Mars Exploration Rovers Update - February 27, 2004

http://www.jpl.nasa.gov/mer2004/daily/2-27-04.cfm

Spirit Status for sol 54
Heading To 'Humphrey'
posted Feb. 27, 5 pm PST

On sol 54, Spirit woke up to the song "Big Rock in the Road" by Pete
Wernick and made its final approach to the imposing rock called
"Humphrey" before the sol ended at 5:13 p.m. PST on Friday, Feb. 27.
The initial 3.5 meter (11.5 feet) drive toward the rock was cut short at
only 2.5 meters (8.2 feet) due to a built-in software safety. Rover
engineers quickly adjusted the software restriction and drove the final
meter of that planned drive, plus the 0.9 meters (about 3 feet) that put
the rover in the best position for brushing "Humphrey" with the rock
abrasion tool.

Before approaching the rock, Spirit used its alpha particle X-ray
spectrometer to investigate the areas the rock abrasion tool will brush
and grind. Unlike the last rock abrasion tool sequence on the rock called
"Adirondack," the planned procedure for "Humphrey" will include
brushing three separate areas of the rock. After brushing, Spirit will
back up and examine the brushed areas with the instruments on its arm.
The science team will then decide the best place to grind into
"Humphrey" - it could be one of the three brushed areas or another
section altogether. The hope is to remove as much dust as possible so
the instruments on Spirit's arm can get a pre-grinding "read" on the
rock coating and then, after grinding, study beneath the coating and
surface.

In the sols following the rock abrasion tool sequence, Spirit might
investigate an interesting rock behind it, or continue on toward
"Bonneville" crater.



Opportunity Status for sol 33
Biting Blueberry Hill
posted Feb. 27, 10:30 am PST

On sol 33, which ended at 4:55 a.m. Friday, February 27, Opportunity
reached its second rock abrasion tool target site, and it's ready to take
the next bite of Mars.

Opportunity woke up a little late on sol 33 to conserve energy. The
wake-up song was 'Blueberry Hill' by Fats Domino, in honor of the hill
in front of the rover.

Opportunity took an early afternoon 360-degree panorama and an extra
observation of the area to the east with its navigation camera, while the
Moessbauer instrument completed the measurements it began on sol
32.

The microscopic imager also took three sets of observations of the hole
created by the rock abrasion tool on sol 30. Opportunity later took
stereo images of the rock area named "Maya" and took pictures of an
area called "Half-Dome." Both the panoramic camera and the miniature
thermal emission spectrometer observed the sky.

In between science measurements, Opportunity stowed its instrument
arm and drove a 15-centimeter (6-inch) "bump" to reach its next rock
abrasion tool target. Final shutdown was at 2:37 Local Solar Time, with
a brief wakeup at 4:10 Local Solar Time to transmit data to the Mars
Odyssey orbiter as it flew over the rover.

The plan for the weekend is to grind into the upper part of "El Capitan"
dubbed "Guadalupe" and to take extensive measurements of the new
hole using the microscopic imager and two spectrometers.

Does either of the rovers have enough strength to push a rock
so that it rolls down a slope?

Not only would it be interesting watching the rock roll down a
slope, but it would be interesting to look at the trail that
it leaves behind in the dust. If a rock strikes another rock, maybe
one of them could be fragmented somehow.

Has either of the rovers attempted to do this sort of thing?

Or are the valleys between the hills too shallow to have a rock
roll down between them?

|Not only would it be interesting watching the rock roll down a
|slope, but it would be interesting to look at the trail that
|it leaves behind in the dust. If a rock strikes another rock, maybe
|one of them could be fragmented somehow.
|
|Has either of the rovers attempted to do this sort of thing?
|
|Or are the valleys between the hills too shallow to have a rock
|roll down between them?

If Mars is more or less geologically dead - or dying - what other
mechanisms are there for shaking loose an avalanche here or there?

Wind? CO2 deposition as a burdensome overlayer of some kind, causing
collapses and rolling?

"Matthew Montchalin" wrote in message
...
Does either of the rovers have enough strength to push a rock
so that it rolls down a slope?

