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Forum:Satellites - Robotic Probes
Topic:InSight to Mars: Viewing, questions, comments
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BlackarrowSeriously? Sixth lander in a row which ISN'T designed to look for signs of life? This one even seems to have the ability to dig down a respectable distance to escape the ultraviolet "death zone." To use what I believe to be the American vernacular: "Way to skirt around the big question!"
Robert PearlmanMy guess, and it's just that, is that the tools needed to definitively answer the life question are too expensive to fit within a cost-capped Discovery-class mission.

On edit: To put the budget into some perspective, per NASA, the InSight mission cannot afford to fly a color camera, if only for outreach reasons. The lander will only have two black and white engineering cameras, similar in resolution quality and field of view to Spirit's and Opportunity's NavCam and HazCam.

Fra MauroInteresting choice. I like the mission but I wonder if one reason it was chosen was to quell the critics that the Administration is shutting down the Mars program. Do we know which choices lost out? It's been awhile since we have been to Venus.
Robert PearlmanAs the press release notes:
The other two proposals were for missions to a comet and Saturn's moon Titan.
Specifically, the missions were Comet Hopper (CHopper), which would have studied the evolution of 46P/Wirtanen by landing on the comet multiple times and observing its changes as it interacts with the sun, and Titan Mare Explorer (TiME), which would have provided the first direct exploration of an ocean environment beyond Earth by landing in, and floating on, a large methane-ethane sea on Saturn's moon Titan.

John Grunsfeld said yesterday that InSight was chosen over the other two because it was thought to have the best chance of keeping to the $425 million budget and making its launch date in 2016.

BlackarrowI'm going to make a prediction: it will get a colour camera. NASA has learnt its PR lessons.
Originally posted by Blackarrow:
I'm going to make a prediction: it will get a colour camera. NASA has learnt its PR lessons.
Well, for the general public, InSight won't have much of an impact, color pics or not. Most people will just think "yet ANOTHER one to Mars? Stop wasting my taxes".

I think TiME was a much better choice. Far more PR impact for average Joe for about the same cost (alien oceans!!!), while having the benefit of keeping research into Titan alive. InSight could have flown later in this decade and no one would loose anything, while the window of opportunity for Titan for about US500 million is now lost for next 20 years or so.

Anyway, don't want to hijack this thread for ranting.

Originally posted by Gorgon:
InSight could have flown later in this decade and no one would lose anything, while the window of opportunity for Titan for about US500 million is now lost for next 20 years or so.
Why? Something to do with orbital mechanics?
GorgonIn a way, yes. The thing is that if we launched in the present time window TiME would not need a data relay orbiter because it would be able to communicate directly with Earth for a few hours. It would be a short mission like Huygens but it would be within US500 million. If we launch it in the next 20 years or so we could make it last for years but we would need the orbiter, making it 2 or 3 times more expensive. This last option means great science but it also means that we probably will never see it fly, given NASA's "obsession" with Mars right now and the significantly higher budget needed.

InSight is a great mission with great scientific interest, no doubt, but it could have been flown at any time we want for the same price, thus in my opinion it was the wrong decision.

You can more details here (it's a really nice blog, by the way).

Robert PearlmanDan Leone with SpaceNews is reporting that InSight won't be launching in 2016:
NASA's InSight won't launch in March as planned due to a problem with a CNES-built instrument. More after a 3:30 p.m. EST presser.
On Dec. 4, NASA reported that the vacuum container carrying the main sensors for CNES' Seismic Experiment for Interior Structure (SEIS) was leaking.

A delay would push InSight's launch out to 2018 for favorable Earth-Mars geometry.

Robert PearlmanPeter B. de Selding with SpaceNews followed up with CNES president Jean-Yves Le Gall:
We're not giving up resolving NASA Mars InSight lander instrument leak; we have till 5 January to nail it down.

We're not 100% sure that the leak [in] Mars InSight SEIS instrument isn't [a] leak-measure issue rather than actual leak. We took three InSight SEIS leak measures, all with identical results. That's odd if it's a real leak; could be false positive.

