Author
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Topic: Apollo 9 LM-3 'Spider' Earth re-entry
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Paul78zephyr Member Posts: 735 From: Hudson, MA Registered: Jul 2005
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posted 11-26-2017 11:54 AM
I have read that the ascent stage of Apollo 9's lunar module LM-3 "Spider" remained in Earth orbit until 1981 (about 12 years). Why was it not commanded to have a safe controlled re-entry at the end of the mission as opposed to an uncontrolled re-entry? |
randy Member Posts: 2518 From: West Jordan, Utah USA Registered: Dec 1999
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posted 11-26-2017 11:59 AM
That's a good question, one which I've never thought of. I too would like to know. |
Rusty53 Member Posts: 50 From: Rochester, NY USA Registered: Jun 2010
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posted 11-26-2017 09:01 PM
According to NASA Technical Note D-7949 a Lunar Module Mission Programmer (LMP)... ...was designed to enable the lunar module to meet the requirements for unmanned near-Earth orbiting missions and to be adaptable to restricted unmanned lunar landing missions. It was utilized on the unmanned Apollo 5 LM and the Apollo 9 and 10 LMs to certify its function. |
Grounded! Member Posts: 473 From: Bennington, Vermont, USA Registered: Feb 2011
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posted 11-27-2017 12:13 AM
It's a good question. Was there a reason to keep it in orbit? Was there additional data to be obtained? There was not as much of a "space junk" issue back then as there is now. It would certainty have been easy to de-orbit the assent stage at that time if so desired. |
oly Member Posts: 1323 From: Perth, Western Australia Registered: Apr 2015
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posted 11-27-2017 12:43 AM
From memory, I believe I have previously read that following the test flight and undocking the LM ascent engine was test fired again until fuel exhaustion in an attempt to test the engine performance; the fuel system, including low fuel warnings, etc; the remote telemetry system and the performance of the batteries. I guess that they wanted it to fly for as long as possible to gain as much data as possible. |
Solarplexus Member Posts: 120 From: Norway Registered: Jan 2014
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posted 11-27-2017 09:32 AM
Could they have used a space shuttle that had delivered its cargo to retrieve it and returned it safely to earth? |
Robert Pearlman Editor Posts: 47542 From: Houston, TX Registered: Nov 1999
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posted 11-27-2017 10:00 AM
LM-3 re-entered the atmosphere on Oct. 23, 1981, about three weeks shy of the launch of the second space shuttle mission, STS-2. The 10-foot, 7-inch tall by 13-foot, 10-inch wide ascent stage may have fit into the payload bay, but at that point in the program, without any EVA experience or use of the Canadarm robotic arm, it would have been challenging, to say the least. And making it even more unlikely would have been the lack of any capture points on the ascent stage, the need for a custom mount to hold the stage securely in the payload bay, the dangers associated with any residual propellant in the ascent stage tanks, and other logistical hurdles. |
Rusty53 Member Posts: 50 From: Rochester, NY USA Registered: Jun 2010
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posted 11-27-2017 10:37 PM
As per my previous post, perhaps the reason Spider was placed in a high elliptical orbit was because NASA wanted to certify the LMP system which allowed the ascent engine to be fired when unmanned. Interesting that the only other manned LM to have a LMP system (A10 Snoopy) was also burned to oxidizer depletion making it the only LM placed into a solar orbit. |
p51 Member Posts: 1736 From: Olympia, WA Registered: Sep 2011
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posted 11-27-2017 11:59 AM
quote: Originally posted by Solarplexus: Could they have used a space shuttle that had delivered its cargo to retrieve it and returned it safely to earth?
Even if Columbia was up and running before the orbit decayed, I can't imagine NASA capturing this and bringing it back. |
Solarplexus Member Posts: 120 From: Norway Registered: Jan 2014
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posted 11-27-2017 12:15 PM
I agree in that. Safety first. In theory it would be possible according to Robert but hardly in reality. |
Paul78zephyr Member Posts: 735 From: Hudson, MA Registered: Jul 2005
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posted 11-27-2017 12:40 PM
quote: Originally posted by Robert Pearlman: LM-3 re-entered the atmosphere on Oct. 23, 1981
Is there any documentation which states what its final orbit was and where it came down? |
MartinAir Member Posts: 130 From: Registered: Oct 2020
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posted 12-07-2021 10:18 AM
Is it known where the ascent stage "landed"? Were any fragments recovered? |
Space Cadet Carl Member Posts: 274 From: Lake Orion, MI Registered: Feb 2006
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posted 12-13-2021 09:04 AM
There's a few mentions online about LM-3's descent stage reentry into the Indian Ocean near North Africa on March 22nd, 1969. But there doesn't seem to be any indication of exactly where the ascent stage reentered on October 23rd, 1981. |