25 December 2008

Chandrayaan 2 Design Complete

Indian Space Research Organisation (ISRO) said the design for the second moon mission, 'Chadrayaan 2' is completed on December 24th, Wednesday. The mission is supposed to carry a lander/rover whereas the mother spacecraft will orbit the Moon. Chandrayaan 2 is said to be launched on 2012.

ISRO has collaborated with Russia for building the rover. The rover will have a soft landing on the moon unlike the MIP probe of Chandrayaan 1 which had a hard landing. The rover will collect the soil and rock samples from the moon, do in-situ tests and send the data to Earth through the orbiter. The estimated cost for Chandrayaan 2 is said to be Rs. 425 crore (US $ 90 million).

ISRO is currently earning about Rs 10 billion (Rs 1,000 crore) annually from its commercial wing. Chandrayaan is expected make it grow at 20 percent per year.

Anyways, I forgot to mention this in my previous post. The previous one was my 50th post. :)

21 December 2008

W2M Satellite Launched

Another achievement by Indian Space Research Organisation (ISRO) as the satellite "W2M" was successfully launched Sunday morning at Kourou in French Guyana.

Ariane - 5 before launch

Ariane-5 (rocket) was launched on sunday bearing two satellites, "W2M and Hot Bird 9". The space craft W2M, weighing 3463 kg was built by ISRO. This is the heaviest satellite ever built by ISRO and its capable of operating over 15 years. W2M is a communication satellite built on a commercial basis in partnership with EADS-Astrium of Europe.

18 December 2008

Picture Of The Month - December 2008

This is not a very clear image but it is an astonishing one of the crescent Moon and Venus. This was viewed right here at Chennai on May 21st, 2004. It may be old but I would never forget this incident where the Moon forms a magical lamp with Venus brightly light at the end. This image was published in "The Hindu" on the next day. Ever since I started this blog I wanted to post this image but I never found it. By mere luck I found the old newspaper with this image and using its date I found the image in "The Hindu" website. I now hold the newspaper cutting (where the image is clear) as a possession. Click Here to read the article.

A Halo!

I remember my friend Kavin, who use to ask me repeatedly, "What is an Halo and how it is formed?". I had no answer to this question except that I knew it occurs quite regularly. So finally I decided to check on what an Halo is, and this is what I found.

Halos are nothing but a dim circle of light that is formed around the Sun or the Moon or any bright source of light for that matter (eg. a street lamp). These halos are formed due to ice crystals that are found in the clouds. These ice crystals acts as a lens reflecting and refracting the light.

A picture of the Sun's Halo

A Moon Halo

17 December 2008

Geminids Experience

It is the day of Geminids. I had a very long, horrible day throughout. The worst day of my entire life had a happy ending with about 5 meteors. Click here to read the experience of my day. Due to various reasons I reached home as late as 11 pm. I went straight to my terrace at around 11:15 only to find most of the sky covered in clouds. I realized that the clouds were moving very fast and within 10 mins they must clear. Just as I thought the sky was cleared in 10 mins making the sky, around Gemini, clear. The Moon was very bright and I was sure to miss out lots of meteors. I positioned myself such that I could see all around Gemini especially the western part of the sky.

11:39 - South-west, 80 deg from the horizon, a short meteor. Not the brightest.

11:48 - This one was a little to the west from zenith (exactly over-head). It was very quick and very short. It was very quick and also being short, it disappeared less than a second.

11:55 - About 60 deg from the northern horizon, moving towards west. It was a little bright and longer than the previous two.

This was when a bunch of clouds came in. Had to wait a long time for it to clear.

12:15 - About 45 deg from the western horizon. It was less bright but it was quick.

12:30 - About 60 deg from south-west horizon. This one was bright and it moved slowly, about the normal speed with all others being too quick.

The long tiring day started to take over me and I realized I almost dozed at the terrace. I decided to get back into the house and sleep. But it was a good experience.

I hope atleast one of my friends had caught one.

9 December 2008

Geminids 2008

Yet another Meteor Showers. This one is called Geminids. These meteors appear to out of the constellation Gemini, just as Leonids did from the constellation Leo. It can be viewed between December 8th till December 17. But it peaks on December 13-14.

Best time to look out for Geminids is from 9pm on December 13th till sunrise on December 14th. It peaks at about 100 meteors an hour. On non-peak days, you may only spot about 10 an hour. Geminids are one of the best shower of the year. These meteors originated in a mysterious object called 3200 Phaethon, which looks like a cross between an asteroid and a burned-out comet. Each time Earth reaches this point in space, the debris falls into the atmosphere causing the meteors.

