Paul Rosen, jpl, par@parsar.jpl.nasa.gov
QUESTION09
09-1 The Gatineau receiving station should have a list of orbital elements and insertion times for each phase since launch. I know that the Alaska SAR Facility in Fairbanks has such a list because they gave me a printout last fall to update JPL's EOSMENU ground coverage software. Unfortunately, the list is under piles of paper somewhere on my desk. Give me time to "search" and I can probably help you, otherwise if you need the information soon, contact the Gatineau station, or ASF.John Crawford, JPL Ocean Sciences, jpc@chukchi.jpl.nasa.gov
QUESTION08
08-1 NASA has asked the Committee on Earth Studies (CES) of the National Research
Council Space Studies Board for a scientific assessment of SAR data for Mission
to Planet Earth. The CES held its first workshop on this subject in Irvine
California from January 9th to 13th. Based on the results of this workshop, they
will advise NASA as to the value of a third flight of SIR-C/X-SAR relative to
other proposed mission concepts. A decision whether to refly should be made
sometime this spring.Diane Evans, JPL
QUESTION11
11-1 I would like to see a clickable map that would let me zoon in on image files pertaining to my area of interest (Oregon). This would be more convenient than long document lists, some of which are hard to pinpoint from the name alone. With WebMap 1.01, it is easy to convert arbitrary polygonal regions into URL's.Tom Pringle, Emerald Imagery,
11-2 When I have a chance (sometime in the next month) I will
be implementing a clickable map or the world for the picture gallery.
At the Eros Data center (go to science and applications, how to get
data), there is a clickable map of the world, where you can view
the survey data from SIR-C.bruce chapman, Jet Propulsion Laboratory, bruce.chapman@jpl.nasa.gov
11-3 We have made a few changes to the bulletin board recently.
Now, the whole question is clickable. Also, the date of any entry
is now listed at the end. The box to click on to submit a
question is now also at the top of the page. 1/26/95bruce chapman, Jet Propulsion Laboratory, bruce.chapman@jpl.nasa.gov
11-4 I would like to see a 3D RADAR image of the Santa Clairita
Valey. It would include Valencia,Saugus & Canyon Country. 1/29/95Henry Armstrong, A.C.C.S. LABS, hca3@smartdocs.com
11-5 We have an image of the LA area that comes down from San
Francisco. Some of this image is at the picture gallery, I
am not sure if it goes as far north as Santa Clarita .
However, I do not think that we have any 3-d data from this area,
so unfortunately, at this time I can not put a 3-d image on-line.
In order to get 3-d imagery, we currently have to use either airsar/topsar
data (which is a NASA/JPL airborne sensor), or by using repeat
passes over the same area by SIR-C, J-ERS-1, or ERS-1. This kind
of data is not available for a large percentage of the Earth. 1/30/95bruce chapman, jet propulsion laboratory, bruce.chapman@jpl.nasa.gov
11-6 is there a way for me to find out if a new response has come in since i last looked at a question/response? the best would be if netscape would "un-red" the question in the main list if a new response came in...
thanks 2/ 2/95Tom Farr, JPL
11-7 Reponse to 11-6: We are thinking of adding the date of the last response after
the number of responses in the BB. Forcing netscape (or any other browser) to
"un-red" a hotlink based on a users local BB history file (that would need to be
created) is a bit more complicated than we want to get into at this time. 2/13/95Sharon Okonek, JPL, sharon.okonek@jpl.nasa.gov
11-8 This is an 'issue' for me too. Basically, we have a sorted database with three fields: questions, responses, and date submitted. Using standard html form yoga and a modest cgi script, responses could be compiled automatically as a database sorted by date and linked to the appropriate question. Then, responses not previously seen by particular individuals would show as blue and likely clustered near the top. It might be fun to see a response and guess what the question was!
