Chandrayaan-2 : Updates

Comms cut off at 1.8 km does not indicate crash
Rather it indicates possible component failure where higher than anticipated g force and assorted stress and strain must have effected the comms

1.8km above the landing site not the ground. we were landing inside the crater and the graph showed sudden drop in altitude and speed. It's a clear indication that it has hit the rim of the crater or engine explosion.
 
Ouch:(. The orbiter was always the main part of the mission with the lander and rover being the icing and cherry on the mission's proverbial cake (the rover for instance was only designed to operate during the lunar day and for one lunar rotation, approximately 14 earth days). Hopefully nothing untoward happened to the lander and it just lost comms like China's Yutu rover and can be located and recovered.

...

On a tangent, when the mission was still in launch phase and the initial launch was scrubbed due to anomalous activity there was postulation that it could have been interference from American satellites, for whatever rational people could come up with. Here's a great look at why that simply couldn't have been the case, as I rightfully pointed out in this same thread. The original thought:

Chandrayaan-2 : Updates

Amateur sleuths managed to track down the satellite, USA 224 - a US National Reconnaissance Office KH-11 recon satellite - which took pictures of Iran's failed rocket launch several weeks ago and which Trump declassified. Using shadows in the picture, sleuths where able to reverse engineer the likely candidate satellite based on its orbit and known location at the time. Another reminder that nothing in space stays secret as someone's always watching.

Sleuths Find the Top-Secret (and Classified) Satellite Behind Trump's Tweeted Photo

Space is just hard. It's literally rocket science and sometimes things go wrong. Pick yourself up, press forward and continue on apace. No omelet is made without a few broken eggs along the way.
 
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The orbiter was always the main part of the mission with the lander and rover being the icing and cherry on the mission's proverbial cake


That's BS

the main part was the landing. You don't spend f*cking millions just to put cherry on Top. We wanting to soft land on moon and send our rover to tell the world that we have a reliable tech now to reach on the moon.

You can send millions of orbiters, that's not a big deal for ISRO now.

Lets either be positive and wait for the signals or accept it as failure for next success.
 
1.8 km above the landing zone and deviated means critical component failure.graph showed high speed after failure.i think it was probably destroyed.anyway great achievement.i have seen many people on both sides who discussed this topic to lock each other.i think all those people need medical attention.our rivalry is a different topic and scientific achievements is totally different topic.i was reading a book from indian author and it was amazing.knowledge shouldn't be used to lock each other.landing is always difficult.may be India will achieve this goal next year.
 
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That's BS

the main part was the landing. You don't spend f*cking millions just to put cherry on Top. We wanting to soft land on moon and send our rover to tell the world that we have a reliable tech now to reach on the moon.

You can send millions of orbiters, that's not a big deal for ISRO now.

Lets either be positive and wait for the signals or accept it as failure for next success.
Landing is the hardest part.you should not discourage them.learning is a continuous procedure.
 
Lots of questions to ponder over

It could be a malfunction with the solenoid valves for fuel flow in the thursters. They work in vacuum and under earth's gravity, but how does it work in moon's gravity which is 1/6th of earth's and has several dense gravitational spots, weak magnetic field and surrounded by atomically charged particles in vacuum?

Also, the landing region which is close to the S-pole of moon is unexplored. Recently Israel's lander also failed in the same region. Is there an anomaly in moon's gravity and/or magnetic field close to its pole area causing confusion in determining the right orientation for the Lander. What if the orientation turned 180 degrees inverted, so instead of applying brakes on descent, the thursters will propel the Lander with high acceleration towards the moon's surface.

What kind of a gyroscope did it use for orientation determination?

Also, ISRO should have mounted four telescopic expandable/collapsible antennas extending in four directions at 45 deg inclined to the vertical, on the tip of which they could have mounted some balancing and orienting sensors, along with video cameras with signals beaming back to earth via Orbiter in real time.

What about the battery? Is it possible that the battery drained out doing several trajectory maneuvers during descent? Did it have a separate battery pack for communication and separate for maneuvers?
 
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1.8 km above the landing zone and deviated means critical component failure.graph showed high speed after failure.i think it was probably destroyed.anyway great achievement.i have seen many people on both sides who discussed this topic to lock each other.i think all those people need medical attention.our rivalry is a different topic and scientific achievements is totally different topic.i was reading a book from indian author and it was amazing.knowledge shouldn't be used to lock each other.landing is always difficult.may be India will achieve this goal next year.

That entire phase is artificial intelligence powered autonomous landing. Any number of things could have gotten wrong.
 
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Lol f*ck all this

Give ISRO another 50 million dollars and get them to build a modified lander / rover only and have them sent it by 1 years time . No need of orbiter since the current one is functional and will support the same.

The built time will also be considerably reduced due to obvious reasons.

A PSLV should be able to launch it.
 
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Lol f*ck all this

Give ISRO another 50 million dollars and get them to build a modified lander / rover only and have them sent it by 1 years time . No need of orbiter since the current one is functional and will support the same.

The built time will also be considerably reduced due to obvious reasons.

A PSLV should be able to launch it.
I was thinking the same. We can make orbiters, but landers need more practice. Make a small lander and call it a TD mission.
 
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Things look little different ... they don't add up .... here the altitude shown is 1.334 kms

1567829037263.png

And the graph shows like this which seems a bit on the higher side and is about 1.5 km off the landing point

1567829182570.png

And this is the last signal ISRO got. Here you can see the altitude is not more than 400 m and is about 1 km off the mark from the intended landing point. At this time the blip moved slow to the right, which means that the Lander was maneuvering slow to its intended landing point. Looks like the hovering part and scanning for a site to land did not work, instead it may have fallen down in a free fall from 1/2 km height. Or it may have hit a hill while moving sideways. ISRO need to add 360 degree sensor so that it's movement is safely decided. Now ISRO will turn on their terrain mapping cameras on the Orbiter to establish what terrain was around in that area. So close and missed towards the end. SAD indeed ....

1567829663542.png
 
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