Where to look? Look at the entire sky during the time. It can appear anywhere. Its direction would be away from Gemini. For those who feel safe to know the location of Gemini, the constellation is exactly where the moon is on December 13th. And yes! Its a full moon. The bright full moon may block most of the meteors. Hence, you can only see the bright meteors. All the dull meteors will be shunt by the bright light of the moon. So look at the entire sky, best being around the moon.

Click Here to see the position of the moon over Gemini and also how the meteors appear from the constellation. The red "X" on the picture is the radiant of the shower. Radiant is a point from where the meteors appear to move from. No meteor will be visible at the radiant. It only appears to move away from it.

Images Of Venus-Jupiter-Moon Smile

Here are some of the images of the Smile created by Moon, Venus and Jupiter in the sky on 1st December, 2008. Venus and Jupiter forms the eyes and the crescent Moon forms the mouth. The brighter eye to the left is Venus and the one of the right is Jupiter.

The beautiful sky smile over the city of New York.

Through the clouds.

Close-up Shot

It looks perfect here.

This image is hours after the smile. Moon has moved past Venus and Jupiter.

30 November 2008

Venus Jupiter Conjunction

Have a look at the west after sunset tomorrow, December 1st, 2008. You can see the three brightest objects of the night sky very close to each other. The crescent Moon, the goddess of love - Venus, and the king of the planets - Jupiter, are all close together forming a triangle between them. Venus and Jupiter move very close to each other which is called 'Conjunction'. Venus and Jupiter will only be 2 degrees apart.

The above picture is an illustration of the conjunction between Venus and Jupiter and the triangle with the Moon. In India, it can be viewed after sunset and not at 9pm.

Venus is very bright, its magnitude being -4.02 (Lesser the magnitude, brighter the object). Venus can sometime reach the magnitude of -4.6. With the rest of the sky consisting of faint stars, the triangle between the three brightest objects of the night sky will be eye-catching.

23 November 2008

MoonLITE Mission

Britain is set to launch its maiden moon mission to study the phenomenon of mysterious moonquakes, weeks after India's spacecraft Chandrayaan-1 successfully entered the lunar orbit.
The 100-million-pound unmanned mission 'MoonLITE' would aim to understand the cause of mysterious quakes that vibrate through the lunar rock and put it into the satellite's orbit before firing a series of probes into the moon's surface.

The launch of MoonLITE (
Moon Lightweight Interior and Telecommunications Experiment), will be announced next month after which engineers would work on the technical designs with an aim to launch the satellite between 2012 and 2014.

Backed by NASA, the spacecraft would also examine the chemical composition of the rocks and even search for water on the moon's surface.

The existence of moonquakes has puzzled scientists as the moon does not have the tectonic plate activity that causes quakes on the earth.

The MoonLITE mission is expected to fire four suitcase-sized penetrator probes into different points around the lunar surface.

Bright Meteor Over Canada

A huge fireball was seen in the sky on 20th November 2008 over Edmonton, Canada. A video has been captured of this bright meteorite that fell onto Earth. Here is one of the most rarest and the latest video of a meteorite.

Mission Aditya

After the Success of Chandrayaan 1, ISRO has now developed a Sun Mission called 'Aditya'. Aditya has been approved by the government and the work has been started. Aditya is planned to be launched by 2012. Aditya will study the outer most region of the Sun called 'Corona'.

The temperature of the solar corona goes beyond million degrees. From the Earth, corona can be seen only during total solar eclipses mainly due to the bright Solar disc and the scattering of the sunlight by the Earth's atmosphere. One has to go beyond the atmosphere to be able to mask the bright solar disc and study the corona.

Sun's Corona during the Solar Eclipse

"That's a mini satellite. In fact, the design is just getting completed. During solar maxim...which is happening...we would like to see the type of emissions which are taking place in the Sun and how it interacts with the ionosphere and atmosphere and so on. A basic understanding of the physical processes and continuous monitoring would help in taking necessary steps towards protecting ISRO's satellites either by switching them off or putting them on a stand-by mode as warranted by the background conditions.", says Madhavan Nair.

