Ah... that's what happens when you design a planetary encounter in a hurry. We originally planned a full 6-frame mosaic of the Jupiter crescent, including Callisto and Ganymede, but the mosaic wasn't designed in time. I could have claimed the multiple frames were deliberate, in order to get sufficient dynamic range for good exposure of the crescents of both Jupiter and Callisto, but we weren't quite that smart.

John.

Before someone beats me to it, here's an MVIC / LORRI color composite of the sunlit crescent of Io, using the blue and 8900 A CH4 filters on MVIC to show off the red color of the Tvashtar plume deposits at the top of the crescent. The red and near-IR filters were saturated, and there's no Jupiter-shine imaging of Tvashtar because it's on the anti-Jupiter side of Io, so this is the best color we can get on the plume deposit.

John.

Click to view attachment

Who might do that?

It's beautiful; love the red plume deposits. Please please please please please share anything else exciting that you have! I'm finding the MVIC data to be a bit tough to get my head around.

--Emily

Here are a few looking at the sub-Jovian hemisphere of Io in Jupiter-shine. I've attached both the MVIC color images (BLUE, RED, and IR filters) and MVIC color combined with corresponding LORRI frames:

A high definition image of Pluto has been posted on the New Horizons website.

Well, I'd argue against the use of the term "high definition" in this context, with Pluto being 1 pixel across!

Still, nice to see new images from NH!

Does anyone here have a plot of the brightness variations of Pluto as seen by NH? Are we talking about changes of a few percent, or are they larger?

Wow, great pics of Io. It'll be interesting to see, where coverage permits, a Voyager-Galileo-Cassini-NH progression of the evolution of the surface. We've got a 27-year baseline now. It'd be great if we could see what it looked like when Stonehenge was built -- possibly unrecognizable.

I'm sure something along that line could be accomplished.

I don't think the surface of Io 3000 years ago would be completely unrecognizable. Since the Voyager flybys, we have not seen any *new* volcanic centers. Most so-called new volcanoes have generally been reactivations of dormant volcanoes. What we can't say for certain is how long some of the mantle plumes remain active on Io. You might have noticed how when there is a major outburst on Io, neighboring volcanoes also become active. Also, the time-scales of mountain formation and degradation are a little iffy at the moment. How long lived are cold-traps like Colchis Regio? Some of the major ones seem to be tied to regional tectonic stresses and internal circulation (tied to tidal heating). So they maybe relatively long-lived.

In the end, I think Io 3000 years ago would be recognizable. There might be differences in paint, but once you look beyond that, it wouldn't be completely unrecognizable.

I found interesting NH's picture. A series of light reflections revealed internal structure of LORRI telescope.

lor_0035219648_0x630_eng_1
Click to view attachment

LORRI telescope assembly.
Click to view attachment

A good thing too is that from the early 80s on we have had infrared monitoring of hotspots, the resolution of which is ever improving. Also, we have Hubble coverage that can help us keep track of gross albedo features. For example, here is a good WF/PC 2 set from the New Horizons flyby days.

Click to view attachment

Of course, ACS got some views at much higher resolution. After the servicing mission, this will be restored. In fact, even if ACS fails again, WFC3 will have slightly higher resolution per pixel than the PC chip of WFPC/2.

I've downloaded all the LORRI data too, but I can't decompress nhjulo_2003.tgz. It's my problem only ?

Those of you who are messing with the New Horizons data may have (like me) found the INDEX.TAB files to be significantly lacking in the kind of browseable metadata we're used to. I asked some New Horizons folks what the deal was and they said that all the metadata was there in the individual FITS files. That didn't help me a lot, but fortunately Björn "IMG2PNG god" Jónsson has stepped in, downloaded all the LORRI and MVIC data, and combed through the headers for all the images to create a proper metadata table describing all the data. It contains nearly all the metadata available, but not quite all, because Access limits tables to 255 fields. The tables are now in Microsoft Access format and available here:
http://planetary.s3.amazonaws.com/data/met...piter_lorri.zip
http://planetary.s3.amazonaws.com/data/met...upiter_mvic.zip

Is there anyone out there who would like to see these in any format other than Microsoft Access?