This would be groundbreaking work but well worth it -- Ric Ford of MacWeek has been looking at this home page on and off with a view to featuring it in a future column. 2/18/95
tom@emerald
QUESTION03
03-1 This "Submit a Response" box is pretty. I'd rather it scrolled down like a notepad weird on my Mac. It just goes and goes to the right and I can't see what I just wrote.Tom Pringle, Emerald Imagery, tingalsb@oregon.uoregon.edu
03-2 Unfortunately, that is a property of the forms. 1/26/95bruce chapman, Jet Propulsion Laboratory, bruce.chapman@jpl.nasa.gov
03-3 Solution A: Stub in the following html code to JPL home page after
Enter your question or comment in this box:
Solution B: Mac Netscape users can View>Source... to open Simple Text, start writing at bottom, then paste into comment box. 1/27/95
anonymous
03-4 In 03-3, the stub-in code got taken too literally as html, not text. Intended change just sets columns to 110, which makes text box appropriate for an average screen and drops it to its own line. The larger box is easier to work in. 1/27/95anonymous
03-5 I think this is what was meant above: I took the liberty of editing this out, as I found it confusing. basically, this person put in a response box of 110 columns. We have changed the size of the response box to 80 characters (bc)
03-6 It might be nice to have a cancel or edit option at the point where the user sees how a given question or response is going to look. Here's an easy workaround (surf your own hard drive): view the current page as source. This opens the SimpleText editor. Select All and Cut. This gives a blank slate. Write out the question or response. Save As anything.html to the desktop. Back in Netscape, Open File and double click on your new .html document. View the document just as it will appear on the JPL home page. Save changes as needed. Copy and paste into the 'Submit Comments box and submit! 2/ 1/95
03-7 I changed the width of the text area from 60 to 80 chars. Hope this helps. 2/ 2/95Sharon Okonek, JPL, sharon.okonek@jpl.nasa.gov
QUESTION10
10-1 The SIR-C Project has created an Educational CD-ROM called the SIR-CED.
This CD contains radar images and tutorials that allow students to learn
about the uses of radar. There is a detailed write up on the CD-ROM on
the "radar remote sensing education" section of the Imaging Radar Home
Page. This section describes the CD-ROM and gives information regarding
ordering copies for use in the classroom.
Also mentioned in this section is the type of computer equipment
needed to display the images from the CD. 1/26/95Shannon L. McConnell, SIR-C Project
10-2 I have been using the SIR-CED disk since this last summer with
high school students and I have developed a unit around the
Pennsylvannia image. The week-long computer lab exploration
uses the Radar Image and Landsat and digital photographs to show
students the problems of Coal Mining and the problem of Acid
Mine Waste. Write me for details- BOX 163 Lincoln, VA 22078
(PS Once I'm comfortable on the net I will link and have e-mail) 3/ 8/95William M. Seebeck , Chantilly High School, Fairfax County Schools,VA, none yet
QUESTION13
13-1 Eventually all SIR-C data will be made available through the
EROS Data Center in Sioux Falls, SD. It's going to take a
while before the interferometric data (which was acquired
experimentally) is released.
We (JPL) have an airborne interferometric SAR system which
is now operational called TOPSAR. It can generate high
resolution topo-data over areas of ~10x10km. Some limited
amounts of TOPSAR data have been released. For further info
on TOPSAR or TOPSAR data send an e-mail to:
radar.queries@jpl.nasa.gov 1/26/95Tony Freeman, JPL
QUESTION04
04-1 I think this is a really good idea. There are a zillion directions to go off in for 5-channel enhancements -- it would be fun to see what others can come up with since nobody has time to explore them all. To be helpful, enhancement goals, software used, and enhancement steps taken need to be articulated and perhaps edited for consistency. I propose that JPL create a contest (with prizes of course) to see who is the most inventive and skillful at extracting information or making an educational point from radar imaging data. This would consist of posting, say, all channels of some scene at 200K x 5 = 1 meg, setting an enhancement objective, a time frame, a panel of judges, and incentives (CD-ROMs of radar data?). Many of us could productively waste time on this at work because our screens would look okay. 1/28/95Tom Pringle, Emerald Imagery, tingalsb@oregon.uroegon.edu
04-2 I think this is a great Idea! I spoke with Tony Freeman about it
and he agreed. We will try to put a contest like this together.
I will be a bit busy for a couple of weeks on other things, but I
will try to organize something by the end of March.
By the way, we actually have 13 channels of data when we collect
all channels (X-band 1 channel, L-band 4 channels, C-band 4 channels)
so we will put all of them on-line, and then let the users have
their hand at making some nice looking images!
I will announce it at whats new, and at the bulletin board. 1/30/95bruce chapman, Jet Propulsion Laboratory, bruce.chapman@jpl.nasa.gov
04-3 correction (see question 20) . I will put 7 channels of data
on-line. (maybe only 6 if I can not get the corresponding x-band data.) 2/ 1/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
04-4 I think the grand prize should be a ride on the Shuttle (provided the winner has the 'right stuff.') Or at least on the TOPSAR DC-8. Not just some CD-ROM. 2/ 1/95
QUESTION15
15-1 Yes, this works. Sort of. JPL has set up the whole nine yards to be underlined so it is hard to tell that the Eros link does work in the original question. While it is not my place to offer design changes to JPL's most excellent home page, bulletin board users who want to see a little less underling in their question could submit it so that only the first word is the link to the responces. From question 15, viewed as source, it is clear that inserting a terminator (/A, sandwiched by 'less than' and 'greater than' symbols) where the underlining should stop is enough. Then the links within their question would show up better. Note that this is only necessary in submitted questions; in submitted responses where links would be more common, they show up fine.