The satellite will remain in Earth's orbit and will study the Sun's Corona, sun spots and the Solar flare. 'Aditya' mission lies behind the international Sun missions 'Yohkoh', launched by Japan, collaborating with US and UK in 1991 and 'Hinode' in 2006. But 'Aditya' will be an Indian satellite with no collaboration.

19 November 2008

Bhuvan vs Google Earth

Yes it is. On March 2009 ISRO will launch its own IRS (Indian Remote Sensing) image portal called 'Bhuvan'. Bhuvan (Sanskrit for Earth) will offer detailed satellite views of our planet just like Google Earth and Wikimapia.

Bhuvan will use a network of satellites to create a high-resolution, bird's-eye view of India – and later, possibly, the rest of the world – that will be accessible at no cost online and will compete with Google Earth. If a pilot version passes muster, Bhuvan will be fully operational by the March. There are also plans to incorporate a Global Positioning System (GPS) into the online tool. Bhuvan will mainly focus on the sub-continent.

Bhuvan has an edge over Google Earth. Bhuvan has a lot more features than the famed Google Earth. Lets compare Bhuvan with Google Earth.

  • Google Earth zooms in upto 200 meters, Wikimapia zooms upto 50 meters but Bhuvan can zoom upto 10 meters. The image is of a very high resolution such that you can get a view from the three storey building.
  • Google Earth is a single layer information whereas Bhuvan is a multilayer information.
  • In Google Earth the images are upgraded every 4 years whereas in Bhuvan, it is upgraded every year.
  • Google Earth has no alternative viewing option. In Bhuvan you have an option of viewing on different dates.
  • Google Earth uses international satellites for mapping but Bhuvan uses Indian satellites.

The prototype of Bhuvan will be ready by the end of November and ISRO is hoping to officially launch the service by March 2009.

ISRO is now booming itself since the launch of Chandrayaan.

18 November 2008

Chandrayaan's First Video

Here is the first video of the Chandrayaan Mission. This video was taken by Moon Impact Probe (MIP), a payload of Chandrayaan - I which had a crash landing on the Moon on November 14th, 2008. MIP took images of the moon as it was descending down to the surface. The 15,000 frames generated by MIP during its 25 mins journey to the moon's surface was decrypted and the complete video is yet to be created. Here is a 2 min part of the video.

17 November 2008

LEONIDS' Experience

Hi. Here I am to share my experience on Leonids 2008. Well, November 17, 2008 is D-day, and here it is. Alarm was set-up at 3:00am on my mobile to start my first meteor hunt (my second actually. My first was 2005 Leonids which I was looking at a complete wrong time and hence failed).

I woke up from a dream (not a nightmare), and discovered that the time was 3:40 and the alarm was off. I didn’t know whether to call myself lucky or unlucky. Went straight to my terrace and I realized that I am, actually unlucky. It was overcast, especially the east horizon. Since the constellation Leo is said to be at the east horizon and that the meteors appear to origin from that constellation, I wasn’t really happy.

Went back downstairs and scanned through the Planetarium Software on my system to find the exact location of the constellation Leo. It was about nearly 4:10 when I decided to go back to my terrace.

I was happy that the sky was partly clear and that the clouds were moving pretty fast. I positioned myself such that I could see the east part of the sky quite clearly. I kept looking there for about 20 mins with no success. During this time I was also trying to identify the constellation Leo. All I could see was two stars near the horizon. At around 4:30 I noticed more stars at the east horizon and I realized that the brighter of the two stars was Regulus (Constellation Leo) and another bright at the dead east was actually Saturn. I decided to go back to my computer to check the planetarium software again and that was moment I would never forget for the rest of my life.

4:32 am – I spotted my first ever meteor. It was to the right of Regulus. It was moving further right away from Regulus. Yes, it was a Leonid and it was moving away from Leo. It was short compared to what I saw in youtube. And quick! Very quick! If I had attempted to blink I may not have caught it after all.

I was really excited. I was literally jumping with joy. Now I noticed that the sky is much clear. I was looking at Sirius, how bright it was; and Orion (my favorite constellation); and the Moon, was really bright. And then –

4:37 amAnother one - To the north of the Moon - Moving towards the west. Again away from Leo (Leo was still at the east). I realized that the meteor may not actually appear near the constellation. Moon was at the constellation Gemini and so was this meteor.