Not only would it be interesting watching the rock roll down a
slope, but it would be interesting to look at the trail that
it leaves behind in the dust. If a rock strikes another rock, maybe
one of them could be fragmented somehow.

Has either of the rovers attempted to do this sort of thing?

Or are the valleys between the hills too shallow to have a rock
roll down between them?


Ther is not enough of a slope agt either site in order to do this. But why
would you need to do it anyway? The rovers have a rock abrasion tool that
is used to examine the interior of any rock, and the tracks of the rover
wheels make plenty of marks on the Martian surface.

"Matthew Montchalin" wrote in message
...

Does either of the rovers have enough strength to push a rock
so that it rolls down a slope?

If the rovers encountered a slope steep enough with a precariously
balanced rock convieniently placed, it might be possible to send
it on its way with one of the wheels.
It is unlikely the arm has the strength. More importantly, the risk
of tweaking the various instruments out of alignment or damaging
them outright would preclude the use of the arm for that purpose.


Not only would it be interesting watching the rock roll down a
slope, but it would be interesting to look at the trail that
it leaves behind in the dust. If a rock strikes another rock, maybe
one of them could be fragmented somehow.

Has either of the rovers attempted to do this sort of thing?

Not intentionally.

Or are the valleys between the hills too shallow to have a rock
roll down between them?

The sites were chosen, in part, because of their flatness. The
rovers have not yet encountered a steep enough slope.
There might be a candidate slope at the crater Bonneville which
is a destination of Spirit.

George wrote:
|"Matthew Montchalin" wrote in message
...
| Does either of the rovers have enough strength to push a rock
| so that it rolls down a slope?
|
| Not only would it be interesting watching the rock roll down a
| slope, but it would be interesting to look at the trail that
| it leaves behind in the dust. If a rock strikes another rock, maybe
| one of them could be fragmented somehow.
|
| Has either of the rovers attempted to do this sort of thing?
|
| Or are the valleys between the hills too shallow to have a rock
| roll down between them?
|
|Ther is not enough of a slope agt either site in order to do this.

Hmmmmmm

|But why would you need to do it anyway? The rovers have a rock
|abrasion tool that is used to examine the interior of any rock,
|and the tracks of the rover wheels make plenty of marks on the
|Martian surface.

The way a rock falls apart tells us a lot about the way it is put
together. Igneous rocks probably require a much higher distance
to fall than do sedimentary rocks. But better yet, is seeing if
a number of rocks can be moved all at once, and whether the surface
has a uniform layer of dust on it, or whether some places are
deeper than others. It also serves to show whether wind is the
main depositing force in the area, or whether seasonal CO2 deposits
might have deposited some of the dust in the area.

Then again, why trigger an avalanche? Well, maybe I am just a whole
lot more curious than you are. Maybe it takes a lot more work to
do that sort of thing on Mars.

Chosp wrote:
|"Matthew Montchalin" wrote in message
...
|
| Does either of the rovers have enough strength to push a rock
| so that it rolls down a slope?
|
|If the rovers encountered a slope steep enough with a precariously
|balanced rock convieniently placed, it might be possible to send
|it on its way with one of the wheels.

hmmm

|It is unlikely the arm has the strength. More importantly, the risk
|of tweaking the various instruments out of alignment or damaging
|them outright would preclude the use of the arm for that purpose.

Okay, that's a good point. It's not like the rovers were designed
to be bulldozers.

| Not only would it be interesting watching the rock roll down a
| slope, but it would be interesting to look at the trail that
| it leaves behind in the dust. If a rock strikes another rock,
| maybe one of them could be fragmented somehow.
|
| Has either of the rovers attempted to do this sort of thing?
|
|Not intentionally.

Okay.

| Or are the valleys between the hills too shallow to have a rock
| roll down between them?
|
|The sites were chosen, in part, because of their flatness. The
|rovers have not yet encountered a steep enough slope.
|There might be a candidate slope at the crater Bonneville which
|is a destination of Spirit.

Thanks, that's good to know.