1/28/95
15-2 We really like this idea of putting in links within the questions.
We will probably change the format so that the whole question is
not underlined, so that it is more clear where a link is... 1/30/95bruce chapman, Jet propulsion laboratory, bruce.chapman@jpl.nasa.gov
15-3 as shown in the response to question 1-10, if you put in a
link to something within the imaging radar home page, don't forget
that you have to specify the path, including the top "/", or
it won't link correctly. If it is a link outside of the
imaging radar home page, then you don't have to worry about
that. 1/30/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
15-4 I would like to inclose small graphics as well as links in my responses . However, "Submit a Response" does not seem to accept pasted graphics. Can JPL give us a stable directory path to a folder where we might ftp our images with Fetch, then cite in question or response links? Or would you rather we did these links to our own home pages?I see where someone has done an end run around the name-affiliation-email paperwork by creating a single paste 'send mail' trigger link in question 22. Can you set things up so all email addresses are provided like this automatically? 2/ 1/95
15-5 Well, I'm not sure. I am not sure if the link in 22 was
manually input. It might only be a netscape feature. It may
be possible if the netscape software can handle it... 2/ 1/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
15-6 So far as linking in graphics at the bulletin board, this is
certainly an interesting idea... 2/ 1/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
15-7 After talking it over, we have decided not to enable linking small
graphics into the bulletin board with the img src html command, as
then we start having to worry about the amount of disk space that
we would have to allocate for this (once it is in a question, we have to
keep the image as long as we keep the message). And then there is
the problem of inappropriate images. As it is, you can
put a link to an image, you just have to click. If you have an
image that you would like everyone to see, then send me an email,
and we can possibly put it into the
| Imaging Radars |
| AIRSAR | SIR-C |
| SIR-B | X-SAR |
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3/26/95
QUESTION14
14-1 Tom, a very interesting problem. I wonder if the ion-rich river water would be too much of a conductor to allow radar depth mapping, though it should pick up sandbars and shoals. At $500M a pop for shuttle flight, that's going to make a pretty expensive load of soyburgers by the time it gets out here to Oregon. First tell us why an ordinary color Walmart camcorder flown down the river weekly in the belly of the company plane doesn't make something that the captain can look ahead with on his VCR. Your response is probably, this works fine, but it's not high tech enough for us at Marine Equipment plus it doesn't show enough river depth. Okay, here's what you do. Run the video frame-by-frame through an enhancement cycle in Adobe Photoshop, then do a PCA analysis in DIMPLE, under-tinting a supervised classification to draw out the features, and over-vectoring with river charts and DEM GIS data. Dollars will get you donuts that the best channel will pop right out in vivid color. Now drive the VCR frame-by-frame with your GPS satellite downlink to barge river position, so the captain only sees the next mile or two. Or better yet, set the barge up as a Web site, pilot it remotely with a clickable map, and forget the video. 1/28/95
14-2 Interesting problem and response #1 is a neat partial solution. It is true that the radar waves will not penetrate significantly into the water, while short visible wavelengths, like blue and green, will. Silt, etc. in the water would limit this unpredictably, though. 1/30/95Tom Farr, Jet Propulsion Lab, tom.farr@jpl.nasa.gov
14-3 Fellas, that was a pretty "slick" solution. As far as "high tech" goes, the cam-corder option is cute, but no cigar. Not that it isn't high tech enuf either.
Seems like you boys and your tax-payer paid for toys have no real inderstanding of how to apply this technology in the real world where there is a budget you have to meet.
I have NEVER run the video through "an enhancement cycle", probably a spin cycle, BUT I WOULD NEVER BE CAUGHT DEAD IN AN ENHANCEMENT CYCLE.
Most body shops would NEVER under-tint either.
And if you continue to use language like PCA, DIMPLE and DEM GIS, I will have to report you.
