A Dumb MER question

On Sun, 4 Jan 2004 18:53:58 GMT, (Henry Spencer)
wrote:

In article ,
.spade. wrote:
A windscreen wiper?

Could be a really bad idea if the Martian dust is as abrasive as lunar dust.

....It might not be, considering that it does get blown around by the
Martian air, unlike the soil on the airless Moon. Then again, how
difficult would it have been to have brought along an air compressor
to blow the dust off?

OM

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OM wrote:

On Sun, 4 Jan 2004 18:53:58 GMT, (Henry Spencer)
wrote:

In article ,
.spade. wrote:
A windscreen wiper?

Could be a really bad idea if the Martian dust is as abrasive as lunar dust.

...It might not be, considering that it does get blown around by the
Martian air, unlike the soil on the airless Moon. Then again, how
difficult would it have been to have brought along an air compressor
to blow the dust off?

Oh, come now. You've read Dietz... we don't have that kind of
technology.

;P

--
Scott Lowther, Engineer
Remove the obvious (capitalized) anti-spam
gibberish from the reply-to e-mail address

Scott Lowther wrote:

Oh, come now. You've read Dietz... we don't have that kind of
technology.

Ah, your wit continues to inform us of the quality of both
your arguments and your character.

Paul

Paul F. Dietz wrote:

Scott Lowther wrote:

Oh, come now. You've read Dietz... we don't have that kind of
technology.

Ah, your wit continues to inform us of the quality of both
your arguments and your character.

Oh boo-hoo. So which is it: do we have the technology to put an air
compressor on a Mars over, or not? We have not done this yet, so your
arguement, based on recent posts by *you*, would be that we do not have
that technology. Thus my previous post would be in complete agreement
with your position on this matter.

So, you don't like it when people disagree with you, and you don't like
it when people *do* agree with you.

--
Scott Lowther, Engineer
Remove the obvious (capitalized) anti-spam
gibberish from the reply-to e-mail address

Scott Lowther wrote:

Oh boo-hoo. So which is it: do we have the technology to put an air
compressor on a Mars over, or not? We have not done this yet, so your
arguement, based on recent posts by *you*, would be that we do not have
that technology. Thus my previous post would be in complete agreement
with your position on this matter.

We haven't demonstrated that we do, but I'd expect it wouldn't
be that hard. Some development would be required. I would be
concerned about filtering dust, the lifetime of the air filters,
the lubricants used in the compressor, cooling the motor, and operating
the unit in extreme cold.

I would not be willing to say we had this technology until
it had been demonstrated.

Paul

Paul F. Dietz wrote:

I would not be willing to say we had this technology until
it had been demonstrated.

Then you DO agree with the following:
---
Then again, how
difficult would it have been to have brought along an air compressor
to blow the dust off?

Oh, come now. You've read Dietz... we don't have that kind of
technology.
---

Since you agreed with me... "your wit continues to inform us of the
quality of both your arguments and your character" would thus imply that
you either think very highly of my arguement/character, or very
poorly... and thus you think very poorly of your *own* character.

Do not accuse someone else of having poor arguements or character when
they espouse YOUR arguements.



--
Scott Lowther, Engineer
Remove the obvious (capitalized) anti-spam
gibberish from the reply-to e-mail address

In article ,
om@our_blessed_lady_mary_of_the_holy... _facility.org says...
On Sun, 4 Jan 2004 18:53:58 GMT, (Henry Spencer)
wrote:
In article ,
.spade. wrote:
A windscreen wiper?
Could be a really bad idea if the Martian dust is as abrasive as lunar dust.
...It might not be, considering that it does get blown around by the
Martian air, unlike the soil on the airless Moon. Then again, how
difficult would it have been to have brought along an air compressor
to blow the dust off?

Or use a trick that is common on the little video cameras strapped to
race cars for TV coverage of car races: a spool of clear plastic that
unwinds in front of the lens. Given the extraordinary contortions of the
MER rovers, a little motor to wind away the dirty plastic, pulling clean
plastic over the lens should be trivial.
--
Kevin Willoughby lid

Imagine that, a FROG ON-OFF switch, hardly the work
for test pilots. -- Mike Collins

In article ,
OM om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org wrote:
A windscreen wiper?
Could be a really bad idea if the Martian dust is as abrasive as lunar dust.

...It might not be, considering that it does get blown around by the
Martian air, unlike the soil on the airless Moon.

Possibly not, but nobody's sure. There is also thought to be a strong
possibility that the particles are small and the adhesion to the surface
fairly strong, in which case a wiper just won't work (although a brush
might perhaps do better).

Then again, how
difficult would it have been to have brought along an air compressor
to blow the dust off?

In the thin air, it probably requires fairly high gas velocities, not
trivial to achieve.

Last I heard (a paper by Geoff Landis, I think), electrostatic dust
removal was considered probably the best bet.
--
MOST launched 30 June; science observations running | Henry Spencer
since Oct; first surprises seen; papers pending. |

OM om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org wrote:
Then again, how difficult would it have been to have brought along
an air compressor to blow the dust off?

Henry Spencer wrote:
In the thin air, it probably requires fairly high gas velocities,
not trivial to achieve.

The air coming out of a compressor needn't be thin.

Of course that might just substitute one problem (dust blocking the
solar panels) for another (dust clogging the compressor's air intake,
or abrading its pump).
--
Keith F. Lynch - - http://keithlynch.net/
I always welcome replies to my e-mail, postings, and web pages, but
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HTML, "rich text," or attachments, as all such email is discarded unread.

In article ,
Keith F. Lynch wrote:
an air compressor to blow the dust off?
In the thin air, it probably requires fairly high gas velocities,
not trivial to achieve.

The air coming out of a compressor needn't be thin.

It will be by the time it reaches the solar arrays. It'll expand to match
ambient pressure (and thus, more or less, ambient density) before it
covers any significant distance.
--
MOST launched 30 June; science observations running | Henry Spencer
since Oct; first surprises seen; papers pending. |