Some other comments from Björn:


I have downloaded all the data but am still struggling with a way to automate the FITS to PNG conversion and end up with images with pixel values that are correctly scaled from one image to the next. So I don't have browse pages available yet.

--Emily

Random "are we there yet?" thought of the day: I was wondering when we'd get the first worthwhile images of Pluto from NH, and played around with Solar System Simulator to find when Pluto would subtend, say, 2.5 pixels for LORRI. Just about exactly this time in 2015. So, tighten your seatbelt, occupy yourself with Messenger, Cassini, MRO, etc., and stop asking if we're there yet.

I've been chatting with Dennis Reuter, head of the Ralph instrument, about the MVIC data, and I thought his explanations might be interesting to some of you all, but a bit too technical for my blog:

Posting in two sections because I hit a "you have exceeded the maximum number of quotes" error...

There you have it.

--Emily

Well, that's what a little snooping around will do for you.

I wonder if it's also inevitable for the distortion-corrected frames to look noticeably blurrier than the uncorrected ones (from what few frames I've looked at)?
Resizing or subpixel shifting requires very good algorithms and when I process imagery in Photoshop, I find its resize algorithms (including all bicubic variants) are lacking in that regard, they inevitably blur the image even if all you want to do is accurately align the 3 color channels down to sub-pixel accuracy (say, scaling up 5x, shifting and scaling down). I'm often compelled to live with a slight color fringe in return for having sharper imagery.

Since I've touched the subject, does anyone know of image processing software that implements better resize algorithms (such as lanczos3)?

I would be interested in those index files in Excel format. Access is not installed on any machine I use, either at home or work.

Your wish is my command

http://planetary.s3.amazonaws.com/data/met...er_mvic.xls.zip
http://planetary.s3.amazonaws.com/data/met...r_lorri.xls.zip

--Emily

Sweet! Thanks!

The LORRI link is broken though. I get an XML Access Denied page.

Whilst discussing MVIC / Ralph - here's a shot of the spare CCD they have at the London Science Museum, and a map from the PDF here : http://www.boulder.swri.edu/pkb/

Up close, these things ( when not filthy dusty ) are very pretty - lovely colours from different angles.

Doug

Oops. Try it again now.

Works now thanks!

Thanks Bjorn and Emily! I think even those of us on the New Horizons team might find those spreadsheets handy.

John.

I guess I'm lazy asking here instead of reading the documentation but I really want to start digesting the NH images by converting them to PNGs ASAP. I now have a working FITS to PNG converter (actually it's a part of IMG2PNG); only a few minor 'tweaks' are left.

So here I go:

(1) Does anyone know what those three images in each of the LORRI files are? The first two look similar but most (all?) of the pixels in the third one are of uniform brightness.

(2) The MVIC files contain four images. I haven't looked closely at them yet but the fourth one seems very uniform (the resulting PNGs are small, meaning it compresses well). Is it correct that images 3 and 4 contain information on errors and data quality as was stated in an earlier messages in this thread? Image 3 looks like a 'real' image so I'm a bit surprised if this is the case.

Arg! Internal server errror lost my message the first time around! Here goes again...

You want the ICD for this information. Section 9 for LORRI, 10 for MVIC. You should probably read these, they're informative on what exactly each extension is, and also on what's corrected and what's not in the calibration (for instance, readout smear correction on LORRI doesn't work so well when there are saturated pixels). Copying from each section:

LORRI:
9.2.1 Data Format
The raw image data is organized in a FITS file. The primary header and data unit (HDU) is used to store the reconstructed image from telemetry. Additional data are stored in the extensions of the file. The two tables below contain a description of the layout for the extensions for raw data.
As described previously, LORRI operates in two binning modes: 1x1 and 4x4. For the 1x1 binning mode, the raw image dimensions are 1028x1024 where columns 0 through 1023 are the optically active region of the CCD and the remaining columns (1024-1027) are from optically inactive region (dark columns) of the CCD and represent a temperature-specific measurement of the bias value. For the 4x4 binning mode, the raw image dimensions ar 257 x 256 where columns 0 through 255 are optically active and column 256 for the dark column.
FITS File Storage Location Description
Primary HDU Reconstructed image from telemetry
First Extension histogram from image descriptor packet (APID 0x611)
Second Extension Instrument housekeeping from first 34 pixels
Third Extension Matching image descriptor




