Chandrayan-2 Mission
Re: Chandrayan-2 Mission
So what is next? Would this mission be abandoned and would they have to start a new one or is this salvageable?
Re: Chandrayan-2 Mission
Too big a mistake...SaiK wrote:Typo. Sorry
Can't be forgiven onlee...
Re: Chandrayan-2 Mission
Just a reminder to all here: that on its way to put this lander down on the moon, India did put its second space craft on the orbit of the moon. Chandrayaan-2 will be doing science for next year or longer. (Lander would have lasted about 2 weeks only).
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Re: Chandrayan-2 Mission
Budget has to be sanctioned for a Chandrayaan 3. That should be a question for the government.
Re: Chandrayan-2 Mission
Vikram cannot communicate to ground station. It can only talk to Orbiter. If the Orbiter is on the other end, can Vikram communicate to it? Don't we need to wait for it circle back.
Re: Chandrayan-2 Mission
The orbiter mission is on for atleast one year.KJo wrote:So what is next? Would this mission be abandoned and would they have to start a new one or is this salvageable?
They will complete that detailed 3D map of the Moon, that was interrupted when Chandrayaan 1 stopped functioning.
India should have the MOST high resolution image + 3D map of the moon by the time this mission ends
Re: Chandrayan-2 Mission
It can communicate directlyDasari wrote:Vikram cannot communicate to ground station. It can only talk to Orbiter. If the Orbiter is on the other end, can Vikram communicate to it? Don't we need to wait for it circle back.
Pragyan rover, can only communicate with Vikram Lander, which communicates with the Deep Space Network
Re: Chandrayan-2 Mission
If ISRO has backup rover and lander then we can attempt one more in near future.
ISRO has landed another made in India unit on moon. Congrats. Keep going. You never walk alone.
ISRO has landed another made in India unit on moon. Congrats. Keep going. You never walk alone.
Re: Chandrayan-2 Mission
Loss of attitude control is the most probable cause.shaun wrote:Why communication went off at 2.1 km altitude ?? An explosion ??
Re: Chandrayan-2 Mission
Is Vikram able to communicate with the orbiter? Does that mean that the lander is still intact?
Re: Chandrayan-2 Mission
If it is confirmed failure then I think ISRO should go for a Lander + Rover only mission with a Vikram-R modified accordingly with in the next year
Re: Chandrayan-2 Mission
The camera on the Orbiter looks HUGE !!!!
It is like a mini hubble telescope no?
If it is Hi-Res enough, it can see ALL the moon missions.
The only hitch is that the Vikram Landing site have sunlight for pictures to be available !
It is like a mini hubble telescope no?
If it is Hi-Res enough, it can see ALL the moon missions.
The only hitch is that the Vikram Landing site have sunlight for pictures to be available !
Re: Chandrayan-2 Mission
MCDC/ test test test.. landing on Earth as many times with actual test vehicle. Not scaled down versions.
Just saying. It is expensive
Just saying. It is expensive
Re: Chandrayan-2 Mission
It depends on what it communicated. Health check should reveal.Dilbu wrote:Is Vikram able to communicate with the orbiter? Does that mean that the lander is still intact?
Re: Chandrayan-2 Mission
If there is no orbiter, then they can land a much bigger lander, with way more equipment on it.Kakarat wrote:If it is confirmed failure then I think ISRO should go for a Lander + Rover only mission with a Vikram-R modified accordingly with in the next year
Maybe they can have the Rover go back and forth between the lander, charge, stay warm, transmit its data, then go out again once the sun rises
Re: Chandrayan-2 Mission
Space is hard and unforgiving. I hope if ISRO needs money then it will be made available.SaiK wrote:MCDC/ test test test.. landing on Earth as many times with actual test vehicle. Not scaled down versions.
Just saying. It is expensive
Re: Chandrayan-2 Mission
This is Mission Control Centre. #VikramLander descent was as planned and normal performance was observed up to an altitude of 2.1 km. Subsequently, communication from Lander to the ground stations was lost. Data is being analyzed.
#ISRO
#ISRO
Re: Chandrayan-2 Mission
They haven't mentioned yet that the lander crashed !!
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Re: Chandrayan-2 Mission
Moon’s gravity is 1/6 of the earth, then there is no atmosphere as it is a virtual vacuum. No way to test for that on earth. However, it seems ISRO has not mastered 3-axis stabilization control under the influence of less gravity. To do this experiments may have to be carried out in orbit.SaiK wrote:MCDC/ test test test.. landing on Earth as many times with actual test vehicle. Not scaled down versions.
Just saying. It is expensive
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Re: Chandrayan-2 Mission
It was coming down faster than 200 kmph. Vikram is in pieces.shaun wrote:They haven't mentioned yet that the lander crashed !!
Re: Chandrayan-2 Mission
We still don't know what happened after 2.1 km , with no communication from the lander
Re: Chandrayan-2 Mission
To fail is to succeed.
I thank the fine folks at ISRO to dare and dream and persist in the face of failure. The entire nation is with you, ISRO. We are rooting for you folks to try again!!
I thank the fine folks at ISRO to dare and dream and persist in the face of failure. The entire nation is with you, ISRO. We are rooting for you folks to try again!!
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Re: Chandrayan-2 Mission
Chandrayaan 3 is the need now. The PM should have said he will try for that.
Re: Chandrayan-2 Mission
It seems we have a precedent
Surveyor 4 was the fourth lunar lander in the American uncrewed Surveyor program sent to explore the surface of the Moon. This spacecraft crashed after an otherwise flawless mission; telemetry contact was lost 2.5 minutes before touchdown.