I ran back downstairs and woke up mom. My friend, Kavin messaged me asking if it was worth having a look. Somehow I convinced him to go to his terrace and have a try. Nearly 30 mins later my mom said she was tired and she went back. Bad Luck for her, I thought. A little while later, Kavin messaged me saying it was getting cloudy again and that he was quitting. Bad Luck for him too. I went back to my computer to confirm the location of Leo and Saturn.

Went back upstairs and by now I was really fed up. No meteors in the last 45 mins. I just turned to see if the sky was clear and again –

5:27 am – Another. My third lucky meteor! This one was a little above the north horizon, moving from east to west. Again, away from Leo! This was when I realized how wrong I was. I thought that Leonids would appear near Leo. Now I realized that it can appear anywhere in the sky. The only thing was that it appears to move away from Leo.

Now I decided to stand up and look all over the sky. I was sure I missed a lot of them when I was only looking at east. I’m not gonna miss anymore. 10 mins later I felt I saw a faint meteor near the east horizon. Bright Moon and tiny source of light at the east (rising Sun), it could have really been a meteor but I might have imagined as well.

In another 10 mins light was growing on the east. I realized that I was finding difficult to spot even Orion. All I was able to see on the sky apart from Moon was Sirius, Regulus, Rigel and Saturn. All the other stars had faded due to the growing sun light. That was when I decided to quit my first meteor hunt. Pretty successful. But that’s not the end of the story. Geminids still waiting on December.

15 November 2008

Picture Of The Month - November 2008

Here is a colourful, close-up picture of the Moon taken by Moon Impact Probe (MIP), which is one of the 11 payloads of Chandrayaan-I. MIP was ejected by Chandrayaan on November 14th and had a crash landing (as planned) on the Moon at around 8:31 pm IST. MIP took this picture on its way to the surface of the moon. MIP (with the tri-coloured flag painted on its sides) landed on the Moon, making India the fourth country to make a physical contact on the Moon.

14 November 2008


This is my first post on Meteoroids and I am going to help you guys catch a Meteor Shower. In 3 days time you can catch Leonids, on 17th November, 2008. Before guiding you through that let me explain what a meteoroid is.

Meteoroids are tiny rock particles found in space. It may be broken asteroids or remains of a comet. It is smaller than asteroids and they do not have a definite orbit. When a meteoroid enters the Earth's Atmosphere it is called a Meteor. And when it hits the ground it is called a Meteorite. Smaller meteors gets burned up when it reaches the atmosphere hence not all meteors reaches the ground. Meteors are more famously called as 'Shooting Stars' or 'Falling Stars'.

A Meteor or a Shooting Star

Meteor Shower is an Astronomical Event when many meteors are observed at the same point of region in the sky on the same night. If the night sky is clear and if the moon is not too bright, you may even catch up about 50 meteors. Let us see what causes the Meteor Shower.

When a comet moves closer to the Sun, some of its ice particles and debris remains. When Earth passes through the same region in space most of the debris fall into the Earth's atmosphere causing Meteors Showers. This is an annual event. Every year when Earth passes through the same region you can notice many meteor showers.

One such Meteor showers can be noticed on 17th November. This Meteor Shower is called as Leonids. Leonids occur every mid november. As mentioned earlier all the meteors appears to come from the same point on the sky. In this case all the meteors appear to come from the constellation of Leo, hence the name. This can be easily explained by this picture.

The above picture shows the constellation of Leo and how the meteors appear to come from the same point.

So wake up very early on the morning of November 17th, and keep looking into the sky near the constellation of Leo. Use Stellarium Software to help yourself find the constellation of Leo. At an average you may spot 10 to 15 meteors an hour. Even if you cannot spot Leo, just keep looking up at the sky between 3:30 am until sunrise. You should be able to catch quite a few meteors.

NOTE: You need to be really patient if you want to catch some meteors. Hope the clouds and the Moon won't spoil the show. And the meteor can be quick that you can easily miss it. So watch carefully.

View this video to get an idea on how you actually see it. Note that this is a fast forward.

I haven't seen a Meteor yet. This is the first time I'm going to hunt for meteors. I hope I'm successful and you too.

8 November 2008

Successfully in Orbit

Chandrayaan - I has successfully entered into the Lunar Orbit today at around 5 pm IST.

Chandrayaan - I was launched on October 22nd, 2008. After its launch the space craft was put into the Earth's orbit, taking an elliptical path of 22,860 km as apogee (farthest point from the Surface of the Earth) and 255 km as perigee (nearest point from the Surface of the Earth). Since then the space craft was propelled, increasing its distance from Earth and nearing the Moon. Its final orbit around the Earth had an apogee of 3,84,000 km and perigee of 1,019 km until Lunar Orbit Insertion (LOI) started at around 5 pm for about 800 secs.