MVIC:
Table 10.2 Observation Modes and their filename prefixes and data dimensions
Detector Prefix for FITS file Dimensions of data in FITS file
Pan Frame Mpf 3 (5024 x 128x Ni)
Pan 1 mp1 2 (5024 x Nr)
Pan 2 mp2 2 (5024 x Nr)
Red mc0 2 (5024 x Nr)
Blue mc1 2 (5024 x Nr)
NIR mc2 2 (5024 x Nr)
CH4 mc3 2 (5024 x Nr)

The Level 2 FITS file has a primary data unit which contains the bias-subtracted, flattened image (or image cube in the case of pan frame) plus 4 extensions. Extension 1 is the bias-subtracted, flattened, distortion-removed image (or image cube). Extension 2 is an array with the per pixel error of the bias-subtracted, flattened, distortion-removed image (or image cube). Extension 3 is an array with a data quality flag for each pixel of the bias-subtracted, flattened, distortion-removed image (or image cube).

Table 10.2 Pan Frame Image Data Format
FITS Data Unit Dimension Description
Primary 5024 x 128 x Ni Bias-subtracted and flattened image cube
Extension 1 5024 x 128 x Ni Bias-subtracted, flattened, distortion-removed image cube
Extension 2 5024 x 128 x Ni 1-sigma error per pixel in extension 1 image
Extension 3 5024 x 128 x Ni Data quality flag of extension 1 image

Table 10.3 TDI Image Data Format
FITS Data Unit Dimension Description
Primary 5024 x Nr Bias-subtracted and flattened image cube
Extension 1 5024 x Nr Bias-subtracted, flattened, distortion-removed image cube
Extension 2 5024 x Nr 1-sigma error per pixel in extension 1 image
Extension 3 5024 x Nr Data quality flag of extension 1 image


If IMG2PNG can output all the images it would be loverly. But maybe that's asking too much. Doesn't keep me from asking though

--Emily

Thanks - seems to be exactly what I need.


It already does . A number gets added to the name of the output file to distinguish between the images.

Please open whatever (MVIC, LORRI, Alice, SWAP) NH's file using program "Fv viewer" and all will be clear.

LORRI
Click to view attachment

ALICE
Click to view attachment

I just realize that there are two versions of the "Io-Europa crescents Kodak moment picture":

http://pluto.jhuapl.edu/gallery/sciencePho...pics/040207.jpg

and

http://pluto.jhuapl.edu/gallery/sciencePho...pics/101607.jpg

The second version has an improved resolution (LORRI), and the two moons positions are quite different.
Is this reflecting the real movement of the moons between the times when the MVIC and LORRI pictures were taken ?
Marc.

Based on the results from the Voyagers and from NH's SDC instrument, could we calculate what's the friction all the way to Pluto and beyond and how much delta-v will NH loose due to that friction? I know friction in space is negligible, but given that NH will travel "consciously" for at least 10 years (hopefully even more), this should accumulate. The Voyagers have been traveling for some 30 years now and they should have sensed it even more.

Actually, I would expect that any effect due to 'friction' would work in the opposite direction, since the solar wind is moving outward more quickly than NH.

Although any effect is doubtless tiny.

Using the drag equation and assuming a density of 10^-18 Kg/m³ (valid in the internal solar system), the pressure associated to a relative speed of about 20 Km/s is of the order of 10^-10 Pa. For comparison, the pressure radiation of the Sun at the Earth distance is 4.6 µPa (absorbed), many thousand times bigger (!).
If the probe has a typical size of 4 m and a mass of 1 tonn, the friction force is close to 1 nN with a deceleration of 10^-12 m/s² or 1 mm/sec in 30 years. Obviously, real velocity loss should be lower in the case of a probe moving in the external solar system, where medium density is lower; considering medium density decrease in reason of R^-2, at 30 AU you should reduce these figures by 3 orders of magnitude!
Following Mong suggestion, if we consider solar wind velocity, the force is bigger and directed outward; assuming a relative speed of 400 Km/s, this means a 400-fold pressure and deceleration, which still tiny.
Final consideration: the Earth is experiencing similar pressure for billions years and effect on its orbit is negligile...

