Cartosat 2B launch scheduled for 12th July 2010

SSSalvi · Post by **SSSalvi** » 27 Apr 2010 20:07

High resolution satellite Cartosat 2B ( successor to Cartosat 2A ) is readying for launch on 9th May 2010 tentatively scheduled @ 9:23 IST .

http://economictimes.indiatimes.com/art ... 860701.cms

Searched for this topic in forum ( requirement to start a new topic to avoid repeatation ) but could not find one ... hence taken liberty to start the new topic.

Yours truly was Operations Director for Cartosat 2A so the urge to start this topic.

manjgu · Post by **manjgu** » 27 Apr 2010 20:47

SSalvi...Great to have you on board..

So what additional capabilities will the new sat offer ? and were we able to fully exploit capabilities of Cartosat A ??

Bade · Post by **Bade** » 27 Apr 2010 23:00

Will repeat what I asked in the other thread.

For all polar missions what are the plans in ISRO for data acquisition for each and every orbit for the entire mission life of the satellite ? I do not see that adequately addressed in any brochure or sound bytes.

Prem Kumar · Post by **Prem Kumar** » 28 Apr 2010 00:16

SSSalvi: thanks for starting this thread. If you know some highlights of 2B, can you plz share them? I've read in some reports that it has a new steering system for high agility (I guess for peering over a certain spot for longer).

As regards resolution, is it really 0.8m or is it deliberately downplayed? If it is the former, then its a touch disappointing, given that even TES launched nearly a decade ago had a 1m resolution. If it is the latter, it is difficult to understand the reasons for the same, given that commercial satellites like QuickBird today offer a 0.6m resolution.

Would appreciate your insights.

Neela · Post by **Neela** » 29 Apr 2010 19:34

Cartosat 2B launch rescheduled!

"A marginal drop in the pressure in the second stage of the vehicle was noticed during mandatory checks carried out on the PSLV-C15 vehicle," the Bangalore-headquartered Indian Space Research Organisation (ISRO) said in a statement here.

Gagan · Post by **Gagan** » 29 Apr 2010 19:53

1. What's the resolution on this one.
Please some give me a figure better than 55 cms. (That was ages ago for the TES)

2. Does this take images in other spectra? There was a paper that mentioned that scanning in several spectra will render all attempts at camouflage futile.

3. Will some jingo who works for RAW and ISRO and the Army please please mail me one of the high resolution images? I'll tell you my address and please can you take a picture of my house? The image quality on google earth is miserable.

Bade · Post by **Bade** » 29 Apr 2010 21:29

Gagan wrote: 3. Will some jingo who works for RAW and ISRO and the Army please please mail me one of the high resolution images? I'll tell you my address and please can you take a picture of my house? The image quality on google earth is miserable.

You can make your request directly to NRSA in Hyd'bad with your lat-lon box around the house and purchase the data.

SSSalvi · Post by **SSSalvi** » 29 Apr 2010 22:18

Following statement needs to be understood.

-----------------------
There is one satellite Cartosat 2 ( plain 2 not 2A ) which was the first high resolution satellite in aam aadmi domain.

Then there was Cartosat 2A of which we just heard that it was launched and that its imaging system was operating normally. Afterwards there is nothing that can be heard by aam aadmi. I can only say that it is working and is very heavily loaded with tasks.

Now its brother Cartosat 2B will be launched and in the same fashion we will not know later what happens.

----------------------

All the the three have high resolution .. and by using various image acquisition modes ( permutations of acquisition speed, step and stare manipulations etc it is possible to acquire even sub-meter ( Carto 2 was even used to acquire images of .4 and .2 M for TEST PURPOSE ONLY ) resolutions [ A tongue in cheek statement , will not be elaborated further in future discussions - " provided the imaging system does not have any optical aberrations" ].

Gagan : are you not staying in a city? Most of the cities are covered nicely in google earth / wikimapia. Any normal house is clearly visible ( including trees around it ) and NO indian satellite can give better or comparable resolution than that .

PratikDas · Post by **PratikDas** » 30 Apr 2010 01:43

SSSalvi wrote: ...
Any normal house is clearly visible ( including trees around it ) and NO indian satellite can give better or comparable resolution than that .

Could you please share with us if the technological gaps between our current capability and the best Google Earth resolution are understood and if it is only a matter of time before we achieve the same, or are there some black-art missing-link technologies?

nits · Post by **nits** » 30 Apr 2010 13:00

Launch postponed to June...

http://timesofindia.indiatimes.com/indi ... 875446.cms

Gagan · Post by **Gagan** » 30 Apr 2010 13:38

I live on the outskirts in peace and tranquility.