LOI is when a space craft is propelled so that it shifts from Earth's Orbit to the Lunar Orbit. At LOI the Earth and the Moon's gravitational force are almost equal. LOI is always a danger since even a small deviation by the space craft would make it crash into the Moon's surface or the Earth's surface or out into the deep space. Experts recall that about 30% of the unmanned moon missions by NASA and Soviet Union have failed during LOI.

Chandrayaan, after completing LOI at around 5:15 pm, is now making an elliptical orbit around the Moon with 7,500 km as aposelene (farthest point from the Surface of the Moon) and 500 km as pericelene (nearest point from the Surface of the Moon). Chandrayaan will further reduce its distance from the Moon to merely about 100 km. This may probably happen on November 14th or 15th.

4 November 2008

Picture Of The Month - October 2008

These are the first images of Earth taken by Chandrayaan-I on October 29th, 2008 using Terrain Mapping Camera (TMC) which is one of the 11 payloads of the spacecraft. The first image was taken at 8 am at a height of 9,000 km showing Northern coast of Australia. The second image was taken at 12:30 pm at a height of 70,000 km showing southern coast of Australia.

22 October 2008

Plans of Chandrayaan-II

After the success of India's first unmanned moon mission ISRO has now proposed its second odyssey to the moon, Chandrayaan-II will be launched by the end of next year or early 2010. Initially, the plans of Chandrayaan-II was that it would be launched by the end of 2010 or early 2011. But the success of Chandrayaan-I has pre-poned the launch of Chandrayaan-II.

PSLV C-11 Rocket being launched today morning bearing Chandrayaan-I

Chandrayaan-II is an Indo-Russian joint venture. Russian federal space agency have already signed a pact with ISRO. "One of the two GSLV missions next year will carry Chandrayaan-II", says ISRO Chairman Mr. G. Madhavan Nair.

Chandrayaan-II would feature a lander and a rover for a soft land on moon. The rover will be designed by Russia’s federal space agency. India may be the second country to land a rover on the moon after USA during NASA's Apollo missions.

Mr. Nair expects more accomodating payloads (experiments) from other space agencies for the second odyssey just as in Chandrayaan-I. Chandrayaan-I carried 11 payloads of which 5 are Indian, 3 are from the European Space Agency, 2 from the NASA and one from Bulgaria.

"Even though China's and Japan's moon satellite (which are still in Moon's orbit) took high resolution pictures of the moon, they aren't as comprehensive as Chandrayaan-I", says former NASA associate administrator Scott Pace. The budget of Chandrayaan-I is also considerably cheaper than that of Japan or China.

This also strenghtens the space race in Asia. Japan, China and now India have successfully launched moon missions. China is leading in the race ever since they put taikonauts (Chinese Astronauts) in space in 2003 and had their first space walk last month. Even though this is India's first space expedition beyond Earth's orbit India is quickly catching up with China. India might even successfully land a rover and also humans on the moon's surface even before China.

Chandrayaan in Orbit

India becomes the sixth country (after Soviet, USA, European Space Agency, Japan and China) to launch a satellite to the moon as Chandrayaan-I has been successfully placed in its orbit around Earth. The PSLV with the satellite was launched at the designated time and the path of the rocket was perfect as planned. Chandrayaan will orbit earth for a few days and then head its way to the Moon. It will be expected to reach the Moon on November 5th.

Chandrayaan was launched at 6:22am today and by 18 mins the satellite was put into orbit. So far there has not been a problem in the satellite or the rocket. The rocket projected through the designated path perfectly and ISRO says it has hit a “Bull’s Eye”.

I was eagerly waiting with a camera to shoot a video of the rocket on my terrace. Unfortunately over-cast did not help me at all. Thick clouds blocked the view of the rocket completely.

PSLV C-11 with Chandrayaan on its way to the Launch Pad

PSVL C-11 ready for the launch

I will be constantly updating on the Chandrayaan mission and hope that it will successfully reach the moon’s orbit which is due in two weeks time.

20 October 2008

Mission Chandrayaan

Indian Space Research Organization (ISRO) reaches a new peak in their mission. In two days time Chandrayaan-I will be launched at Sriharikota on October 22, 2008 at exactly 6:20am IST.