1/30/95
14-4 unfortunately, some of the responses to this question were accidentally
deleted. 2/ 2/95bruce chapman
14-5 One deleted response suggested (1) using a blue filter and panchromatic film on auto-exposure cameras, so as not to waste emulsion grains on non-penetrating wavelengths, (2) sizing sediment particles and measuring adsorption with a spectrophotometer, so as to rationally find a penetration window, (3) having idled Navy anti-submarine planes tow sonar devices, reconstructing empty river from cross sections. Barge people needed water depth beyond 9' provided by Coast Guard. 2/ 6/95
QUESTION20
20-1 This is one of the areas that responses were accidentally deleted. I will
just restate here that there are really just 9 channels
that are recorded by sirc/X-SAR. Each quad pol frequency takes 10 bytes
per pixel (see the decompression
software manual for more details). Also, H and V just refer to the
transmit and receive polarization of each channel. 2/ 2/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
20-2 To amplify Bruce's response for those too lazy to read the manual- the two sir-c bands (L and C) and the 3 AIRSAR bands are often collected in a "polarimetric" mode. This is done by transmitting H and V and receiving all four of the possible combinations (HH, VV, HV, VH), sometimes called "quad-pol". A few years ago, we realized that if we carefully recorded the phase as well as the more traditional amplitude of the returned waves, we could combine the four linear polarizations into any other polarization: eg. linear at 45 deg., circular, elliptical, etc. The term we coined was "polarimetry". We also came up with a way to compress all this information into a minimal number (10) of bytes per pixel. Thus, one needs special decompression software to view the compressed polarimetric data. Not all SIR-C data are polarimetric- it depends on the mode. Finally, X-SAR data are only VV polarization, although they are distributed as 16-bits per pixel to maximize dynamic range. They can be scaled to bytes for viewing, which Bruce has done for the various images on the home page. 2/ 2/95Tom Farr, JPL
20-3 I recall that the deleted response to Question 20 stated that SIR-C/XSAR basically had 7 channels (not 9) because of setting HV=VH, thus LHH, LHV=LVH, LVV; CHH, CHV=CVH, CVV; XVV. These channels require 22 bytes per pixel (10 each for L and C coherence matrices plus 2 for X) in the 9 channel perspective, but seemingly only 8 + 8 + 2 = 18 bytes if reduced (bytes having real and imaginary parts.
The deleted response also discussed a mix-up with the AIRSAR data, stating it had 13 channels. AIRSAR collected polarization data for P, L, C bands and had no XSAR. Thus, it seems there should be 9 or 12 channels, depending on whether JPL set PVH=PHV, LHV=LVH, and CHV=CVH. Here there should be 30 bytes per pixel of data (10 each for the Stokes matrices) in 12 channel mode but seemingly only 24 if reduced.
2/ 5/95
20-4 The fact of the matter is, any elliptical polarization state can be represented by linear combinations of left and right circular polarizations, these in turn being expandable as superpositions of orthogonal plane polarizations. Are we not back to square one? Would researchers using radar data be likely to have a priori motivation to view any particular elliptical polarization? If isotropy is found during image enhancement, at that point, it might be physically instructive to back-synthesize the polarization that optimally gives rise to the effect. 2/ 5/95
20-5 I don't understand why scaling would be used for data reduction from 16-bits to 8-bits. Uniform compression generally severely and unnecessarily truncates the image. Better to adaptively compress, taking instruction from the histogram, compressing where the data is sparsest, that is, non-uniformly strech the contrast. The following operatations don't commute : 8-bit gsRGB to 4-bit index to contrast stretch versus 8-bit gsRGB to contrast stretch to 4-bit indexed. The first histogram is badly "combed out." 2/ 5/95
20-6 Is not JPL is exhibiting a little of the 'not invented here syndrome'? Polarimetry was invented a century ago; devices to measure components (including chirality) experimentally are described in late ninteenth century optics texts. Radio astronomers have been taking phase measurements for decades in their synthetic aperature radars, while infra-red astronomers like Kemp have been using polarized emitters (white dwarfs) and crossed crystal detectors since 1969. These are both remote sensing endeavors. I see where JPL (Radio Science 29#6, pp.1409-1420, Dec 1994) also 'discovered' that Maxwell's equations are invariant under improper Lorentz transformations (a result published in 1896)! What's next -- JPL taking credit for discovering abelian gauge theories? 2/ 5/95
20-7 Just to further clarify 20-3, the radar instrument for sirc collects HH, HV,VH, and VV data. Prior to processing that
data into images, we have stored 4 channels of data per frequency. When we process the
data into images, we can store the data into two different formats : SLC (single look
complex) or MLC (multi-look complex). The SLC data stores the 4 channels of complex
data, but compresses the 4 complex values per pixel to just 10 bytes. The MLC data is averaged down, calibrated, HV=VH,
and converts the data to a common map projection, in addition to being compressed to 10 nytes per pixel. The format that the data is stored is
determined by the investigator, but most investigators prefer MLC because the files are
smaller, the data is calibrated and converted to an easy map projection, and because it still
has the phase information between the polarization channels that permits polarization
synthesis. It can't, however, be used for interferometry, because the absolute phase for
each channel is lost. 2/ 6/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
20-8 in answer to question 20-6, please remember that jpl is a big place (5,000 engineers
and scientists), and that "JPL" does not really do anything, it is the individuals
here taking the initiative to study various problems that do the work. Obviously,
no one here can take the credit for inventing polarimetry. 2/ 6/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
QUESTION19
19-1 response is missing 2/ 2/95bruce chapman
19-2 Here's an off-the-wall idea on how to bring the XSAR date up to snuff so that the SIR-C/XSAR data set better resembles AIRSAR. There could be many benefits to this in software and data processing simplicity. XSAR only collected XVV amplitude, not XHH nor phase. Idea zero is to set XHH = XVV. Idea one is to assign every pixel a constant phase of zero. Idea two is to assign instead a random phase, with the thought that this will wash out during statistical processing. Now the X band data mimics the others in a way that does no real damage post-processing. Garbage initially but tape is cheap. 2/ 5/95
19-3 The latest version of the sir-C/airsar conversion software
now converts x-SAR data to sirc "MLD" format data. 2/ 6/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
19-4 Actually, I as looking at my code, and I do not know what the conversion is
for xsar data from unsigned integers to sigma0 - does anyone out there
know how to get sigma0 from the unsigned integer values? 2/10/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
QUESTION17
17-1 the responses to this question were accidentally deleted.
