not spread out, hence the situation reverses. Fig 1 Fig 2 The planets of our solar system produce no visible light of their own; they are visible only by the reflected sunlight. Mercury, Venus, Mars, Jupiter, and Saturn are all easily visible to the naked eye and look like stars. If the solar system is seen from North celestial pole, it would seem that the planets are moving in the same counterclockwise direction in their orbits, with the planets farthest from the sun moving the slowest. Planets are always seen near the ecliptic in the sky because their orbits lie in nearly the same plane. The planet, whose orbits SUPARCO - ASTRONOMY & ASTROPHYSICS Bulletin is a monthly publication lie outside the orbit of Earth, move slowly eastward along the ecliptic. Mars moves completely around the ecliptic in slightly less than 2 years, but Saturn, being farther from the Sun, takes nearly 30 years. Mercury and Venus also stay near the ecliptic, but they move differently from the other planets because they have their orbit inside the orbit of Earth. This means they never move far from the Sun in the sky. As seen from Earth, they move eastward away from the Sun and then back toward the Sun, when they are at their closest approach to the Sun. . . To find one of these planets, look above the western horizon after sunset or above the eastern horizon before sunrise. Venus is easier to locate because it is brighter and also its larger orbit carries it higher above the horizon than Mercury. Page III Software Review WorldWide Telescope Developed by Microsoft, WorldWide Telescope (WWT) is virtual astronomy software which displays the astronomical sky as maps. Users are able to pan around outer space and zoom as far into any one area as the data will allow. It is possible to view the sky in many wavelengths of light. The software utilizes Microsoft's Visual Experience Engine technologies to function. The program is designed to scale from web browser to desktop, to large multi-channel full dome digital planetarium. The WWT project began in 2002 at Microsoft Research and Johns Hopkins University and it was announced at the TED Conference in Monterey, California in February 2008. WorldWide Telescope has five main modes. These are Sky, Earth, Planets, Panoramas, and Solar System. Sky mode is the main feature of the software. It allows users to view high quality images of outer space, with images from various space and earth-based telescopes. Each image is shown at its actual position in the sky. There are over 200 full-sky images in spectral bands ranging from radio to gamma. Earth mode allows users to view a 3D model of the Earth, similar to NASA World Wind, Microsoft Virtual Earth and Google Earth. SUPARCO - ASTRONOMY & ASTROPHYSICS Bulletin is a monthly publication Planets mode currently allows users to view 3D models of eight celestial bodies: Venus, Mars, Jupiter, four of Jupiter's larger moons, and our own planet's Moon. The Panorama mode allows users to view several Mars Rover panoramas. Solar system mode displays the major solar system objects from the Sun to Pluto, and Jupiter's moons, orbits of all solar system moons, all 550,000+ minor planets positioned with their correct scale, position and phase. The user can move forward and backward in time at various rates, or type in a time and date for which to view the positions of the planets, and can select viewing location. The program can show the Solar System the way it would look from any location at any time between 1AD and 4000AD. Using this tool a user can watch eclipse, occultation, or astronomical alignment, and preview where the best spot might be to observe a future event. In this mode it is possible to zoom away from the Solar System, through the Milky Way, and out into the cosmos to see a hypothetical view of the entire known universe. Other bodies, spacecraft and orbital reference frames can be added and visualized in the Solar System Mode using the layer manager. This software has received awards like AIGA Annual Design Competition for the experience design category and I.D. Magazine 2009 Annual Design Review for interactive category. Page IV Web Review http://www.starchild.gsfc.nasa.gov The website under review for the month of March is www.starchild.gsfc.nasa.gov. This website is a service of High Energy Astrophysics Science Archive Research Center (HEASARC), within the Astrophysics Science Division (ASD) at NASA / GSFC. As its name depict, this website is solely designed keeping in mind of kid’s level astronomy. The website starts with a page welcoming young astronomers. This website has been developed primarily by a duo of middle school teachers who generously volunteered their time and talents for making this website. StarChild has two sections namely level 1 and level 2 for astronomy material. Information on each section is primarily devoted to the students of different grade levels. The pattern of information is same but additional information is given in the level two of the website. Each page then goes on further with other useful links to the related information. For school teachers there is a link given on the main page describing the usage with instructions and guidance for the material available on the website. This website is very useful resource for teachers teaching astronomy at primary level. SUPARCO - ASTRONOMY & ASTROPHYSICS Bulletin is a monthly publication Book Review The Photographic Atlas of the Moon published by Cambridge University press is a day-by-day photographic guide to observe the features of the Moon through a small telescope. This book is compiled by three amateur astronomers S.M. Chong, Albert Lim and P.S. Ang. All the pictures in the book are taken by using 40 cm telescope and a high resolution low speed film. Whole Moon images are provided for each day of 29-day lunar cycle, with labeled features and accompanying descriptive text. Selected lunar features are shown at high magnification to highlight and illustrate certain regions. All lunar features are labeled using current IAU terminologies. A comprehensive set of appendices provide the details about the phases of the Moon and index of all lunar features named in the text. This book is an invaluable guide book for those who are interested in lunar observation with small telescope. Starting with the conjunction, the book goes on explaining daily increment in moonshine at lunar surface with details of features thus visible at that time. Each day photograph