Chandrayaan-I is an un-manned lunar spacecraft (meaning it carries no human). The spacecraft (Chandrayaan-I) will be launched by a modified version of Polar Satellite Launch Vehicle (PSLV-C11). The lunar probe would revolve around Moon for two years taking high resolution images of the lunar surface and also mapping its chemical and mineralogical content. It also concentrates on the polar region where water and ice could possibly be found. The satellite weighs about 1304 kg and the estimated cost is about INR 3.8 billion.

Chandrayaan-I under construction

The scientific payloads/experiments of Chandrayaan are TMC, HySI, LLRI, HEX, MIP, C1XS, SIR-2, SARA, RADOM, MiniSAR and M3. Click here to know more about them.

The Path of Chandrayaan

The Moon Exploration began on September 14, 1959, when Luna 2 was launched by Soviet Union. Since then USA, Japan and China have also successfully launched spacecrafts to the moon. This is India’s first mission to Moon and India will be the sixth country to send a spacecraft there. USA is the only country that has successfully sent man to during the Apollo Missions (1963-1972).

Chandrayaan-I will be followed by Chandrayaan-II in 2010/11. Chandrayaan-II will consist of the spacecraft itself and a landing platform with the Moon Rover. A moon rover is an automated motorized vehicle which moves around the surface of the moon, collecting soil and rock samples, do in situ chemical analysis and transmit it to the mother-spacecraft, Chandrayaan-II. USA has already used the lunar rover during their Apollo missions (Apollo 15 - 17).

A artistic representation of the Chandrayaan-II rover

The Lunar Rover of Apollo 15 with James Irwin

ISRO also plans to undertake a manned space exploration by 2014 (send man to space). India would then become the fourth country to send man to space after Soviet Union, USA and China.

If these missions succeed, then ISRO plans to send a manned mission to the moon on 2020. If ISRO succeeds in this, India will be the second country to land man on moon.

Meanwhile China plans to land a rover on the moon on 2012. China has entered into an agreement to work with Russia to eventually land Taikonauts (Chinese Astronauts) on the moon before 2020. So its all a race between India and China on who will reach there first.

I just hope all this works out for India as the countdown for Chandrayaan-I has begun.

Chandrayaan-I is ready for the launch

People who live in Chennai can actually see the launch of Chandrayaan-I. Look at North at the exactly 6:20am on October 22nd. You should be able to see the rocket shooting upwards provided the clear sky.

1 October 2008

Picture Of The Month - September 2008

This picture was taken on September 1st, at Perth, Australia. This evening picture shows the crescent Moon along with three planets. The brightest of the three is Venus as the Evening Star. The tiny shining object above Venus is Mercury and the object at the top most is Mars. The three planets are found on the western sky after the sunset. This picture was taken across the Swan River and the six towers on the left of the image surrounds the Perth Cricket Stadium.

10 September 2008

Big Bang Recreation???

European scientists are taking the initial steps in what has been described as the most ambitious scientific experiment the world has ever seen.

At a purpose-built underground centre by CERN near Geneva, Switzerland, the scientists are carrying out limited tests on a multi-million euro machine called the Large Hadron Collider.

The ultimate aim is to recreate conditions that existed immediately after the Big Bang.

The team hopes to pinpoint dark matter, the name given to unseen particles thought to exist all around us and throughout space.

The experiment, which began at 8 am this morning Irish time, involves smashing protons - one of the building blocks of matter - into each other at velocities only a fraction less than the speed of light.

In the flashes from the collisions, scientists expect to reproduce conditions that existed during the first billionth of a second after the Big Bang at the birth of the universe.

Large Hadron Collider

Details on the on-going experiments will be posted very soon.

31 August 2008

Picture of the Month - August 2008

Do you see a Sun Spot on the Sun??? Click on the Picture to see it in a larger resolution. You can now clearly see that its not a Sun Spot but a space Station. It is the International Space Station (ISS) trasiting the Sun. As the ISS moves around the Earth, the space station (very rarely) appears to move across the surface of the Sun as in this Picture.

16 August 2008

Solar Eclipse

If you had read my previous post on Occultation you would have known that Solar Eclipse is also an Occultation. Solar Eclipse is nothing but the effect of Moon occulting the Sun.