We are planning on upgrading the Macsigma0 software, and are encouraging
software developers to incorporate the sirc data formats into their software
packages. 2/ 2/95bruce chapman
QUESTION16
16-1 The responses to this question were accidentally deleted.
IDL is a commercial software package from Research systems, inc. We will
be having a link to their home page soon (when it becomes available). 2/ 2/95bruce chapman
16-2 Research Systems has used written a fairly comprehensive image-processing application called ENVI in IDL. It has the similar capabilities for AIRSAR (with upgrades promised for SIR-C) that JPL theoretically offered in MacSigma0, including local Lee standard deviation convolution filtering, ability to read Stokes matrices, synthesize polarizations, and display polarization signatures. You can get this for a Power Mac in a bizarre Unix interface for only $4,475 (June 30, 1994 price). Or you could implement the radar part alone in Mathematica ($178 ed) in a couple of hours...... tom pringle/emerald imagery 2/ 5/95
16-3 Observe that MacMultiView 5.1 costs $668 from JPL/NASA (at Cosmic) and only runs on System 6. MacSigma0, according due a deleted response, will adsorb the functionality of MMV 5.1 in a version due out summer of 1995. It currently costs $234 from JPL/NASA (at Cosmic). We already bought this software once with taxes -- now here's an opportunity to buy it again! 2/ 5/95
16-4 the upgraded Macsigma0 will be on the post-flight sir-c education cd-rom. You
will not have to buy it again. 2/ 6/95
16-5 Research Systems is a good source. I have a copy of IDL downloaded off the net and compiled on a SUN. Now I use ENVI running on Xterm from my PC to load, view and process the data. Give them a call or send a note:
(303) 786-9900 or maybe : bill@rsinc.com 2/14/95
16-6 Hi, Bill. I am new to this area. I am an environemtal engineer. Radar image can be veruseful for environmental assessemnt. I have download a image file (105k) using Zmodern Binary. My question now is what software I should use to open the binary file. My Email Address is Zhang@FreeNet.Calgary.ab.ca. (Tel:403-299-4625) Thank you! 3/ 1/95Allan Zhang, Golder Associates Ltd, Zhang@FreeNet.Calgary.ab.ca
QUESTION12
12-1 the responses to this question were accidentally deleted. what I stated before,
was that at 25 meter resolution, we would have about 200 billion pixels of the
land mass of the Earth. if SIR-C imaged the entire Earth, the data volume would
be between 0.2 to 4 Terabytes. This is not an inconceivable amount of data,
and in fact, we have imaged 99% of the surface of Venus with radar, which has a
larger
land mass area than Earth. See the Magellan data at
this home
page. 2/ 2/95bruce chapman
QUESTION18
18-1 The best place to start looking is at the Planetary Data System. Try: http://stardust.jpl.nasa.gov/pds_home.html There are links to many other sources of data. Viking did not use radar to map mars, however there have been some low-resolution maps made using earth-bound radars. 2/ 2/95Tom Farr, JPL
18-2 There is a Mars Atlas that was done based on Viking data. It's a NASA publication.
I don't have the SP number handy but I'm sure you can look it up in any list of
NASA publications. 2/ 6/95Jay Trimble, JPL, jtrimble@jpljpt.jpl.nasa.gov
18-3 There is a www site with an
on-line atlas of Mars obtained from the Viking orbiters. 2/ 6/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
18-4 You might want to check out the VistaPro CDROM. IT has the complete
DEM data set for Mars and a great landscape rendering program. For both
Mac and Windows. You can buy it from Educorp in San Diego.
Contact me for for more information. 303-258-3779 3/27/95James Perdue, Rocky Mtn Digital Peeks, rmdp@csn.org
QUESTION25
25-1 As I discuss in a response to question 20, for quad pol data we can save the processed
images in two different formats: single look complex (SLC) or multilook complex (MLC).
