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Venus Express: One Year in Orbit, Symposium at the 2007 EGU General Assembly
Guest_AlexBlackwell_*
post Jan 3 2007, 07:37 PM
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Forwarding an email that was sent out today by Dmitri Titov, Venus Express PI. Cross reference with this UMSF thread.

QUOTE
Dear Colleagues,

the General Assembly of the European Geophysical Union (EGU) will be held on April 15-20, 2007 in Vienna, Austria. The Symposium PS 2.1 "Venus Express: one year in orbit", included in the science Programme, will be focused on presentation and discussion of the results obtained during the first year of the orbital mission. Please find the description of the Symposium at the end of the e-mail and visit the EGU Web site: http://meetings.copernicus.org/egu2007/ for more details about the Assembly.

We would like to encourage you to take part in the Symposium and to submit contributed abstracts. Please note that the deadline for abstracts submission is January 15, 2007.

Best regards

Dima Titov and Hakan Svedhem,
The Conveners
_________________________________________________
On April 11, 2006 Venus Express-the first European satellite at Venus- was inserted in orbit around the planet and began collecting data. The results of the first year of observations will be presented at the Symposium. The Programme will consist of solicited talks focused on the Venus Express observations and contributed presentations of the preliminary data analysis. The contributions related to the physics of Venus atmosphere, its plasma environment and the surface and based on the analysis of the data from Venus Express and earlier missions, theoretical studies and numerical modelling are highly welcome. Perspectives of the future Venus exploration will be discussed.

Convener : D. Titov (Max Planck Institute for Solar System Research, Germany) Co-convener : H. Svedhem (ESA/ESTEC, The Netherlands)
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ollopa
post Jan 9 2007, 02:25 PM
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This discussion is more noise than information. Can I suggest Nils Muller's astonishing extraction algorithm as a way of getting at what lies beneath? Anyone who wonders why VEX has taken so long to release product should read the Mueller paper (summary below). This young man and his colleagues have slaved for month after month to extract surface emissivity data out of the scrambled VIRTIS data. Their first "picture" (yes, one) was displayed at AGU last month. Mueller was the proudest planetary researcher I have ever met, bar none. Does he care he's not a daily POD?

ESA's non-core budget was evicerated several years ago to repay (IIRC) seven BILLION euro to industry. If that debt of honour was not repayed there would have been no ESA. P.R. was a major victim. Vote now: PODs or missions?

Individual MEX PI's such as Bibring and Neukem use their own precious time and budgets to turn up at virtually every planetary science meeting around the globe. I have found them willing to share information at a level that matches or exceeds the undoubted openness of their U.S. colleagues.

I am not associated with ESA, but I believe their public outreach staff do a very credible job in often straitened circumstances. My in-box tells me that ESA's press office has issued seven press releases in the first week of 2007 - four on Friday alone. I am aware that ESA is currently exploring novel alternative ways of structuring its public outreach with the help of member governments, but there's a limit to what you can do in-house if the-powers-that-be insist on putting research ahead of PODs.



P42A-07

Algorithm for Extraction of Surface Emissivity in the Context of VIRTIS on Venus Express

* Mueller, N (nils.mueller@dlr.de) , DLR Institute for Planetary Research, Rutherfordstr. 2, Berlin, 12489 Germany
Jorn, H (joern.helbert@dlr.de) , DLR Institute for Planetary Research, Rutherfordstr. 2, Berlin, 12489 Germany
Hashimoto, G (george@kobe-u.ac.jp) , Graduate School of Science and Technology, Kobe University, Nada-ku, Kobe, 657-8501 Japan
Marinangeli, L (luciam@irsps.unich.it) , IRSPS, Universita d Annunzio, Viale Pindaro, 42, Pescara, 65127 Italy
Piccioni, G (piccioni@rm.iasf.cnr.it) , INAF - IASF Roma, Via del Fosso del Cavaliere 100, Roma, 00133
Drossart, P (Pierre.Drossart@obspm.fr) , LESIA - Observatoire de Paris, 61 avenue de l observatoire, Paris, 75014 France