The Moon revolves around the Earth just as Earth revolves around the Sun. Moon takes approximately 30 days to move around the Earth. During this revolution the Moon comes in between the Earth and the Sun once every 30 days which we call as New Moon. On certain New Moon days the Moon is exactly in between the Earth and the Sun such that the Moon blocks the sun light, thus creating a shadow on the surface of the Earth. The Moon appears to move across the surface of the Sun when viewed from those shadowed area. This phenomenon is known as Solar Eclipse.

The Shadow of the Eclipse on the Earth

There are three types of Solar Eclipse.

Partial Solar Eclipse:

When viewed from Earth the Moon blocks a part of the Sun and does not block it completely. This is known as Partial Solar Eclipse. The region under the penumbra experiences the Partial Solar Eclipse. Partial Solar Eclipse is not dangerous to view at all. But continuous view of Sun can create some damage to the eye and hence it can be viewed through any Sun Glass.

A view of Partial Solar Eclipse

Total Solar Eclipse

This occurs when the Moon completely blocks the Sun letting no light reach the Earth. The region under the umbra experiences the Total Solar Eclipse. The total Solar Eclipse begins with the partial eclipse with the Moon moving slowly across the surface of the Sun until it completely blocks the Sun. For about a minute the sky would be dark. Then as the Moon continues to move a bright light comes out from one end of the Sun which looks like a Diamond Ring and hence it is called so. Since a great amount of light comes in within a fraction of a second it can blind us permanently when tried to view. Total Solar Eclipse can be viewed using a special google created for the eclipse.

Formation of Total Solar Eclipse

The Diamond Ring Effect

Annular Eclipse:

This is the most rarest of all eclipses. This occurs when the Moon is farthest from Earth during the eclipse. This occurs when the shadow of the Sun could not reach the Earth or when the Earth is at antumbra. The Moon appears smaller than the sun when viewed from Earth and hence at a Total eclipse the Moon does not block the Sun entirely but only the center portion of it. The outer surface of the Sun is clearly seen.

Annular Eclipse

The following image explains more about the Umbra, Penumbra and Antumbra and the reason why we experience partial, total or annular eclipse.

Umbra, Penumbra and Antumbra

India experienced a Partial Solar Eclipse as recently as August 1st, 2008. And that was the day I heard so many rumors about the Eclipse which were not true. I tried telling my friends but none believed me. But I would like to share it to all so that none would believe such rumors next time.

Some of them were very scared that staying outside on such days will affect their health. The only trouble Solar Eclipse gives us is blinding us only when we look at the Sun at a perfect Total Solar Eclipse. Watching a Partial Solar Eclipse is like watching the Sun any other day which does not create much damage except by continuous looking at it.

One such friend of mine didn't have his lunch saying that he heard that people should not eat during a Solar Eclipse in a News Channel. Later when I viewed the same channel I realized that it was a superstitions that was brought out by the News Channel. In reality Solar Eclipse does not change our body mechanism by any way and hence we need not lose our appetite on the eclipse day.

The best of all was a conversation between two girls that i over heard as I was walking on the road. As it started drizzling i heard them talk.
Girl 1: Oh God!! Its about to rain.
Girl 2: It cant rain today. Its Solar Eclipse.
What's Solar Eclipse got to do with the clouds or rain? Its simply rumors and people need not be fooled by such things. Solar Eclipse does not create any damages to us other than blinding us.

The next Total Solar eclipse in India occurs on January 26th, 2009 and the next Annular Eclipse occurs on January 15th, 2010.

9 July 2008

Picture of the Month - July 2008

Here is a beautiful picture of Venus transitting Jupiter. This one is not an original picture. This is a screen shot from the Stellarium software. Do you want to view this in stellarium? Set your location to Chennai (India) and the date and time to November 22nd, 2065, 6:11pm. Click on either Venus or Jupiter and zoom in to see the beautiful transit. Venus transits only between 6:07 to 6:15 pm IST.

NOTE: Don't forget to turn off the ground and the atmosphere.

20 June 2008


Here is yet another Astronomical Term - Occultation. Sounds weird but a simple term. An occultation is an event that occurs when one object is hidden by another object that passes between it and the observer. Does it sound familiar? Yes! Eclipses and Transits are also known as Occultations.

Every object in space move in a particular direction. By coincidence any two objects may come in the same line of sight from Earth which causes Occultation. The most famous occultation is the Eclipse.

Total Solar Eclipse

In case of Solar Eclipse, the Moon comes in between the Sun and the Earth. Hence the Moon and the Sun are in the same line of sight. The Moon appears to block the Sun from the view or the Moon occults the Sun.

