Chandrayaan 1, India's First Lunar Probe Options

[Guest_Zvezdichko_*]

http://www.siasat.com/english/news/efforts...ink-chandrayaan

India is trying to restore link with Chandrayaan-1, but the chances are slim.

[Hungry4info]

I don't suppose they could have LRO try to send it commands?

[Greg Hullender]

I don't suppose they could have LRO try to send it commands?

Why do you think that would help? I'd be surprised if it were possible at all, given incompatibilities between the two craft, but why do you think a signal from LRO might work when a much stronger signal from Earth did not?

--Greg

[djellison]

Quite. LRO can't help in that regard. It might be possible for LRO to image Chanrdrayaan 1 in the MGS->MODY style perhaps. Check it's still there and hasn't gone 'poof'.

Doug

[nprev]

Interesting thought, if they ever get close enough to each other for that to be attempted. Would they even try that during LRO's prime mission, though? I'm sure it would require off-nadir pointing & possibly slewing during the shot, and therefore propellant expenditure.

[Guest_Zvezdichko_*]

PS: It also wouldn't hurt if ISRO learn some better PR too!

Agreed!

I felt a little saddened about the loss of Chandrayaan-1, but that was all I felt. I was never emotionally connected to the mission.

In contrast, the loss of Phoenix was a teary moment for me. I believe that the contact with the mission will be restored despite the fact I realise the chances will be very, very slim. I try not to think that Spirit and Oppy will die some day too.It will be one of the saddest days of my life.

[Hungry4info]

Why do you think that would help? I'd be surprised if it were possible at all, given incompatibilities between the two craft, but why do you think a signal from LRO might work when a much stronger signal from Earth did not?

Perhaps Chandrayaan-1 had an issue with its star-tracker or something, and although functional, isn't orientated in such a way to allow communications with Earth. Having LRO try to transmit would increase that slight chance that Chandryaan-1 would receive a signal by there being two sources of a transmission for Chandrayaan-1's antenna to by-chance be orientated to.

I know it was a long shot.

[Bhas_From_India]

It's disappointing, but nonetheless it is a partial success and according to ISRO the mission achieved most of its science goals. For India's very first planetary exploration mission, it's been pretty successful when you consider the many failures the USA and USSR had in their early days of space exploration.

The mission has also now created a layer of invaluable expertise in India for planning, building and operating planetary exploration missions. Forward with India's space programme!

PS: It also wouldn't hurt if ISRO learn some better PR too!

There is still large % of people in india who thinks spending millions on such missions is waste and instead that can be spent on xyz problems.
this could be one reason why there is not much publicity. Hope things will improve over next missions... :-)

ISRO has a new site: http://www.isro.gov.in/ supposed to be better than the old one.


Link about failure reasons: [[ http://www.hindu.com/2009/08/31/stories/2009083157910100.htm ]]

Due to very high radiation in the atmosphere, power-supply units controlling both the computer systems on board failed, snapping the communication connectivity. Some devices were more susceptible to radiation and temperature fluctuations, which resulted in the computer power supply being cut. The kind of radiation problem faced was not anticipated, Mr. Nair said.

“We have learnt some valuable lessons, and we have to look for devices that are less susceptible to radiation in future expeditions. We have set up an assessment committee to study all aspects. The Chandrayaan-II will not be delayed.”

[Guest_Zvezdichko_*]

ISRO has a new site: http://www.isro.gov.in/ supposed to be better than the old one.

Sorry to be brutal but I don't believe it's for good. Where's the old Chandrayaan-1 gallery? The one listed on the spacecraft site (http://www.isro.org/chandrayaan/htmls/home.htm) is incomplete and the old ISRO version had several more images published there.

The new site has only several Earth images from Chandrayaan-1. The others look lost.

[Greg Hullender]

I know it was a long shot.

There's a difference between a one-in-ten longshot and the kind of longshot that makes flipping a coin twenty times in a row and getting heads every time look like a good bet.

That said, the "official" explanation that failure resulted from "very high radiation in the atmosphere" seems even sillier. The moon doesn't have any atmosphere to speak of, and it's hard to buy the idea that there's more radiation in lunar orbit than elsewhere in cislunar space. If it was that sensitive, how did it make it through the Van Allen belts?

--Greg

[Guest_Zvezdichko_*]

No, it's not something related to radioactivity. It's thermal radiation. Which basically means that the temperature in Low lunar orbit is very high. As the Lunar pioneer (lunarnetworks.blogspot.com) wrote to me yesterday - it's very hard to protect a spacecraft from this type of radiation.

[Greg Hullender]

It's thermal radiation . . . it's very hard to protect a spacecraft from this type of radiation.

So how does LRO manage it? And how did the Indian Space organization fail to know about it?

--Greg

[ugordan]

Probably boils down to inadequate modelling and/or insufficient thermal vacuum testing of the spacecraft.

[Guest_Zvezdichko_*]

Gordan is right and I'd add to this: Lack of experience with planetary spacecraft.

[nprev]

(Sigh)...The lessons that burn are the lessons we learn. There are few easy things in spaceflight.