Venus nightside multispectral images aquired by VIRTIS contain information of surface emissivity at wavelengths close to 1 micron. This information is relayed by thermal emissions of the surface escaping to space through the NIR spectral 'windows' in the atmosphere. On its way through the atmosphere the thermal radiation is modified by scattering and absorption by clouds. Variations in the optical thickness of the clouds modulate the spatial distribution of upwelling radiation. Multiple reflections between surface and clouds generally wash out image contrast from surface emissivity. We present an algorithm to extract surface emissivities by separating atmospheric influences from the images inside the spectral windows at 1.02, 1.10 and 1.18 micron. The necessary processing steps detailed are: 1) Removal of scattered sunlight 2) Binning of appropriate images inside the window spectral ranges 3) Correction of limb darkening 4) Removal of contrast due to attenuation by clouds 5) Removal of contrast due to surface temperature 6) Correction for multiple cloud-surface-reflections For a first quick guess on general trends of emissivity with respect to geological circumstances this algorithm is applied with several simplifications and ad-hoc assumptions. This simple model assumes the atmosphere of Venus to be one horizontally homogenous layer with spatial variation of transmittance allowing for direct inversion of the data. For an improved estimation of surface emissivity tabulated results from previous forward modeling of radiative transfer are used for steps 2) to 6). With this approach the accuracy of a detailed modeling of the atmosphere of Venus is combined with the speed and traceability of the step-by-step inversion of radiance data using the simplified model.
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djellison
post Jan 9 2007, 03:34 PM
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QUOTE (ollopa @ Jan 9 2007, 02:25 PM) *
This young man and his colleagues have slaved for month after month to extract surface emissivity data out of the scrambled VIRTIS data. Their first "picture" (yes, one) was displayed at AGU last month.


Not true.

Oct. 4, 2006 | 09:54 PDT | 16:54 UTC
http://www.planetary.org/blog/article/00000714
Nils Muller then presenting a brief look at some science being conducted by the VIRTIS instrument onboard VEX to try to pull data out from the surface. About 95% of the data in the 990-1050 nm range comes from the surface and this reduces to no surface data in the 1250-1320 nm. BUT -- the 990-1050 range still has an input from the clouds. So, using clever maths, Muller basically stacks a few images from the 990-1050 range, and subtracts the influence of the clouds in the longer wavelengths to hopefully get a temperature map of the surface. Due to blurring by the atmosphere, the resolution of this data is only around 100 kilometres per pixel, however he was able to present some images that showed a variety of surface temperatures from around 720 to 740 Kelvin from data taken out of a mosaic of images collected on the 112 orbit. This data actually quite closely matches the altitude maps of Venus collected by the Magellan mission. So, if it matches the Magellan altitude data so well, what's the point in going to all that trouble? The simple answer -- Volcanic activity. Your average Venusian volcanic lava flow is expected to be perhaps 1000-1500 Kelvin and cover many hundreds of square kilometres, so it should be visible in these 100 kilometre resolution thermal maps. Hopefully, if there is any active volcanic activity going on down under the clouds, then this technique should be able to find it as a change of a more than 5 deg Kelvin in his thermal maps.

I wrote the words, I saw the pictures.

Turning up at a planetary science meeting and a cohesive broad education and outreach program are not the same thing. I don't blame the scientists per se - but the public awareness of planetary exploration by ESA is a disgrace. Fact. No one can pretend it's at an acceptable level.

From the enthusiasts perspective - a few key issues that I still consider unacceptable.

HRSC's lack of map projection for all channels and refusal to release DEM's to the PSA/PDS given that some of this has been sat on hard drives at ESA for 3 years and it is generated in near real time.

Smart 1 data......six month chunks six moths in arrears I was told at IAC. To date - nothing.

Huygens data - DISR and SSP still not published onto the PSA or PDS - despite promises of '12 months' then August, then October on the PSA and PDS.

ESA's outreach and data publishing efforts are sub-par. As a tax payer in Europe I expect and deserve more.

Doug
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ollopa
post Jan 9 2007, 04:23 PM
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[quote name='djellison' date='Jan 9 2007, 03:34 PM' post='79831']
Not true.


Sorry, Doug, but I don't understand what's not true? They *did* work for months and they *did* show just one picture at AGU. Maybe they showed the same pic or an earlier iteration at IAF, fine. My point is the effort it took to get to one POD.