But this is not the case in the Lunar Eclipse. In Lunar Eclipse it is the Earth that occults the Moon when observed from the Sun and not from the Earth. Hence Lunar Eclipse cannot be called the Occultation.

Position of the Earth, Sun and the Moon during the Total Solar Eclipse (left) and the Lunar Eclipse (right)

The term Transit is used when one object appears to move across the face of another object. Usually one of the object is small when compared to the other. The most famous transits are that of Mercury and Venus over the Sun.

Transit of Mercury over the Sun

Transit of Venus over the Sun

Enlarged Image of the transit of Venus

Transit of Io (Satellite of Jupiter) over Jupiter

The other types of occultation are when a star occults another star or when a satellite occults another satellite. This can only be observed through telescopes.

Dione (Satellite of Saturn) occulting Rhea (satellite of Saturn)

Another rare type of occultation is when a planet occults another planet. It is not seen very often. Here is the list of occultation by planets that occured in the past and the ones which will occur in the future.

* 19 Sep 1702 - Jupiter occults Neptune
* 20 Jul 1705 - Mercury transits Jupiter
* 14 Jul 1708 - Mercury occults Uranus
* 4 Oct 1708 - Mercury transits Jupiter
* 28 May 1737 - Venus occults Mercury
* 29 Aug 1771 - Venus transits Saturn
* 21 Jul 1793 - Mercury occults Uranus
* 9 Dec 1808 - Mercury transits Saturn
* 3 Jan 1818 - Venus transits Jupiter
* 22 Nov 2065 - Venus transits Jupiter
* 15 Jul 2067 - Mercury occults Neptune
* 11 Aug 2079 - Mercury occults Mars
* 27 Oct 2088 - Mercury transits Jupiter
* 7 Apr 2094 - Mercury transits Jupiter
* 21 Aug 2104 - Venus occults Neptune
* 14 Sep 2123 - Venus transits Jupiter
* 29 Jul 2126 - Mercury occults Mars
* 3 Dec 2133 - Venus occults Mercury

A simulation of Venus transiting Jupiter, as it did on January 3, 1818.

Occultation can also occur in other types such as Moon occulting a star, Moon occulting a planet, Planet occulting a satellite, etc.

Minutes before the Moon occulted the star Albedaran

Before Moon occults Jupiter

Jupiter occulting Europa (Satellite of Jupiter)

The most recent occultation took place on 10th May, 2008 when the Moon occulted the planet Mars at around 8pm IST. It was clearly visible even at Chennai.

1 April 2008

Picture of the Month - March 2008

Blasting into a dark night sky, the Space Shuttle Endeavour began its latest journey to orbit in the early morning hours of March 11. In this stunning picture following the launch, the glare from Endeavour's three main rocket engines and flanking solid fuel booster rockets illuminates the orbiter's tail section and the large, orange external fuel tank. Embarking on mission STS-123, Endeavour left Kennedy Space Center's pad 39A, ferrying a crew of seven astronauts to the International Space Station (ISS). The cargo included the first section of the Japan Aerospace Exploration Agency's Kibo laboratory and the Canadian Space Agency's two-armed robotic system. Astronauts will conduct a series of space walks to install the new equipment during the 16-day mission, the longest shuttle mission to the ISS.

7 March 2008

Planetarium Software

Interested in Astronomy? Love to look into the night sky? Being an amateur you would find it very difficult to identify stars and planets and other stuffs. But it can be made easy using certain Planetarium Softwares. These softwares show you how a night sky may look like at any time from any place. These softwares label every star so that you can identify it in the sky easily using the software. There are many such softwares available in the internet. I came across one such software which is very user-friendly.

Stellarium 0.9.1 is a free open source planetarium for your computer. It shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope. It is being used in planetarium projectors. You can set your coordinates such as your location and time zone and look through the night sky. This software also shows you the planets, nebulae, galaxies, comets, meteors, etc. Every star, planet or a galaxy is labeled which makes it user-friendly. You can zoom into any stars or planets to know how it looks like in a telescope. You can also see the night sky of any time at any year. It even shows you the night sky of the year 2100.

Here are some of the Screen Shots of the software.

The full view of the constellations.

A shooting star passing near the Moon.

A zoomed in view of the Planet Jupiter.

A zoomed in view of a nebula.

You can download this software from this website.