The SLC data saves the four complex values per pixel that define the scattering matrix,
and is compressed to 10 bytes per pixel. with this data, all four received channels of
data are stored. With MLC data, cross-products of the symmetrized stokes matrix are
saved. The symmetrized stokes matrix has HV=VH. Also, the data is converted to what
we call the "ground range" projection, which is just a map projection on the ground.
the SLC data is in the natural "Slant range" projection, which is a projection that
is caused by the manner that the radar operates, and is somewhat peculiar. Also, the MLC
data is averaged (multilooked) so that each pixel is either 12.5 or 25 meter spacing. This reduces
the file size. The MLC data preserves the phase between the polarization channels,
and so polarization synthesis is possible (i.e. can synthesize ANY polarization, like right circular).
MLC data can not be used for interferometry, as the absolute phase is lost, so in that case,
SLC data is required. The data format for any given image is requested by the investigator that
has requested the data processing. 2/ 6/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
25-2 Just a further comment : you might want to look at a description
of the data formats where I talk about some of this more completely. 2/ 7/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
QUESTION22
22-1 without a solid surface to reflect radar waves, it would be difficult to interpret the data.
You would need to have a high power transmitter, even if it was orbiting jupiter.
I am not aware of any attempts to detect Jupiter from ground based radar antennas, but
I would not be surprised if someone had attempted it 2/ 6/95
22-2 I believe he is asking about the dielectric constant of the Jovian atmosphere as a function of depth. Radar penetration, based on the 9000 watt Shuttle instrument, seems nil by the time the dielecric constant reaches 3 or 4., which is why water at 87 isn't seen at depth. I would not be surprised if detailed models of Jupiter exist, along the lines of model stellar atmospheres, because there was a lot of interest once in how close Jupiter came to being a binary companion of the sun. Thus, the interpretation of radar data is its comparison to reflectance predicted by the model. The tricky part is how to refine the model if it doesn't agree with the data.. Interferometric data could conceivably be used to probe the depth of turbulent structures. While isotropy is present, It seems that polarized radar is at too long a wavelength to detect it. 2/18/95
22-3 Some of the earliest planetary radar astronomy work was ground based and signals were bounced off the planets. I have not checked the literature, but I know that Venus was probed this way early on, so maybe someone studied Jupiter. try look at the older radar astronomy literature. Also, due to the nature and chemical composition of the Jovian atmosphere, the penetration in to the atmosphere may be very frequency dependent due to absorption by various molecular species. More fun! 3/ 9/95Sam Gasster, Then Aerospace Corporation, gasster@aero.org
QUESTION26
26-1 The Science team members and their activities
are listed here. This document will indicate what the members of the science team
are studying. In addition, you can respond to our outreach program,
and we will try to either process data for you, or send you data that has already
been processed. There is a picture of ubar from SRL-1.
Eventually, all the precision data products will be available at the Eros data center, but
the procedures for that are still being worked out. Also, it will take us years to
process all the data from the two missions. However, most of the data from flight one
is now available at the Eros data center, there is a link to that location here 2/ 7/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
QUESTION27
27-1 There is not yet an AIRSAR home page, but soon there will be. I will be sure
to announce it when it is on-line, and to put links to it. 2/ 9/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
QUESTION28
28-1 I assume that you have gotten the data from the Eros data center, and
have downloaded on of the .IMG image segments. This file is what photoshop
would call in the "raw" format. So, open photoshop, pull down the file
menu, select "open as", change the file format to "raw", enter the
name of the file. The next window will ask about the dimensions of the
file : enter the height and width of the image (this is given at the page
that you retrieved the .IMG file. It will be 2000 in width, as all of the
segments are 2000 in width.) There is no header in this file. photoshop
should then be able to open the file and display it. write back if this
does not work... 2/ 9/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
28-2 In Photoshop, after Open, click show all files. Locate .img file and double click. There is no need to enter width and height -- Photoshop knows these already. This is a grayscale so there are no issues with band interleaving.
For NIH-Image 1.57 freeware , select Import rather than Open. Choose Custom and edit to width and height (e.g., 2000 x 1266) and the file will open. tom@emerald 2/19/95
QUESTION32
32-1 1 - we currently have the SIR-C/X-SAR science team members
listed, with their research interests and addresses, but we have not had time
to add more than that yet...
2 - Because the Sample data sets are so large, it is not very feasible at this
time to put the data on-line.
3 - We have put a SAR reference list on-line, though it
is admittedly not complete, it is the best that we have right now.