On a related topic - some new work on the Pioneer anomaly. A team have built very detailed thermal model of the spacecraft and have accounted for something like a third of the distance Pioneer is today from where it'd be expected to be. Over long periods of time, tiny effects like the pressure difference of a few photons more coming out over here than over there accumulate, slowly and relentlessly...

"And the immense amounts of work that have to go into trying to model the system
properly is quite incredible. Scientists need to dig out information from decades ago
to try to get everything they need and there are a lot of uncertainties. Turyshev
quipped, “It’s like being on CSI.”"

http://www.symmetrymagazine.org/breaking/2...o-being-boring/

Nice little animation of the Pluto encounter created in Celestia (91 MB zip that unzips into a 119 MB AVI file, may require Windows Media Player):

http://pirlwww.lpl.arizona.edu/~perry/Cele.../Encounter2.zip

....As has been my habit in past months, UMSF gets the advance copy:


The PI’s Perspective
01 May 2008

Green Beacons for a Golden Bird


[IMAGE: New Horizons with its golden Mylar thermal covering.]

As you read these words, the New Horizons spacecraft remains in a long period of almost continuous hibernation that we entered in February 21st that which will stretch until September 2nd. During this time the spacecraft will fly from 9 to almost 11 times as far from the Sun as the Earth is, covering over 300 million more kilometers! And with the exception of a single, two-week high activity period that begins on May 20th, the spacecraft is running on its own, and doing little besides checking into report status each Monday and to deliver a brief telemetry report most Thursdays. These contacts have shown that things are going well: all of the weekly status reports (technically called “beacon tones”) have been green, and all of the telemetry passes have shown that the spacecraft is performing well.

Although our spacecraft has been hibernating, our ground and science teams have not been quiescent at all.

Planning for the Pluto encounter is in full swing now, with the goal of completing all of the near encounter sequence design and testing within about a year, so that we can conduct a full scale rehearsal on New Horizons in mid-2009. In fact, just this week we completed a formal review called the Encounter Requirements Review. This review’s purpose was to verify that, before we begin designing the detailed encounter sequences, we have in hand a fully complete list of every scientific and navigation activity that we plan to conduct during the encounter. In June we will conduct our formal Encounter Feasibility Review, in which detailed encounter plans will be tested against dozens of ground and spacecraft constraints such as power, data storage, and available fuel, to ensure that every aspect of the developing encounter plan is fully feasible. That review will be followed in August with a full up Preliminary Design Review (PDR) for the encounter, after which detailed sequence building will get underway. July of 2015 may be seven years away on the wall clock, but with our need to reduce our team size and budget after 2009, New Horizons must complete its encounter planning, ground testing, and a full dress rehearsal on the spacecraft barely more than one year from now!



[IMAGE"
Large antennas like this one, in Canberra, Australia, form the Deep Space Tracking Network (DSN) that NASA uses to track missions beyond Earth orbit. In addition to transmitting commands and receiving telemetry fro New Horizons, this particular antenna will be used on 14 July 2015 to generate the radio occultation signal that our spacecraft will use to probe the temperature and pressure profile of Pluto’s atmosphere. ]


The New Horizons ground team is also busy with sequence planning for this fall’s spacecraft and instrument checkout period, which will run from September 2nd through mid-November. In addition to the annual series of tests, this fall’s activities will also include the uplink of new command and data handling, guidance/navigation, and fault protection software that resolves several dozen minor bugs and provides some new capabilities that will improve our ability to perform at Pluto and in the Kuiper Belt. The ground team is also completing the build and beginning to test “NHOPS II,” our second (and long desired) backup New Horizons spacecraft simulator, which will be operational at the Applied Physics Lab (APL) by late summer.

I mentioned that we plan to wake up New Horizons for a couple of weeks beginning on May 20th. The primary purpose of this wakeup is to re-point our spacecraft antenna to account for the motion of the Earth around the Sun. We have to conduct such re-pointings a number of times each year, and we use these as opportunities to group together important activities that need to occur between annual checkouts.