is also shown with the details of instruments used to take the photograph. Photographic atlas of the Moon can be used as a quick reference guide for daily moon appearance in the sky. Having this book with the small telescope or binocular one can explore the detailed features of the Moon. Page V Sky this Month March 3, 2012 – Mars in opposition Mars will be closest to Earth and its surface will be fully illuminated by the Sun. This view will be visible in the eastern direction after sunset. This is the best time to view and photograph Mars. March 5, 2012 - Mercury conjunct Uranus Mercury and Uranus will be in conjunction with each other in the sky, in western direction. March 20, 2012 - Equinox of March March Equinox occurs at 05:14 UT. The Sun will shine directly on the equator and the days and nights will be almost equal in the whole world. This is also the first day of spring (spring equinox) in the northern hemisphere and the first day of fall (autumnal equinox), in the southern hemisphere. March 22, 2012 - New Moon Moon will be directly between Earth and Sun and will not be visible from Earth. This phase takes place at 14:37 UT. Chances of new moon will be next day. March 26, 2012 - Moon, Jupiter and Venus together with New moon New moon will be between the two brightest planets, Venus and Jupiter. It’s a nice time to see the top three brightest object of the night sky together in the same section of the sky. Although the sequence of the objects will be Jupiter, the third brightest; Moon, the brightest and then Venus, the second brightest object as seen from the horizon. This view will be visible in the west direction after sunset. March 8, 2012 - Full Moon Earth will be between the Sun and Moon, and therefore, the Moon will be fully illuminated as seen from Earth. March 14, 2012 - Conjunction of Venus and Jupiter The two bright planets will appear 3 degrees apart from each other in the sky in the west direction. SUPARCO - ASTRONOMY & ASTROPHYSICS Bulletin is a monthly publication Page VI Sunspots Sun which is the most common object we see in day has dark spots on it known as sunspots. These spots could easily be seen through any small telescope but during a foggy day it is a great opportunity to view bigger ones. Sunspots have always been mysterious for human beings and without these spots on it; Sun would rather be a boring star! The human observation of sunspots is very old and their written record exists since Greek times. Sunspots occur in groups as well as individuals, and their number varies from minimum value to maximum following an 11 year cycle known as sunspot cycle. When sunspots are very small in number it is called Solar Minimum, and when they reach to their maximum numbers it is called Solar Maximum. Although sunspots appear dark but still have temperature about 3800 Kelvin as these are relatively cooler regions of solar surface and the average surface temperature of the sun is about 6000 K. Image of the sunspot taken by SUPARCO on Feb 23, 2012 Since we can only view one side of the Sun therefore to calculate sunspots over the whole surface of the Sun is to be observed for one month because it takes about 27 days for Sun to complete one complete rotation around its axis. Image of the Sun taken by SUPARCO on Feb 23, 2012 The sunspots appear very small as the Sun is very far from us but actually they could be larger than Earth. Sunspots are produced due to magnetic fields which are twisted like rubber band coming out of the photosphere; the outer most layer of the Sun appearing yellow as we see in noon time. These fields have roots in the convection zone (the region below photosphere) and generated due to charge particle motion. SUPARCO - ASTRONOMY & ASTROPHYSICS Bulletin is a monthly publication View of Sunspots showing Umbral (central dark region) and Penumbral (less darker region) surrounded by granulated surface of the Sun. Page VII Magentic Stroms Monitored by SUPARCO The Space Weather Monitoring Facilities at SUPARCO recorded magnetic storms during Feb. 14-15, 2012 due a Coronal Mass Ejection which erupted on Feb. 9, 2012. The following magnetograms show disturbances recorded by the Abdus Salam Geomagnetic Observatory at Sonmiani. The magnetograms show the disturbed magnetic field, recorded by the Abdus Salam Geomagnetic Observatory at Sonmiani A similar magnetic disturbance was recorded during Feb. 18-22 caused by an Earth-facing Coronal Hole as shown in the magnetograms below. This magnetogram shows disturbance from an earth facing Coronal Hole sending out highspeed solar wind particles starting from late hours of Feb. 18, 2012 The dark area shown in this image taken by GOES-15 satellite’s Solar X-ray Imager (SXI) shows the Coronal Hole CH501 which caused the magnetic disturbance SUPARCO - ASTRONOMY & ASTROPHYSICS Bulletin is a monthly publication Image taken by NASA’s Solar Dynamics Observatory (SDO) shows a magnetic filament erupting Page VIII Venus: Our sister planet Venus is the second planet of the solar system and closest in size to the Earth. Diameter of Venus is only 650 km smaller than the diameter of Earth and it comes within 40 million km of the Earth, nearer than any other planet. It is the brightest object in the sky after the Sun and Moon. The brightness of Venus is because of two reasons; firstly it is closest to us than any other planet and secondly it is entirely covered with thick clouds. These clouds reflect sunlight very effciently even the surface of Venus is not visible through optical telescopes. Venus can be seen in the morning or evening, depending on it position, whether it lies to the west or east of the Sun. These days Venus can be spotted in the western direction. Like our Moon, Venus goes through phases and a small telescope or binocular can easily show these phases. Simulated view of Venus Phase of the Venus shown by software on Jan 19, 2011 Telescopic view of Venus: Image of Venus taken by SUPARCO, through telescope on Jan. 19, 2011 Jupiter Naked Eye view Contact Information Venus is always close to the Sun in the sky usually appearing near the horizon in the twilight. Its brilliance makes it easy to distinguish from adjacent stars. In this picture, taken by SUPARCO on Feb. 23, 2012 Venus is visible in the western sky, another bright point in the figure is Jupiter. Venus Rizla Zareen General Manager 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 This bulliten can be downloaded from the official website of SUPARCO