Surveyor 4 was the fourth lunar lander in the American uncrewed Surveyor program sent to explore the surface of the Moon. This spacecraft crashed after an otherwise flawless mission; telemetry contact was lost 2.5 minutes before touchdown.
Re: Chandrayan-2 Mission
Why not? You just need something which exerts a vertical upward force of 5/6 times that of weight of the lander. For example, in a tethered experiment, you can use a helium balloon.Mort Walker wrote:Moon’s gravity is 1/6 of the earth, then there is no atmosphere as it is a virtual vacuum. No way to test for that on earth. However, it seems ISRO has not mastered 3-axis stabilization control under the influence of less gravity. To do this experiments may have to be carried out in orbit.SaiK wrote:MCDC/ test test test.. landing on Earth as many times with actual test vehicle. Not scaled down versions.
Just saying. It is expensive
Re: Chandrayan-2 Mission
Sources confirm that up to 2.1 km all was fine. Soon rotation rates increased and the engine thrust went up to 100% in place of around 70%. The velocity too shot up indicating tumbling & crashing. At this stage, the telemetry link was lost. https://twitter.com/writetake/status/11 ... 28256?s=20
Re: Chandrayan-2 Mission
I have not failed. I've just found 10,000 ways that won't work.hgupta wrote:To fail is to succeed.
I thank the fine folks at ISRO to dare and dream and persist in the face of failure. The entire nation is with you, ISRO. We are rooting for you folks to try again!!
Thomas A. Edison
The real success of the mission is in the awareness and spark that it will kindle in a million young minds who will build the future iteration of ISRO and India. It has already succeeded in that.
Re: Chandrayan-2 Mission
Does this mean, we'll get the data already transmitted to the orbiter as well as pics in approx 2 hrs when the lander is also in line with the earth? Perhaps from other telemetry stations?
Re: Chandrayan-2 Mission
Sorry meant orbiter...
Re: Chandrayan-2 Mission
The final moments of Vikram Lander:
The graph deviates at 2:17 seconds. At 2:42, Vikram is nearly inverted !!! It recovers, then over corrects !!!
It tumbled at the critical juncture when soft landing phase was started. This indicates perhaps that one engine shut off later than the other, causing an imbalance.
The graph deviates at 2:17 seconds. At 2:42, Vikram is nearly inverted !!! It recovers, then over corrects !!!
It tumbled at the critical juncture when soft landing phase was started. This indicates perhaps that one engine shut off later than the other, causing an imbalance.
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Re: Chandrayan-2 Mission
What causes engine throttling at 100%. The control logic was probably fine, but hardware was not.
Re: Chandrayan-2 Mission
ISRO already has the pics.Najunamar wrote:Does this mean, we'll get the data already transmitted to the orbiter as well as pics in approx 2 hrs when the lander is also in line with the earth? Perhaps from other telemetry stations?
Remember, the orbits were adjusted to have the orbiter be insight of the lander to observe the landing.
Re: Chandrayan-2 Mission
See from 2:42 till 2:59 ...
Re: Chandrayan-2 Mission
Trusting my eyesight and memory, the last I saw the telemetry data from the screen :
Horizontal velocity 48.1 m/s
Vertical velocity 59.8 m/s
Downrange distance: 1.09 km
Earth communication: OFF
Horizontal velocity 48.1 m/s
Vertical velocity 59.8 m/s
Downrange distance: 1.09 km
Earth communication: OFF
Re: Chandrayan-2 Mission
That's exactly what I recollect.Amber G. wrote:Trusting my eyesight and memory, the last I saw the telemetry data from the screen :
Horizontal velocity 48.1 m/s
Vertical velocity 59.8 m/s
Downrange distance: 1.09 km
Earth communication: OFF
Re: Chandrayan-2 Mission
If it was inverted or horizontal, and its engines burning, that will cause deviation from the flight path laterally, which possibly seems to have happened.
Also descent velocity which was coming down, will start to now increase
Also descent velocity which was coming down, will start to now increase
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Re: Chandrayan-2 Mission
The balloon will exert a vertical force which is not at the center of mass of the lander.Indranil wrote:Why not? You just need something which exerts a vertical upward force of 5/6 times that of weight of the lander. For example, in a tethered experiment, you can use a helium balloon.Mort Walker wrote:
Moon’s gravity is 1/6 of the earth, then there is no atmosphere as it is a virtual vacuum. No way to test for that on earth. However, it seems ISRO has not mastered 3-axis stabilization control under the influence of less gravity. To do this experiments may have to be carried out in orbit.
Re: Chandrayan-2 Mission
Helium balloons will not work in vacuum as the way you think.. it will only increase the weight of the lander (+ mass of helium)..Indranil wrote:Why not? You just need something which exerts a vertical upward force of 5/6 times that of weight of the lander. For example, in a tethered experiment, you can use a helium balloon.Mort Walker wrote:
Moon’s gravity is 1/6 of the earth, then there is no atmosphere as it is a virtual vacuum. No way to test for that on earth. However, it seems ISRO has not mastered 3-axis stabilization control under the influence of less gravity. To do this experiments may have to be carried out in orbit.
(There is NO practical way we know to simulate low gravity except going in earth's orbit (or vomit-comet type rides which are essentially the same).
(Swimming is water may make you feel "weightless" but it is not exactly what you need to simulate zero g, for obvious reasons)
Last edited by Amber G. on 07 Sep 2019 04:09, edited 1 time in total.
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Re: Chandrayan-2 Mission
^^^He's talking about doing it on earth. Then there is the question of wind too.