I just now spoke to an ISRO scientist and was informed that the video of the moon taken by the Terrain Mapping Camera (TMC) of Chandrayaan-1 is NOT a 3D version but a video from a sigle view.

I am sorry for wrongly stating in my post last evening (Nov 17, 2008) that it is a 3D view.

The Terrain Mapping Camera can image a single surface feature on the moon from three different views.  Though combining two views can help produce a 3D picture, combining all the three views can help compile a much superior 3D atlas.

One can easily identify a crater even from a single view based on the shadow effect.  So imagine the quality of a 3D picture when all the three views are combined.

ISRO has a fantastic 3D video of moon posted in its website.  The 2.30 minutes video was taken by the Terrain Mapping Camera (TMC). It was taken as Chandrayaan-1 flew past the area near the South polar region of the moon. 

The video is taken from a height of 100 km from moon’s surface.  It has a spatial resolution of 5 metres.  Terrain Mapping Camera combines the data of a point taken from three different views to get a high-resolution 3D image.  The first of its kind video of the moon in the world.

 It is best seen at normal zoom and not in full-screen zoom.

UPDATE: The video is NOT a 3D version but a video from a single view.  The Terrain Mapping Camera can image a surface feature from three different views.  Combing these 3 views will help produce a superior 3D atlas of the moon.

My latest top posts are:

1) Pictures taken by the Moon Impact Probe

2) Pictures taken by the Terrain Mapping Camera from the 100-km orbit

This picture, taken by Chandrayaan-1’s Terrain Mapping Camera on Saturday, shows many large and small craters on the Moon’s polar region. The bright terrain on the lower left is the rim of the 117-km wide Moretus crater.

This is the first picture of the moon taken by the Terrain Mapping Camera (TMC) on Nov 15, 2008.  It was taken when Chandrayaan-1 was on moon’s polar region. The picture shows the rim of the 177- km wide Moretus crater.

One Nov 13, it took several pictures of the equatorial region of the moon.  A part of the Torricelli crater was also pictured.

The Terrain Mapping Camera (TMC) also took several pictures on Nov 13  The picture shows a part of the equatorial region, including the Torricelli crater on.  

This is the picture of moon's surface taken from lunar orbit by Chandrayaan-1 spacecraft's Terrain Mapping Camera (TMC) on November 13, 2008. Taken over the equatorial region of the moon, the picture shows the uneven surface of the moon with numerous craters. On the lower left, part of the Torricelli crater is seen.

The Hindu has a report on another payload of Chandrayaan-1 — Lunar Laser Ranging Instrument (LLRI) – being switched on.  It works on the same principle of a sonar that is used to measure the height/distance of objects from the instrument.

LLRI can help scientists find the height of mountains and depth of craters and valleys very accurately. If the signal comes back to the instrument earlier than for a 100-km distance, it will mean that there is a mountain or an elevated structure.  Likewise, if the signal comes back late, it will mean that the region being studied is a crater or a valley.

This data will be combined with the data got from the Terrain Mapping Camera, and will help in understanding the topography of the moon accurately.  It will also help in understanding the internal structure of the moon and its origin.

The LLRI will be able to take 10 measurements per second. And the data will be collected throughout the day.  Unlike the Terrain Mapping Camera (TMC), the LLRI does not depend on light conditions to take measurements.

My latest top posts are:

1) 3D video of moon taken by Terrain Mapping Camera

2) Pictures of moon taken by Moon Impact Probe

The first 3D image of the moon taken by Chandrayaan-1 will be processed  tomorrow (Nov 17, 2008).  The image captured by the Terrain Mapping Camera (TMC) will be from the region around the moon’s equator. 

(UPDATE:  ISRO has posted the 2.30 minutes 3D video taken by Terrain Mapping Camera)  

This is the first time in the world that a 3D atlas of the moon with a very high resolution of 5 metres will be created.

In a piece that I wrote in the The Hindu,  I had explained the principle behind TMC. 

The images taken by the Terrain Mapping Camera will help create a 3D view of the moon.  This becomes possible as TMC will capture a single region from 3 different angles simultaneously although it uses only a single camera. 

The Terrain Mapping Camera captures a single point from three different angles using a single camera.

Though the time taken to complete one orbit will be 2 hours, the moon will be imaged only for 20 minutes per orbit.  This is because the moon will imaged only when it is well illuminated by sun.  This applies only to the regions lying 30 degress on either side of the zero latitude.

Again the moon can be imaged continuously  only for 60 days in 6 months.  So in a year there can be only 120 days of imaging of the moon.

The higher latitute regions, including the poles will be imaged when the lower latitudes are not imaged.

Another picture of the moon taken by the Moon Impact Probe on Nov 14, 2008.