The image quality of google earth sucks around the area I live in !!!

What to do, moi boor humble abode not in soopar high res!

SSSalvi · Post by **SSSalvi** » 30 Apr 2010 16:08

PratikDas wrote:
SSSalvi wrote: ...
Any normal house is clearly visible ( including trees around it ) and NO indian satellite can give better or comparable resolution than that .
Could you please share with us if the technological gaps between our current capability and the best Google Earth resolution are understood and if it is only a matter of time before we achieve the same, or are there some black-art missing-link technologies?

Over most of the Indian subcontinent Google Earth ( GE ) has about a meter resolution. We don't have imageries from Indian Satellite of that resolution in PUBLIC DOMAIN, I repeat PUBLIC DOMAIN . That is the reason why you can't get better resolution with Indian Data base " Bhuvan".

Basically there is no reason why we can't attain better resolutions but then there are certain hurdles:

1. The basic sensor ( CCD array ) is not off the shelf item.. space qualified CCD arrays are costly and the manufacturers can be arm-twisted by their respective govts and there are many polite ways of saying that the production is presently not possible or a similar answer.

2. There is no lack of technical knowledge in the country about how to acquire hi-res images ( if the hardware is available. )

3. Even if you do manage to get some 'photographic material' ( let's not call it CCD ) , you require very fine optical system and a stable platform from which you need to acquire images.
As regards stability of the platform we should understand that there are hundreds of moving components onboard and even as small a impulse as switching a relay can create a wave in otherwise steady state image. There are gyros, antenna pointing mechanism etc. One of the biggest component to give vibrations is solar array which has to be pointed to the sun continuously or you have to have a sufficient storage power which can be used for the duration of imaging. ( even after you stop the solar array .. the stopping action turbulence ( inertia ) stays for a good few seconds ) .

4. Then there is a philosophical view. DO YOU REALLY REQUIRE HIGH RES IMAGES FOR EVERY NOOK AND CORNER??? Where required you can use hi-res but not all the places.
This is because the technique of high res imaging does not allow large strips of images .. basically the data can be acquired over small araes of about 10X10 or similar sq kms. This is due to the technique known ' step and stare ' wherein the camera keeps scanning the same area for a longer duration than its speed. ( In other words to acquire a strip of say 12 kms length the camera has to look to the scene for about 6 to 8 second i.e. about 8*7 = 56 kms of the physical travel of spacecraft linear forward direction. After that imaging is over the camera has to again retrace back to starting position to acquire next image and we have to wait for this retrace turbulence to die before the next image acquisition starts.

I have tried to give some basic hurdles which one can think of.. this is not an exhaustive list.

We are not lagging behind due to some black areas in the knowledge .. we have upto date knowledge and expertise if proper resources are not blocked.

SSSalvi · Post by **SSSalvi** » 30 Apr 2010 16:18

Gagan wrote:I live on the outskirts in peace and tranquility.

The image quality of google earth sucks around the area I live in !!!

What to do, moi boor humble abode not in soopar high res!

Aap to khud GAGAN ho to phir ye sab outskirts aapke liye kya hai??

K Mehta · Post by **K Mehta** » 30 Apr 2010 16:59

salvi ji, our gratitude for working on carto!
also nice to get your unelaborate-able thoughts!

interesting that you dont mention the previous experimental satellite TES!

PratikDas · Post by **PratikDas** » 30 Apr 2010 18:35

Thank you, SSSalvi, for taking the time put down your thoughts and facts. Enlightening stuff!

Best of luck with the launch!

SSSalvi · Post by **SSSalvi** » 04 Jul 2010 21:46

The Indian Space Research Organisation (Isro) will launch Cartosat-2B, its most advanced remote sensing satellite, on July 12 .

Mr S. Satish, chief spokesperson, Isro, said that preparations were in full swing to launch Cartosat-2B.
“PSLV-C15 will blast off from the second launch pad at 9.23 am on July 12. The timing has been fixed to ensure that this remote sensing satellite passes over India in well sunlit conditions so that we get quality images and pictures from its panchromatic camera,” he said.
According to Mr Satish, the entire launch vehicle was put into a threadbare analysis and anomalies rectified. Four more satellites will ride piggyback onboard PSLV-C15.
“ALSAT-2A, an Algerian satellite, two nano satellites, NLS 6.1 and NLS 6.2, from University of Toronto, Canada, and Studsat, a satellite built by students from two engineering colleges in Karnataka and Andhra Pradesh, are the satellites which will also be launched,” he said.