Robert PearlmanNASA confirmed the delay:
After thorough examination, NASA managers have decided to suspend the planned March 2016 launch of the Interior Exploration using Seismic Investigations Geodesy and Heat Transport (InSight) mission. The decision follows unsuccessful attempts to repair a leak in a section of the prime instrument in the science payload.
HeadshotWho made the decision to farm out the SIES to CNES? NASA, JPL, or Lockheed Martin?
Robert PearlmanIt wasn't farmed out; CNES's involvement was part of the original proposal for the mission. CNES and its partners are providing SEIS because the French have been leaders in the development of highly-sensitive seismometers. To quote John Grunsfeld:
Our partners at the French space agency are some of the world's experts in this technology.
SEIS is a cutting-edge science instrument that has benefited from years of research by the French. As NASA's Jim Green explains:
This is a design that has been developed over about two decades in France. It's a very complex and very difficult system to design and build.
And to be clear, the instrument itself works. It is only the titanium case (sphere) that surrounds the sensors and holds the vacuum that is the problem. Again, Green:
The sensors themselves, electronics, all of the systems of this instrument performed flawlessly in the testing. The problem has been in this vacuum enclosure.

It is not that exotic of a technology to maintain a vacuum. The difficulty comes in being able to build a vacuum system that can maintain its integrity with the very harsh conditions on Mars — the very cold temperatures, the survival of the vibrations from the launch and the landing.

HeadshotThe problem I am having is that someone dropped the ball on a relatively simple issue and now the entire mission is in jeopardy.

While the seismometer itself apparently works properly, as Robert wrote, to produce meaningful results it must be contained in a vacuumized container. Manufacturing such a container should NOT require cutting edge technology. Yet the damn thing cannot maintain a vacuum.

This is not in the same league as the reasons behind the JWST or MSL launch delays, yet it has placed the InSight mission in jeopardy. During the next two years or so the spacecraft will be in storage, subject to outright cancellation due to mounting budgetary issues. The issue is not just storing the spacecraft for two years while maintaining its support work force. What about the launch vehicle? Will that be in storage as well? If not, will NASA have to purchase a new vehicle at 2018 prices or will they revert back to 2016 prices? We are getting close to InSight's fiscal ceiling and NASA pointedly did NOT promise that the mission won't be cancelled outright. After all, now we have the issue of a new president during this delay. He or she could easily terminate the whole mission on a whim.

It would have been far more difficult to do something like that if InSight had been launched on schedule and was working on the surface of Mars.

Robert PearlmanI think you're still underestimating the challenge that the vacuum sphere presents. To quote Bruce Banerdt, InSight's principal investigator, at JPL:
The vacuum we're maintaining inside the sphere varies. At the very beginning of life, when we first pump it down, it's at about 10^-7 millibars, so that's like less than a billionth of the pressure of the Earth's atmosphere.

From just normal kind of out-gassing of materials inside the sphere, we expect it to raise up a little bit, maybe a thousandth of a millibar and we can operate our seismometers at about a tenth of a millibar, which is again, about a thousandth of the pressure of the Earth's atmosphere.

The leak rate that we were seeing was bringing it up from essentially zero to about two-tenths of a millibar over the course of a few days. So even today, we still have less than a ten-thousandth atmosphere of pressure in there, which is by most standards, a pretty darn good vacuum, but for our purposes we need a better vacuum than that.

The eight to nine inch sphere has welds, as well as ports used to draw the vacuum and to connect the device to the spacecraft. The welds have been re-welded and the connections have been checked and re-checked (addressing earlier leaks) and they still haven't been able to identify the source of the current leak.

The way NASA and CNES described it, it does not sound like someone "dropped the ball" but that it is just a very difficult piece of hardware to perfect, and that the current leak was only discovered very recently.

As for the launch vehicle, NASA's Jim Green said that the agency still needed to get with United Launch Alliance to work out the situation.

SpaceAholicThe question is why poor vacuum integrity was not fully detected until close to launch. That speaks more to an issue with test/evaluation methodology.
Robert PearlmanThe sphere was sealed for flight earlier this year, which is when the first of the leaks was discovered and addressed.

The later leaks, including the current one, were found during the final environmental tests in France before SEIS was set to ship to the United States for integration with InSight.

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