2/15/95
bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
32-2 Nice job on expanding the SAR reference list -- last time I looked it only had one entry! I wonder if some of the papers could be put online, or at least the abstracts, or links if the journals are ftp sites -- one hopes that some of the papers are still around, electronically speaking, and wouldn't have to be OCRd in. I'm at a large research university and frankly, no one has ever heard of some of these journals. 3/19/95
QUESTION31
31-1 The captions to the images at the jplinfo site unfortunately do not include datatake id
and segment number. However, if you wish to request a precision data product from
areas corresponding to these images, just indicate the lat/lon, and that it is
an area shown in an image at the jplinfo site, and we will look up the rest. 2/15/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
QUESTION34
34-1 You might want to look at
the response to question 8. There, Diane Evans replies to this question.
The SIR-C Survey data is already on CD-ROM, for information,
click here. In a few months, we should be distributing the SIR-C post flight
education CD-ROM. This cd-rom will have some images from sirc. There is
currently no plans to distribute other images or data by cd-rom, though some
commercial companies have expressed an interest in some. I will let everyone
know here at the imaging radar home page. 2/16/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
34-2 Since Diane's response, there has been a lot of activity involved in definition of what a third flight of SIR-C/X-SAR could do. One of the options being explored is to add a boom about 30 m long with a C-band and maybe an X-band antenna on it. This would allow single-pass interferometry to be accomplished which could be used to produce a digital topographic map of the entire earth (between 60 deg N and S latitudes) at about 80 m horizontal resolution. As Diane said, decisions will be made in the next month or two whether this will be pursued. 2/17/95Tom Farr, JPL, tom.farr@jpl.nasa.gov
34-3 In one month I will publish a CD-ROM called "Earth Exploratorium". It contains
12000 visual images for SRL-1 and over 40 SIR-C/X-SAR images in a
very unique navigational interface with lots of search capabilities.
For more info, send e-mail to rmdp@csn.org.
Newt Perdue, Rocky Mountain Digital Peeks 303-258-3779, only $39. 3/27/95
QUESTION33
33-1 You're not very specific on your "project", but Lidars have mostly been used as altimeters (see refs below). also, there was some work a while back on looking at the reflectance and fluorescence of the ground with a CO2 laser. sorry, i don't have the refs for that handy.
Bufton, J.L., J.B. Garvin, J.F. Cavanaugh, L. Ramos-Izquierdo, T. Clem, W.B. Krabill, 1991, Airborne LIDAR for profiling of surface topography, Optical Eng., v. 30, p. 72-78.
Harding, D.J., J.L. Bufton, J.J. Frawley, 1994a, Laser altimetry of terrestrial topography: Vertical accuracy as a function of surface slope, roughness, and cloud cover, in press, IEEE Trans. Geosci. Rem. Sens.
2/17/95Tom Farr, JPL
QUESTION36
36-1 Put in a link to current versions of Netscape and Mosaic. I don't see a further need to support obsolete browsers. 2/18/95
36-2 You should be able to configure the font selection of your
browser yourself. The fixed (a.k.a. monospaced) font is the
one you'd want to change. Look under Preferences...
If it's not there, then there's nothing you can do except
get a newer browser (I'm pretty sure recent Mac Mosaics support
font selection...) 3/21/95
QUESTION37
37-1 Would this not require platform-dependent compressions of each file to get beyond .gif? 2/18/95
37-2 Most of the images are smaller than 400K. I try to keep the images as small as possible
and still retain their information content. 2/20/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
QUESTION38
38-1 There are two options that readily come to mind using JPL developed software (some
commercial software companies now have software to read AIRSAR format data).
1. get the sir-c data decompression and conversion software. the conversion software
can convert the AIRSAR data to sirc format, and then the decompression software can
synthesize any polarization.
2. There is a program called Macsigma0 that can read and display and allows simple
analysis of AIRSAR data. We will be coming out with a new version of this software soon also. I will keep visitors to the
imaging radar home page updated as to the status of this.
2/21/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
QUESTION35
35-1 the .IMG survey image files are just raw byte image files. In this case, the .IMG does not refer to ERDAS' Imagine image format, which also has a .IMG extension. Most any image processing program can read the survey images as raw bytes, using the dimension information associated with the survey product. 2/21/95Tom Farr, tom.farr@jpl.nasa.gov
35-2 If you are working with ERDAS-IMAGINE software you can import this king of
format in the import-expot option using the "generic bynary data" option.
