Personally I think it is the right decision. Consider that 100m is the size of the largest radio telescopes, the challenges of building an optical 100m are immense. I think it's wise to get some 30m's up and running before thinking about 100m.

That makes sense, thanks for looking it up.

OWL is now planned to be 'only' 30m - 100m was just a bit too overwhelming!

http://www.aviationnow.com/avnow/news/chan.../aw060506p2.xml

12 penetrators, a soft lander and a orbiter all in one!

I hope that the 'one man minding the store' has a stop button if something unexpected happens...

Oops, yes, I wasn't quite with it yesterday.

Is that really true? I thought nearly all these images were downlinked in the end, hence why lots of driving can start to fill up the flash, as these images are not deleted soon after the drive.



Well there are several examples in the tracking database where there appears to be movement e.g.



But after looking at the images

http://marsrovers.jpl.nasa.gov/gallery/all...TTF0006L0M1.JPG
http://marsrovers.jpl.nasa.gov/gallery/all...TTF0006L0M1.JPG

There doesn't appear to be any actual movement - another mystery...

==

btw: Good to see JPL have given up trying to keep up and are using your map now!


James

Just to clarify slightly - Doug's reply makes it sound like the drive number is incremented by one for each image taken. This is nearly always not true. See my plots in this post points are shown with the difference in drive number between consecutive images. Most site/drive numbers have no images (100's at a time sometimes) - I suspect that the drive number is incremented whenever an internal mesurement is taken (rover orientation, etc) not when a picture is taken at a new position. Note there are some cases where a small movement of the rover happens but there is no increment in drive number.

James

The two Navcam frames stitched.

EDIT: Replaced with a better projection.

And in false colour.

Some colour shots of this mess.

Very odd.

I see three possibilities:

1) They saw Michael Howards worry about MMB problems if too many image were taken at one site/drive number and decide to help out.

2) They 'tried' to move the broken wheel.

3) They refined there knowledge of Spirits position (there were a number of 'sun finds' at the time of the change) and defined a new site with the new values.

I'm not sure I beleve any of these though, a question for Jim Bell I think...

James

EDIT: On further investigation it seems that these values change on most sols anyway - even when there is no driving

Because the site number has been reset I can't tell if how far the rover has moved (if any) but I think there has been some motion as the rover orientation has changed:



Don't ask me what there numbers mean I don't really know: they are the 'site_rover_origin_rotation_quaternian_[abcd]' values and I won't pretend to understand quaternians apart from that they define the rovers attitude in some way.

But they wouldn't necessarily take a 'penultimate' if it was only a short drive and the 'ultimate' is a rear hazcam image.

I find it hard to beleve they will move though, lets wait and see...

EDIT: Site change from AR00 to AS00 on Sol 855!

Plan for Sol 835:



Imaging of the tracks using all cameras (hazcam, navcam, colour pancam)

That's from Sol 818.

There was no (attempted) driving tosol (834)

--

This is the most significant downlink of the day:

http://qt.exploratorium.edu/mars/opportuni...G9F0006L0M1.JPG

One of the visidom images that aborted the drive. It's a shame the other isn't down yet as we might be able to see how much Oppy was slipping when the abort was called.

I think your right about this Doug.

And in fact I think the slippage detection worked in this case, it was just unfortunate that, thinking the terrain was good nearby, Oppy was told to go 24 or so meters before checking. I'm pretty sure the drive was aborted early, at the first visidom measurement.

There are two fs_commanded navcams - at the final point and at [final drive no - 2] (i.e a small distance before) I think this is the slippage detection imagery.

Also note there was no turn in place to line up of better UHF passes and it doesn't look like any 'penultimate' images either, all signs of an aborted drive.

---

The fact that at both Purgatory and here the rover thought it had climbed quite a height by being pitched up for so long while driving makes me wonder why that can't be used for detecting this kind of thing? As Oppy drives over ripples the number of wheel turns plus the rover attitude should map out the ripple profiles in a no slip senario. And we know there arn't any 20x2m wide - 2m+ high ripples around here so stop if you appear to be going over one!

Here is the tracking data for Purgatory and the North Erebus Incident (NEI)

NEI

..sol/602..::62::262::-26.2507::11.2459::-0.143594
..sol/603..::62::308::-29.8538::7.33988::-0.498349

Purgatory

..sol/445..::55::136::2.50168::-73.9078::-0.857053
..sol/446..::55::226::14.2636::-154.324::-5.38479

~80m - Oppy only drove ~40m before getting stuck.

Again notice how Oppy thought she had climbed 5.4m by merrily climbing Purgatory for 40m!

So by my reckoning tosols incident is only about half as bad as Purgatory but 4-5 times worse than the NEI.

We'll see in the next few sols - but I'm not too worried yet. Maybe It'll bring my Victoria arrival date back into play (973)

James

You could be right, I assumed it was down by the right hand rule but, haven't looked into if that fits observations.

EDIT: Ah, OK we actually agree, I misunderstood you, as I wrote the wrong thing in my first post. The z (actually c) vector IS down (-ve up) but I should have written that the rover was pitched UP as you correctly pointed out.

I don't think that's the case Doug - there are different numbers for images taken during drives e.g. auto-nav which can't be predicted beforehand. Look at my overlay of Tesh's route map from a few weeks back here. Also there is no way the rover was anticipated to have traveled 2m 'up' - that struck be as unusual when I first looked at the data before the images came down.

That's the distance from the tracking database.

Example:

..sol/832..::71::233::10.5673::-65.9588::-0.0208675
..sol/833..::71::327::12.1891::-89.7695::-2.32683

Last three numbers (I think) are: distance east, distance north & distance 'down' from 7100 in merters. As has been discussed at length in the route map thread these usually tally pretty well with Tesh's route map.

It's also very unusual to see such a large z displacement - I guess what has happened here is the rover knows it was pitched down for the whole drive and so after 24m forward it should have gone down ~2m.

I'll dig up these numbers for Purgatory and Near Purgatory, stand by.

James

Assuming it was (Edit: it was, thanks Tesh) - the tracking site says there was about 5m of driving to get into that (and the rover made 1-2m) in this case we apparently have 24m of driving. Still, a lot less than at Purgatory (50m+ iirc)

I agree Doug it's not anywhere near as bad a Purgatory, I think we'll get out fine.

I do think it's much worse than the other event that we got out of straight away though.

---

Was this the other event?

http://qt.exploratorium.edu/mars/opportuni...FSP1235R0M1.JPG

http://qt.exploratorium.edu/mars/opportuni...FSP1335L0M1.JPG

Dam! Your right.



Anyone remember what sol the NPE was?