In the upcoming wakeup, spacecraft activities will include navigation ranging tests that mimic Pluto operations, spacecraft tracking, the downlink of accumulated impact data that the SDC dust counter instrument has collected so far this year, a bug fix software load and subsequent test of the SWAP solar wind plasma instrument, and an upload of the spacecraft command sequence that will take it from 3 June to 5 September.

The last thing I’ll mention is this update is that our project secretary, JoAnne Kierzkowski, retired a couple of weeks ago. JoAnne worked at APL for many years, and came to the New Horizons project at the start—when the team formed in December 2000.

JoAnne provided expert project coordination to us, from the start of our proposal writing, through spacecraft design, build, test, launch and the first 1.5 billion kilometers of travel on the road to Pluto. Although she isn’t going far and will be celebrating with us at the Pluto encounter in 2015, we will miss her work and her cheerful smile every day in between.

Everyone on New Horizons will miss our retiring secretary Joanne Kierzkowski, who began with the project team at its inception in late 2000.

Well, that catches you up with where New Horizons is and what the spacecraft and project team have been doing. I’ll be back with more news soon. In the meantime, keep on exploring, just like we do!

-Alan Stern

And we very much appreciate it, Alan; thank you! Glad to hear she's running smooth.

Thanks for the update Alan.
Glad to know that the Canberra DSN will be on duty for the New Horizons Pluto encounter.

I know it's seven years away but we're already excited. From an education/outreach point-of-view, the public are very interested in this mission and your updates provide a great resource of regular news and information that we can pass on.

We hope to get the chance to see you downunder some day soon.

Astro0

Astro0-- I'd like to finally do that. DSN's Rich Benson is working some dates for this June or September.

Alan

Thanks from me, too, for the update Alan. There's a lot of interest in NH here in the UK, and the schoolkids I talk to are always fascinated by the whole subject of Pluto. Great to get your updates here on UMSF!

Thanks from me too! NH is probably the most famous ongoing space mission in Bulgaria. There are articles and update threads in various forums and websites. Even in non-space ones! A fantastic mission! Hoping to see more missions to new destinations in the future. Good luck!

UMSFers-- My new NH project news update is at: http://www.pluto.jhuapl.edu/overview/piPer...ive_current.php

-Alan

Caption below last image in latest PI perspective:

funny I didn't know Charon had its own moon.

Further detailed observations by Cassini of Enceladus, Rhea and the rest of the Saturn ring system during its extended mission can help refine our knowledge in the years to come as NH approaches the Pluto system. In that sense, waiting several more years for the Pluto encounter may not be so bad after all!

Interesting info about Pluto's atmosphere & its interaction with Charon, Alan; thanks! Do we have any idea at all what the current surface pressure might be, or what that atmosphere's total mass is? I'm guessing a few millibars at best, but the exceedingly weak surface gravity might make that estimate too high.

I didn't know that Pluto was undergoing self-sustaining nuclear fusion!

[The base image is actually one showing the Sun (labelled "Pluto") and the Earth-Moon system (labelled "Charon").]

Some obscure cults already claim there is life on Charon. Scientists remain skeptic.

Inversion of the refractive phase delay from stellar occultations indicates a pressure of a few to perhaps 60 microbars, Nprev-- at most about 1% the Martian pressure.

Alan

If i recall, the Martian surface pressure is 0.7% of Earth's, so this would be 0.00007% of Earth's surface pressure. Don't forget the spacesuit!

Wow...that's just mind-blowingly thin, yet it's enough to foster frost formation! Thanks; that broadened my own horizons a bit with respect to what is possible.

If I did my units conversions right (table of pressure units), that works out to 46 microns of Hg.

Our current laboratory high vacuum line is pulling about 1400 microns of Hg. So Pluto has 30x LESS pressure than our laboratory vacuum line.

-Mike

And actually, the pressure (~10 microbars), temperature (~105K), and composition (N2-dominated) in Pluto's troposphere, are each very much like the same parameters in Earth's mesosphere, 80 km overhead, where noctilucent clouds form.

-Alan