You only need to know the number of lines, samples and header bytes, and
you can know all this information from the header of your images. 3/25/95Alvaro Marquez, Complutense University, Madrid, Spain, anguita@eucmvx.sim.ucm.es
QUESTION39
39-1 Good idea! We've been thinking about doing that and will get such a list posted sometime this week. The list will contain the DT number, site name, scene center GMT and scene center latitude and longitude, along with some other information. This list can be used in conjunction with the posted survey data to get a "preview" of the precision processed scene. Keep your eyes out for this posting! 2/27/95ellen o'leary, jpl, ellen.oleary@jpl.nasa.gov
QUESTION40
40-1 I got the following information from the EROS Data center SIR-C survey image
home page at
this location:
IMDISP: This software is a general-purpose image display program. It supports EGA, VGA and numerous
super-VGA display boards. This program is available and free to have a copy. For further information, contact
Mike Martin at (818)306- 6038 (JPLDPS::MMA.RTIN on SPAN)
I think his email address is mmartin@jplpds.jpl.nasa.gov
Maybe someone else knows where to get this software on-line?
3/ 2/95Bruce Chapman, jpl, bruce.chapman@jpl.nasa.gov
40-2 I just recently discovered that this program for PC type computers is on the
pre-flight SIR-C education CD-ROM 3/14/95bruce chapman, jpl, bruce.chapman@jpl.nasa.gov
QUESTION41
41-1 You must use ftp, not telnet, to kahn in order to get the raven s/w. Then
login as guest and enter the password. Next, cd over to pub/raven. Note,
RAVEN for IDL 3.6 will be available this week. 3/ 6/95Sharon Okonek, JPL, sharon.okonek@jpl.nasa.gov
41-2 In addition to response 41-1, I should mention that in order to obtain RAVEN
and any other SIR-C software, you must join our Outreach program. This will
involve signing a license agreement (amongst some other things). For more
info, go to the outreach info page available
through the JPL Imaging Radar Home Page. 3/ 6/95Sharon Okonek, JPL
41-3 Ellen O'Leary's exact email address is Ellen.F.O'Leary@ccmail.jpl.nasa.gov JPL has an X.500 Information Service where you can look up the address of JPL employees and contractors. To querry this database, finger employee-name@jpl.nasa.gov. Since Ellen is the only O'Leary on lab, you could also send email to the infoserver address, where it would be forwarded to the proper location. In this case, you could send email to oleary@jpl.nasa.gov. 3/13/95Tim Fogarty, JPL, fogarty@sir-c.jpl.nasa.gov
QUESTION43
43-1 first response. see if it works. 3/ 6/95sharon , jpl, sharon@jpl
43-2 Second response. 3/ 6/95
43-3
Terminal Doppler Weather Radar: TDWR
All of these have TDWR data:
- Aviation Weather Development Lab
- oratory (AWDL) was established by the Federal Aviation Administration (FAA) to support weather projects in the evolving U.S. National Airspace System. Vast amounts of data from new weather sensing systems such as Next Generation Weather Radars ...
--- [760] http://http.rap.ucar.edu/awdl.html (7K)
- Stormscale Research and Applications Division (SRAD)
- Mike Eilts, Manager (405) 366-0414 . Personnel as of 4 October 1994-- . Mike Eilts, Manager (405) 366-0414 . Kelly Lynn, Secretary (405) 366-0402 . Susan Cobb, Graphics Consultant . Subdivision information: . Scientific Advisory Panel ...
--- [651] http://www.nssl.uoknor.edu/srad/srad.html (3K)
- MIT Radar Data Archive
- This document describes the field programs in which the MIT radars have participated over the last twenty years. . Contents: . Introduction . Field Program Objectives . Storage Media . Radar Platforms . Processing and Software . ...
--- [646] http://graupel.mit.edu/Inventory.html (39K)
- NSSL/SWAT Home Page
- SWAT . Mission Statement . The mission of the Severe Weather Warning Applications and Technology Transfer (SWAT) team is to develop severe weather warning applications and transfer them to users to enhance their capability to warn of severe ...
--- [630] http://www.nssl.uoknor.edu/srad/swat.html (3K)
- Gallery: Gust fronts et als.
- Gust fronts, thin lines, microbursts, sea breezes (updated 10/27/94) . A gust front in New Mexico: reflectivity and velocity (44K, 54K) . A crisp, clear gust front from a distant (off scope) MCS to the east topped the Sandia Mountains and at
--- [625] look here too
- Other Weather Radar Web Sites
- Other interesting Web Pages on Weather Radar: . The University of Wisconsin puts out a US IR/Radar Composite image (usually ~ 32K) and movie (usually ~850K). A higher resolution image may be found at NASA/MSFC. You can also find current refs at
--- MIT
-
brought to you by tom @ emerald
3/29/95
43-4
For ASR9:
- MIT Radar Data Archive
- This document describes the field programs in which the MIT radars have participated over the last twenty years. . Contents: . Introduction . Field Program Objectives . Storage Media . Radar Platforms . Processing and Software . ...
--- [767] http://graupel.mit.edu/Inventory.html (39K)
