[X] My Assistant

[john_s]

Hi folks-

We are deep in the process of planning the Pluto encounter (we're doing it now while all the essential people are still on the payroll!), and following the great success of our Jupiter "Kodak moment" program (thanks Hendric!), we are once again soliciting help from UMSF in planning scenic imaging of the Pluto system. Unlike at Jupiter, the only time when bodies in the Pluto system occult each other is within an hour of closest approach, when we'll be too busy for purely scenic imaging, but there may be interesting alignments or other opportunities at other times.

To help find these opportunities, Henry Throop has kindly made available his New Horizons Geometry Visualizer, NHGV, which is the science team's prime geometry planning tool. It's at http://soc.boulder.swri.edu/nhgv . The tool shows the view of selected targets from the spacecraft at any time during the encounter. Below is some more detailed information from Henry.

More information on the New Horizons instrument capabilities is available here.

We'd like inputs by early June if possible- thanks in advance!
John.

I have developed an on-line, graphical tool for planning and visualizing New Horizons observations. This is a web-based, graphical tool which uses SPICE to plot the position of bodies in the sky, and as they pass through the NH FOVs.

The program is online at http://soc.boulder.swri.edu/nhgv .

Features of NHGV (New Horizons Geometry Visualizer) include:

* Integration with NAIF/SPICE, allowing for accurate positions and observing geometries for planets, satellites, and spacecraft
* Integration with HD and Tycho-2 star catalogs, including access to catalog information such as positions, magnitudes, and stellar types
* Light-time corrections for all computations
* FOVs of all New Horizons remote sensing instruments
* Wireframe images showing position grids and surface lighting
* Albedo and surface composition maps
* Display of Jovian aurora and satelite flux footprints
* Lookup of spacecraft orientation and pointing from SPICE C-Kernels
* Output of all data in graphical and table format
* Flexible input and output coordinates, including both J2000 celestial and ecliptic systems
* Cartesian or spherical projection of sky coordinates.
* Simple web interface
* Observations for a single time or a range of times
* Rapid generation of tables of geometric parameters (distance, phase angle, etc.) over a time interval

It can be thought of along the same lines as Dave Seal's DIGIT or Mark Showalter's Jupiter Viewer, although it has advantages over both (e.g., full access to star catalogs; NH FOV's; web-based; ecliptic coordinates; simple one-page interface). Although it was written for NH, it's really a much more general tool than that. Kernels are currently included for Rosetta, Messenger and Cassini, in addition to NH.

It's used by the NH Science Team for planning future observations, and analyzing previous observations. This is essentially an internal tool that is being released externally on a trial basis, for use in planning potential NH observations. Please let me know of any significant problems.

Extensive on-line documentation, examples, and screenshots are available at http://soc.boulder.swri.edu/nhgv/gv_info.php .

Have fun!

Henry Throop
Southwest Research Institute
Boulder, CO
throop at boulder.swri.edu

[djellison]

I don't think there's any way to do that - all the instruments are essentially bolted to the vehicle and point in a similar direction.

[Alan Stern]

I don't think there's any way to do that - all the instruments are essentially bolted to the vehicle and point in a similar direction.

Doug-- We thought about exactly this in 2001 when the mission was proposed. Various schemes for cameras that showed part of the s/c were considered, but in the end, practicalities intruded and this never materialized. (As an aside I suggest to the MSL team last year that they carry a mirror around that they could deploy to take rover self portraits at various locales.) Regardless, for NH, the imagers are all body mounted and none have s/c in their FOVs, which is the right way to do the science mission, public engagement aside.

-Alan

[vjkane]

Various schemes for cameras that showed part of the s/c were considered, but in the end, practicalities intruded and this never materialized. (As an aside I suggest to the MSL team last year that they carry a mirror around that they could deploy to take rover self portraits at various locales.)

Now that cameras of the capabilities of the MER navigation cameras are lightweight and (I think) pretty cheap, I'd love to see one put at the end of solar panel or other boom to look back at the spacecraft purely for public relations purposes. This would require the project to be willing to add a piece of equipment that doesn't have the same testing requirements as the essential parts of the craft -- i.e., give it your best shot, but it's not a mission requirement.

As it is, I'm delighted that Juno has a camera for public relations, even though it won't see any part of the spacecraft.

[nprev]

This would require the project to be willing to add a piece of equipment that doesn't have the same testing requirements as the essential parts of the craft -- i.e., give it your best shot, but it's not a mission requirement.

I'd love to see that too, but gotta urge caution with respect to requirement definition. If it doesn't have to work & doesn't have a significant mass budget impact, that's all well & good. You'd still have to test it pretty thoroughly at the system level to be certain that it doesn't have a possible failure mode that could take out other mission-critical capabilities, though (power, databus, etc.); what a fiasco that would be!

[vjkane]

You'd still have to test it pretty thoroughly at the system level to be certain that it doesn't have a possible failure mode that could take out other mission-critical capabilities, though (power, databus, etc.); what a fiasco that would be!

Which is why I don't think we'll ever see cameras that can view the spacecraft. Each one introduces a failure mode. As I said, I am just glad that Juno has a camera, although we'll see if it survives the inevitable descope/money crunch that seems to occur in all significant technology designs/development.

[djellison]

Which is why I don't think we'll ever see cameras that can view the spacecraft.

Well - the MI on MER can and does observe PARTS of the spacecraft. If you had an MI that could pull focus, you could photograph bigger chunks of the spacecraft. Like MSL's MAHLI Creative sequencing of the MSL IDD could allow some stitched images that cover quite a bit of MSL.

Doug