Day: November 8, 2012

Self portraits and when losing 40 minutes a day can mean the world

Posted on by Inara Pey

Curiosity is coming to the end of its time at Rocknest, the sandy area in Gale Crater where it has been sifting and examining soil samples and carrying out other experiments over the course of the last few weeks. Glenelg still remains the intended target for the rover, prior to it starting an exploration to the near-central mound in the crater NASA refer to as “Mount Sharp”.

Since my last update on 31st October, Curiosity has been using the Sample Analysis at Mars (SAM) instrument suite to examine the atmosphere in Gale Crate in greater detail. SAM is a remarkably flexible and complex set of instruments, able to analyse air and soil samples a number of ways.

Earlier in the mission, SAM was used to obtain an initial sampling of Martian air “inhaled” at Bradbury Landing. This was subjected to initial analysis by the instrument’s mass spectrometer. Over the last few days, Curiosity has used SAM to further sample the Martian Air, subjecting it to more detailed analysis using a Turnable Laser Spectrometer (TLS).

The TLS shoots laser beams into a measurement chamber which can be filled with Mars air. By measuring the absorption of light at specific wavelengths, the tool can measure concentrations of methane, carbon dioxide and water vapor in the Martian atmosphere and different isotopes of those gases.

This picture shows a lab demonstration of the measurement chamber inside the Tunable Laser Spectrometer, an instrument that is part of the Sample Analysis at Mars investigation on NASA’s Curiosity rover. This demonstration uses visible lasers – rather than the infrared ones on the actual spectrometer – to show how the lasers bounce between the mirrors in the measurement chamber. (Click to enlarge)

Methane is of particular interest to scientists as, while it can be produced by either biological or non-biological processes, it is regarded as a simple precursor chemical for life. SAM represents the most sensitive tool yet deployed on or around Mars which might be capable of detecting methane in the atmosphere. However, the task isn’t easy, as it is probable that if the gas does exist at all within the Martian air, it is liable to do so only in very light traces. Certainly, none wer found in the initial sample analysed by Curiosity’s TLS, as SAM TLS lead Chris Webster of NASA’s Jet Propulsion Laboratory (JPL) confirmed in a press conference I dialled-in to last week.

“Methane is clearly not an abundant gas at the Gale Crater site, if it is there at all. At this point in the mission we’re just excited to be searching for it,” he said. “While we determine upper limits on low values, atmospheric variability in the Martian atmosphere could yet hold surprises for us.”

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SL project news 45/1: viewer updates

Posted on by Inara Pey

Official Viewer

Beta Viewer

The most recent Beta release (3.4.1.266511), released on November 2nd, showed promising signs over the weekend of having broken the back of the memory leak / crash rates problem affecting that branch of the viewer code.

Large Group loading / editing fix in viewers very soon now

Currently, the beta is being merged up to a number of code releases which have been pending in viewer-development, including the viewer-side code for handling large group editing (Group Services project). Commenting on this at the Simulator User Group meeting on Tuesday November 6th, Baker Linden said: “I’ve learned that my group changes have been pulled into the viewer-beta repo, so once 3.4.2 gets promoted, the beta viewer should be able to load large groups.”

An updated version of the beta viewer should be available on Thursday november 8th, which will not only include LL’s own code, but will include a number of open-source contributions to the viewer, including:

  • New media volume controls
  • Ability to block any worn lights (facelights, etc.), on blocked avatars
  • Animation fix for hands (the end of “starfish hands”)
  • Ability to copy SLurls from landmarks in inventory (i.e. “Copy SLurl” will be a context menu option when right-clicking on a landmark in inventory – STORM-1898)

However, Oz has warned that with the upcoming holiday (notably Thanksgiving in the US, the catch-up process may be a little slow as LL work to clear the overall backlog. However, right now, things are looking very good for the viewer as a whole.

Release Viewer

As a result of the progress made with the beta release, the updates in the most recent Beta Viewer (3.4.1.266511, above) were merged into a Release version of the viewer, 3.4.1,266581, and this was rolled out on November 6th. The release notes list the following “resolved issues”:

  • Unable to change parcel restrictions for scripts-disabled parcel in a damage-enabled region
  • Low FPS on high-end AMD/Asus systems
  • Objects by multiple creators show creator as “(unknown)” in inventory
  • Frame stall in updating geometry when region crossing
  • Non standard sea level not correctly rendered around private islands
  • Crash when clicking “back” button after editing appearance
  • Crash on startup for Linux viewers
  • Tcmalloc re-enabled
  • Particle engine rendering issue
  • Memory corruption on Linux in the case of an ll_aligned_realloc_16() call with a smaller new memory size
  • Crash on Exit in 3.4.0(264194) Beta on Win7
  • Disabled realloc
  • Memory leakage fix.

Development Viewer

Similarly, the Development viewer rolled to version 3.4.1.266625 on November 6th, presumably with the same fixes as in the current beta release version.

CHUI

The Lab released an update to the Communications Hub User Interface viewer on the 29th October. The precise changes between it and the original 23rd October release are unclear without examining the update (which I have yet to do), as there is currently no supporting documentation.

The fully expanded Conversations floater in the CHUI project viewer

During the OpenDev meeting on Monday November 5th, CHUI was discussed in general terms and functionality, with some perceived shortfalls being highlighted (such as the removal of the teleport invitation button from individual IM windows). While the right-click context menus within CHUI have been made more consistent with the rest of the viewer (which is a good move), the loss of such convenience buttons is liable to count against CHUI with some users.

There is still no information as to when LL will issue their promised survey on the viewer. As previously reported, feedback from users testing it has been good via the forum thread, and Oz indicated that there has been feedback within Ll on the project as well.

Mesh Uploader Project Viewer

JIRA SH-3055 records a  problem with the official viewer’s mesh uploader which has been affecting people over the course of the year.

On Monday November 5th, Runitai Linden issued an update to the JIRA item, indicating a fix for this problem is available in a project viewer (3.4.2.266471) which is now available for Windows, Linux and Mac OS. Bear in mind that – as Runitai states in his JIRA comment, the viewer is a pre-beat project version, and may include other bugs and problems; don’t try using it as your primary viewer.

However, if you have been experienced mesh upload issues, you may want to give the viewer a try.

You can get it here (all three flavours).