These are the two pictures taken by the Moon Impact Probe (MIP) on its way to the moon before crashlanding on the moon’s surface

close-up photograph of the Moon’s surface taken by the video camera of the Moon Impact Probe on Friday (November 14, 2008) as the MIP approached the Shackleton crater after separating from Chandrayaan-1.

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Today’s The Hindu has two pictures of the moon after  the moon impact probe (MIP) was separated from Chandrayaan-1and was travelling towards the Shackleton crater on  the moon. The ISRO has also posted these two images.

When the Moon Impact Probe (MIP) bid goodbye to Chandrayaan-1 at 8.06 pm (IST) and said Hello to moon at 8.31 pm today (IST), India arrived.  One small impact on the moon, a giant leap for India.

The moon impact probe crashlanded on the moon at 8.31 pm.  Ejection was perfect at 8.06 pm.  Travelling for 25 minutes at a speed of 1.6 km per minute, the MIP crashed on the moon’s south pole.

It was the Shakelton crater in the south pole that ISRO wanted the MIP to crash and it did just that.   On the dot with expreme precision.  

This is the second instance when ISRO proved with Chandrayaan-1 that it could do things at such high precision, never before accomplished by other countries.  The first was when the lunar transfer happened within 10 km of the targeted orbit.  Other countries were hundreds of kilometres off the mark.  And many of USSR’s and US’ spacecrafts had flown past the moon without being captured by it.

The Indian flag may not flutter.  Well, flags cannot flutter on the moon as it has extremely thin atmosphere and no breeze.  And it is a different matter that the US flag was seen fluttering in the background after it was planted by Neil Armstrong!  The Indian flag was painted on the MIP.  It had sanskrit sloga written on it, as well.

And while other countries have all targeted the equator, Chandrayaan-1 took the MIP to the south pole.  And the reason is obvious. If others could not find water ice at the equator, it only makes sense to look at other places.  And the poles have a better chance of having it.

And if there is no water ice, then the presence of life is remote, almost impossible.  That is the reason why all space missions to Mars have been looking for water.

It has already sent data to Chandrayaan-1.  Chandrayaan-1 will send the data tomorrow morning when it comes in direct sight of the antenna in Bangalore.

It should have collected data of the extremely thin atmosphere and taken photos of the moon till it crashlanded.  

The camera used is an ordinary industrial one that is commercially available.  The Space Applications Centre at Ahmedabad did not make one as the commerically available  one was good enough. The main requirement was that it should be robust and be able to function under such demanding conditions.

Rocket science is the pinnacle of science.  And if timings and distances, among others are critical, then ISRO has passed the litmus test. 

First it was the fast breeder nuclear technology that helped prove that it has matered the technology.  And now it space science.

There will not be three more orbit manoeuvrings but just two more. 

Chandrayaan-1, which was fired to its first lunar orbit yesterday, will be again fired tonight.  But instead of reducing the orbit from 7,500 km to 250 km aposelene, it will be reduced to a circular orbit of 200 km.  The next firing, which will happen tomorrow afternoon, will see the spacecraft reach the targeted 100 km circular orbit.

So the moon impact probe will hit the moon tomorrow afternoon.  And images of the moon using the terrain mapping camera to help compose a 3D atlas will start functioning from tomorrow.

The most difficult part of manoeuvring Chandrayaan-1 to the lunar orbit has been successful. This was done around 5.30 pm today (Nov 8). 

This is difficult part of the entire manoeuvring process as the Chandrayaan-1’s velocity has to be first reduced by reverse firing when it reaches about 500 km from the moon.  If the velocity reduction does not happen at the right time at the right place then it will be lost for ever as it would neither be in an elliptical orbit around the earth nor a hyperbolic orbit around the moon, as the report in today’s  The Hindu states.

Once it is captured by the moon, the orbit become a polar elliptical one around the moon.

The next few operations will be to reduce the orbital height in four stages.  This is not very difficult.

About 6 pm tomorrow, Chandrayaan-1 would have reached about 500 km from the moon and  it would have be fired to take the spacecraft to its initial orbit around the moon.

The initial orbit will have 7,500 km apolune (farthest point from the moon) and 500 km perilune.  The perilune will be the point where the firing takes place.  The moon’s gravity will take over fully the very moment this firing happens at 500 km.

The speed of Chandrayaan-1 will be reduced further by reverse firing (Chnadrayaan-1 will be reversed 180 degrees while orbiting and then fired.  This will help reduce the speed of the spacecraft).

Once the reverse firing happens, the perilune will be reduced to 125 km while the apolune will remain the same at 7,500 km.  This will the first lunar orbit.

The second lunar orbit will have a perilune of 125 km and 250 km apolune.  The third orbit will have a perilune of 100 km and apolune of 250 km.  The final circular orbit will be 100 km from the moon.