As for raw data releases, that's beyond the remit of ESA's public outreach.
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Posts in this topic
- AlexBlackwell   Venus Express: One Year in Orbit   Jan 3 2007, 07:37 PM
- - JRehling   [...]   Jan 4 2007, 06:17 PM
|- - Littlebit   QUOTE (JRehling @ Jan 4 2007, 11:17 AM) T...   Jan 4 2007, 07:13 PM
- - Phil Stooke   "VE is a failed mission." On the contra...   Jan 4 2007, 07:40 PM
|- - AlexBlackwell   QUOTE (Phil Stooke @ Jan 4 2007, 09:40 AM...   Jan 4 2007, 08:16 PM
|- - helvick   True it is only a PR failure and apart from the PF...   Jan 4 2007, 08:31 PM
- - djellison   A PR failure - but not a failed mission by any str...   Jan 4 2007, 08:09 PM
|- - Littlebit   QUOTE (djellison @ Jan 4 2007, 01:09 PM) ...   Jan 4 2007, 08:55 PM
- - djellison   Oh - we all know that ESA is just utterly utterly ...   Jan 4 2007, 08:47 PM
- - djellison   Yes - but there IS someone to observe the event - ...   Jan 4 2007, 08:59 PM
|- - Bob Shaw   I think that in the US the space community long ag...   Jan 4 2007, 10:33 PM
|- - JRehling   [...]   Jan 5 2007, 12:07 AM
|- - dvandorn   QUOTE (JRehling @ Jan 4 2007, 07:07 PM) I...   Jan 5 2007, 12:20 AM
|- - djellison   QUOTE (dvandorn @ Jan 5 2007, 12:20 AM) C...   Jan 5 2007, 12:26 AM
||- - JonClarke   I have said this before and I am going to say this...   Jan 5 2007, 09:51 PM
||- - Bob Shaw   QUOTE (JonClarke @ Jan 5 2007, 09:51 PM) ...   Jan 5 2007, 10:07 PM
||- - AlexBlackwell   QUOTE (JonClarke @ Jan 5 2007, 11:51 AM) ...   Jan 5 2007, 10:25 PM
||- - djellison   QUOTE (JonClarke @ Jan 5 2007, 09:51 PM) ...   Jan 6 2007, 12:07 AM
||- - JRehling   QUOTE (JonClarke @ Jan 5 2007, 01:51 PM) ...   Jan 7 2007, 07:32 PM
|- - Bob Shaw   QUOTE (dvandorn @ Jan 5 2007, 12:20 AM) T...   Jan 5 2007, 12:32 AM
- - JTN   Since this old chestnut has come up again: I thoug...   Jan 4 2007, 10:30 PM
- - remcook   A question: who does all the outreach for the MERs...   Jan 5 2007, 04:42 PM
- - nprev   Doug & admins, please move this post as approp...   Jan 8 2007, 03:29 AM
- - ollopa   This discussion is more noise than information. C...   Jan 9 2007, 02:25 PM
|- - ustrax   QUOTE (ollopa @ Jan 9 2007, 02:25 PM) Thi...   Jan 9 2007, 02:52 PM
||- - 4th rock from the sun   Let me dream a little, but part of the solution to...   Jan 9 2007, 03:36 PM
|- - djellison   QUOTE (ollopa @ Jan 9 2007, 02:25 PM) Thi...   Jan 9 2007, 03:34 PM
||- - ollopa   [quote name='djellison' date='Jan 9 20...   Jan 9 2007, 04:23 PM
|- - JRehling   [...]   Jan 9 2007, 05:38 PM
|- - ustrax   QUOTE (JRehling @ Jan 9 2007, 05:38 PM) B...   Jan 9 2007, 05:49 PM
|- - djellison   QUOTE (ustrax @ Jan 9 2007, 05:49 PM) The...   Jan 9 2007, 07:21 PM
- - djellison   Outside the remit of outreach - but still a job it...   Jan 9 2007, 05:05 PM
- - slinted   I know there's no way of knowing how this woul...   Jan 14 2007, 07:59 AM
- - J.J.   I agree with others who say that the differences b...   Jan 14 2007, 07:58 PM
|- - tedstryk   QUOTE (J.J. @ Jan 14 2007, 07:58 PM) To b...   Jan 14 2007, 09:05 PM
|- - Bob Shaw   QUOTE (J.J. @ Jan 14 2007, 07:58 PM) To b...   Jan 15 2007, 09:35 PM
- - edstrick   "have sites that look like they were designed...   Jan 15 2007, 11:29 AM
- - remcook   QUOTE Well, with Giotto and MEx there have been is...   Jan 15 2007, 03:01 PM
- - dvandorn   I'm unsure whether this observation should go ...   Jan 15 2007, 04:07 PM
|- - tedstryk   QUOTE (dvandorn @ Jan 15 2007, 04:07 PM) ...   Jan 15 2007, 04:31 PM
- - AlexBlackwell   The abstracts for this session are now online. Ch...   Jan 30 2007, 12:57 AM
- - ustrax   Does anyone need a job?... A lot more here.   Feb 14 2007, 12:34 PM


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