Prem Kumar · Post by **Prem Kumar** » 04 Jul 2010 23:00

SSSalvi: thanks for the update. Eagerly looking forward to the launch.

Regarding your earlier comment: thanks for the insights regarding practical hurdles of high res imaging. I have a couple of questions for you:

a) Do you mean that, even though we have the technical & signal processing knowledge for high res imaging, we lack in the area of space-quality CCD cameras? Could this be the reason why we seem somewhat stuck at the 0.8 - 1m resolution level. Not that this resolution is bad, but we seem to be at this limit for over a decade now

b) I read that Cartosat 2B has an advanced agile steering (up to 45 degrees). Is this related to your step-and-stare comment - i.e. Cartosat 2B is better than its predecessors in this regard? Are you aware of the other improvements in 2B versus 2A or 2?

c) An armchair newbie question: is it technically possible to have 2 cameras - one of which does the wide area, while the other one does the step-and-stare, so that we can get the best of both worlds simultaneously? Or is it easier to have say Cartosat 2A provide a wide area image & if there are specific areas of interest, the command is sent to 2B to do a high resolution strip map? Also, it is interesting to note that Cartosat-1 had 2 PAN cameras for generating 3D maps, while the Cartosat-2 series have only 1 PAN camera - any reasons for the same?

Thanks in advance

NRao · Post by **NRao** » 05 Jul 2010 02:19

if proper resources are not blocked.

Are you at liberty to mention which countries block such requests?

Also, is there a reason why India is not in this business?

TIA.

Shyam_K · Post by **Shyam_K** » 05 Jul 2010 05:28

How come this is a separate thread and not in the existing Indian space program thread?
Is BR Forum relaxing its stand on thread proliferation, if not IB4TL

SSSalvi · Post by **SSSalvi** » 05 Jul 2010 15:05

@ Premkumar

a. As mentioned in my earlier post we can change scanning parameters and get a high resolution image using the same camera system but the problem is that the area covered will be very small ( If for .8 M resolution we can image an area of 12*12 Kms .. for .4 mM resolution area covered will be 6*6 Kms ) so one has to know very accurately the exact spot which is of interest and there should be a real need for seeing the object of less than a meter ..

Can U think of any such object? Planes and Tanks can be seen with a lesser resolution also.

In order to have a better resolution a planer CCD array consisting of a rectangular arrangement of multiple CCDs ( in contrast with the linear array that is being used now ) is required .. ( something similar to current digital cameras with 12 Megapixels etc ). And that is where lies the 'control regime'.

b. I think +/- 45 deg Step and Stare ( S&S ) is common and is present in almost all crafts .. but as we try to tilt more the image distortions occur at edges and so it is rarely used to the extremes.

c. India had many missions with multiple resolution cameras working simultaneously. BUT .. they were all low resolution obtainable with fixed cameras NOT using S&S.

Unlike SPOT and other foreign satellites where the camera was moving ( and the satellite was not tilted ) to get S&S .. the Indian satellites steer the whole satellite for S&S and so naturally it is not possible to use multiple cameras looking at different areas simultaneously .. hence only one camera and no stereo images.

Pranav · Post by **Pranav** » 05 Jul 2010 18:28

SSSalvi ji, It would be good to know what is the status of SAR development in India. As far as I know SAR is mainly a matter of signal processing software, so hardware would not be the limitation.

Prem Kumar · Post by **Prem Kumar** » 05 Jul 2010 22:18

Thanks very much Salvi-ji.

Is the planar array technology something that ISRO is trying to build in-house capability in?

Very interesting to note the difference between how we do S&S versus others. Its a nuance that many of us are not aware of.

However, the following is a quote from Wikipedia on Cartosat-1, which had 2 Panchromatic cameras. Let me know if the info there needs to be corrected (or if I am reading it wrong):

Cartosat-1 carries two state-of-the-art panchromatic (PAN) cameras that take black and white stereoscopic pictures of the earth in the visible region of the electromagnetic spectrum. The swath covered by these high resolution PAN cameras is 30 km and their spatial resolution is 2.5 metres. The cameras are mounted on the satellite in such a way that near simultaneous imaging of the same area from two different angles is possible. This facilitates the generation of accurate three-dimensional maps. The cameras are steerable across the direction of the satellite's movement to facilitate the imaging of an area more frequently.

The bolded part seems to indicate that 3-d images can be taken (& digital elevation models constructed) by an appropriate positioning of 2 cameras. This is useful for surveillance too. Do you know why this approach was not continued for the Cartosat-2 series?

Also, the last sentence above seems to indicate that an independent steering of the cameras is possible - is this correct?

