[X] My Assistant

[atomoid]

good point, from the SEIS page:
"To avoid any vibrations transmitted through the tether from the lander (perhaps due to movement of the solar arrays when blown by the wind), damping devices have been installed.

One of the most important of these is a “relaxation” or “service” loop. A mechanical part attached to the seismometer forces the cable into a loop, which greatly reduces the potential propagation of waves from the spacecraft. This clever idea is commonly used on Earth when geophysicists deploy seismometers. Once the instrument is on the ground, it is generally recommended that the cable carrying power and data should be wound once around the seismometer’s protective cover.

Other subtle enhancements have gradually been added according to the project engineers’ inspiration. The tether, for instance, has been fitted with a small rod terminated by a small sphere allowing it to be grasped by the gripper at the end of the robotic arm. If the situation warrants it, it will therefore be possible to grab the cable on the ground and change its position.

A metal plate of roughly 300 g and fitted with prongs is also attached to the lower part of the cable; this tether prong mass will help to improve contact with the ground and prevent possible micro-movements."

[ronatu]

Looking at the deployed Seismometer on the ground, one thing occurred to me. Wouldn't the flex-cable moving around in the wind impart some minor vibrations into the instrument? Are there any isolation mechanisms on the cable interface into the instrument that will help mitigate that?

Altitude 32 km. Think about wind.

[RoverDriver]

...
One of the most important of these is a “relaxation” or “service” loop. A mechanical part attached to the seismometer forces the cable into a loop, which greatly reduces the potential propagation of waves from the spacecraft. This clever idea is commonly used on Earth when geophysicists deploy seismometers. Once the instrument is on the ground,...

This is also used by recording engineers when placing microphones on stands. Not only they put the mike on elastic suspension mounts but also add a service loop to avoid any (mechanical and electrical) noise that can be transmitted through the cable.

Paolo

[James Sorenson]

Altitude 32 km. Think about wind.

Yes, and still vibrations were made of the solar panels flapping that were detected by the instrument on the lander. Parachutes have been seen in the past blowing over in the wind. A thin and light flex cable almost surely can still move and resonate in the wind.

[Phil Stooke]

Looking at this image:

https://mars.nasa.gov/resources/22231/fores...e/?site=insight

the cable is much lower than at the present with the weighted section on the ground. Presumably we will see some changes in the cable as they optimize things.

Phil

[Pikaia]

In this image I am pretty sure that the TSB is open.

Looking at this image:

https://mars.nasa.gov/resources/22231/fores...e/?site=insight

the cable is much lower than at the present with the weighted section on the ground. Presumably we will see some changes in the cable as they optimize things.

Phil

[Pikaia]

Im assuming the Seis site may only release news in French, as the english version simply lacks a 'News' (Actualités) link.

Unfortunately we don’t have the capability to release the SEIS news in French and English, and the news section is indeed lacking in the english version of the site. I assumed that English speakers would go to the NASA/JPL websites for news.

[nprev]

Welcome to UMSF, Pikaia! We look forward to your insights about SEIS as the experiment proceeds.

Admin hat on: Fellow members, let's please remember that the InSight program, like all others, has hard constraints in time, money, and personnel; there's never enough of any of those things, so they will of course focus on accomplishing the mission above all else. They do not owe us anything whatsoever in terms of websites translated for our convenience or cookies before bedtime, for that matter. Please review the Rules and Guidelines, esp. rule 2.6.

Two posts hidden.

[Gerald]

Currently, I don't have the time to translate the whole article. But maybe of primary interest for the the next weeks, the article says, that the SEIS instrument is far from its final state, yet. The instrument will be aligned horizontally. Then, they'll do some tests of the noise level transmitted through the tether, before they'll decide how to reduce it. They have several options for doing so, and they finally intend to unroll the tether completely from the tether storage box (TSB).
Handling the tether has been discussed already, above.

[MarkL]

... the InSight program, like all others, has hard constraints in time, money, and personnel; there's never enough of any of those things, so they will of course focus on accomplishing the mission above all else. They do not owe us anything whatsoever in terms of websites translated for our convenience ...

Two posts hidden.[/color]

Translation is available online anyway, and members of this site might also have a crack at translations and post them here. It seems this is one of the many good things that can come from citizen scientists having a way to get involved such as is provided by unmannedspaceflight.com. Panoramas, traverse maps, animations and translations.

That said, proper outreach is vital for several reasons, not the least of which is to encourage strong public support of future missions. It's nice to play with fancy toys in a publicly funded sandbox but the quid pro quo for that is the understanding that common people have to work and earn money to pay the millions in taxes that fund these beautiful missions. So the public has a strong interest in knowing how their money is spent and will be more inclined to vote for future missions if they understand better why it is worth the money.

So I would say they do "owe" us this. But not at the expense of the mission itself, and right now everyone is pretty busy I think.

Mark

[marsophile]

http://spaceref.com/mars/insight-places-a-...er-on-mars.html

There is a spaceref article about the seismometer deployment.

[Phil Stooke]

I just noticed that this sol 18 image:

sol_0018_idc_D001R0018_598131636EDR_F0606_0010M_.PNG

looks so far under the lander that you can see the back footpad. It seems to be sitting on the surface, not buried or partly buried as the other two are. Several of the thruster-excavated pits under the lander are visible as well.

This is a cropped and rotated view of the area:



And this enlargement shows the footpad, identified by arrows:




Phil

[Floyd]

Nice view of the thrusters and how firing change the color of their throats.

[serpens]

I suspect that rather than sinking the landing pads were covered by regolith excavated by the thrusters. The colour change in the pyramidal rock gives an indication of the depth/volume excavated.

Attached thumbnail(s)

 

[Pikaia]

Currently, I don't have the time to translate the whole article.

When translating the news, please make sure that you are always using the original page (don't use a previous copy). I sometimes update the text, to make the facts straight. Waiting a few days after the release could help. For this one, I updated the paragraph related to the arm motion, and then the paragraph about the tether operations (TSB will be open first then LSA - with cable displacement if needed -, and finally deployment of WTS).