Regarding lower resolutions, they always provide more options dont they? Examples: it can be used in counter-insurgency for people moving in small groups. Identifying friend or foe. Also lets say, in the Pune bomb blast, a before & after picture can help identify anything out of the ordinary - like identifying a parked vehicle that might have been used by the perp.

SSSalvi · Post by **SSSalvi** » 06 Jul 2010 10:27

@ PremKumar

The 2 cameras are mounted so that one looks straight ahead of satellite while the other looks straight in the back. ( Called AFT and FORE looking cameras ). Therefore AFT will see the scene first and then as the satellite moves ahead same scene will seen by FORE camera.

It is therefore possible to view the same area from both the cameras albeit with a small difference in timing of a few seconds.

@ Pranav

Whole Technology for SAR from fabrication to application must have been known in the required forums. But SAR satellite applications are limited and the usage is not as popular as optical sensors. Of course their ability to penetrate ice and water and precision height determination is not possible in optical domain.

But large Bandwith requirements bring in certain restrictions in civilized operation.

vic · Post by **vic** » 08 Jul 2010 13:08

Re Salvi

Can you add something about the status of RISAT-1 and future of our Cartostats series?

Also with telecom satellites getting heavier & reaching around 6 tons, will the GSLV series be able to keep up?

Varoon Shekhar · Post by **Varoon Shekhar** » 08 Jul 2010 18:56

The PSLV Cartosat 2B mission is now being previewed on the Isro website!

http://isro.org/pslv-c15/pdf/CARTOSAT-2B-brochure.pdf

SSSalvi · Post by **SSSalvi** » 11 Jul 2010 16:29

The final 50-and-a-half-hour countdown for the launch of the Polar Satellite Launch Vehicle (PSLV) began at 6.52am on Saturday. The 230-tonne 44.4-metre tall four-stage rocket, PSLV-C15, carrying five satellites is slated for lift off at 9.22am on Monday from Sriharikota.

http://timesofindia.indiatimes.com/city ... 152897.cms

The five satellites are: indigenous 694kg Cartosat-2B, 116kg Alsat 2A of Algeria, 6.5kg Aissat built by Space Flight Laboratory of University of Toronto, one kg Tissat-1 of University of Applied Sciences, Switzerland and Studsat weighing less than one kg designed and developed by 45 students from seven engineering colleges of Bangalore and Hyderabad.

Sanjay M · Post by **Sanjay M** » 12 Jul 2010 05:50

Hey people, I'm waiting to see this thing go up - anybody got any links to a live webcast?

Usually the ISRO ones are crappy, so does anybody know of a good streaming site?

Sanjay M · Post by **Sanjay M** » 12 Jul 2010 08:24

Anyway, here are the links to live news streaming broadcasts from CNN-IBN and NDTV. Hopefully, they'll feature some coverage of the launch, which should happen shortly.

CNN-IBN:

http://ibnlive.in.com/livestreaming/CNN-IBN/

NDTV:

http://www.ndtv.com/news/videos/video_l ... x7&live=tv

SSridhar · Post by **SSridhar** » 12 Jul 2010 08:48

Live telecast on DD National.

Automatic launch sequencer has taken over at launch-12 minutes

Sanjay M · Post by **Sanjay M** » 12 Jul 2010 08:57

I can't even connect to DD over internet.

Anybody have a good link?

marimuthu · Post by **marimuthu** » 12 Jul 2010 08:59

30 Sec to go

marimuthu · Post by **marimuthu** » 12 Jul 2010 09:00

Successful Takeoff.

dinesha · Post by **dinesha** » 12 Jul 2010 09:01

Lift off Normal

marimuthu · Post by **marimuthu** » 12 Jul 2010 09:02

First Stage Separated.Second stage Ignited

marimuthu · Post by **marimuthu** » 12 Jul 2010 09:03

Heat Shield separated

rahuls · Post by **rahuls** » 12 Jul 2010 09:04

why don't they allow private TV channels for live broadcast. The DD liftoff shots were extremely poor.

marimuthu · Post by **marimuthu** » 12 Jul 2010 09:05

Second Stage Separated. Third Stage Ignited

rahuls · Post by **rahuls** » 12 Jul 2010 09:05

ps 3 ignition

marimuthu · Post by **marimuthu** » 12 Jul 2010 09:09

Third Stage Separated. Fourth Stage Ignited

kvraghavaiah · Post by **kvraghavaiah** » 12 Jul 2010 09:12

Marimuthu and Rahuls,
Thank you for your updates. Your posts are the only live source for me.