Difference between revisions of "August 5, 2004"

From LPOD
Jump to: navigation, search
 
(7 intermediate revisions by the same user not shown)
Line 1: Line 1:
 
__NOTOC__
 
__NOTOC__
 
=Ranger Cratering=
 
=Ranger Cratering=
 +
<!-- Start of content -->
 
<br>
 
<br>
 
<table width="85%"  border="0" align="center" cellpadding="6" cellspacing="2">
 
<table width="85%"  border="0" align="center" cellpadding="6" cellspacing="2">
Line 15: Line 16:
 
<table width="100%"  border="0" cellpadding="8">
 
<table width="100%"  border="0" cellpadding="8">
 
<tr>
 
<tr>
<td><div align="center" span class="main_sm">Image Credit: [mailto:pjstooke@uwo.ca Phil Stooke]</div></td>
+
<td><div align="center"><p>Image Credit: [mailto:pjstooke@uwo.ca Phil Stooke]</p></div></td>
 
</tr>   
 
</tr>   
 
</table>   
 
</table>   
Line 22: Line 23:
 
<p class="story" align="center"><b>Ranger Cratering</b></p>
 
<p class="story" align="center"><b>Ranger Cratering</b></p>
 
<p class="story" align="left">
 
<p class="story" align="left">
Identification of craters made by spacecraft impact on the Moon is valuable because it permits calibration of impact energy and crater size relations. And its fun. The camera failure on the otherwise successful [http://www.lpod.org/archive/2004/07/LPOD-2004-07-29.htm Ranger 6]  meant that it's exact crash point is unknown. Now this mosaic of Clementine Long Wavelength Infrared images (right image) may solve that mystery. But first, here is some context. Image C is a one degree square from the [http://www.lpod.org/archive/2004/03/LPOD-2004-03-27.htm LTO]  of the area (LTO60B4), here made of high sun Apollo images.  Image D is the same image eaxctly, but overlaid with a mosaic of the Clementine LWIR images. LWIR doesn't give full coverage so there are gaps through which the LTO can be seen. The proposed Ranger 6 impact point is a unique dark spot in LWIR, but just one of many bright spots in the visible. This small triangular dark spot is only 7 km northwest of the tracking prediction for the Ranger 6 impact point. I propose that this is the Ranger 6 impact ejecta deposit. I looked at the Consolidated Lunar Atlas to see if the spot is 'new' - but alas, the CLA image of the area was taken after the impact!  Also, the spot is only barely visible, if at all. The large crater seen in the Clementine view is shown on the [http://www.lpod.org/archive/2004/06/LPOD-2004-06-28.htm LAC]  of the area and is visible in the CLA. This image was prepared as an illustration for my forthcoming atlas of lunar exploration.
+
Identification of craters made by spacecraft impact on the Moon is valuable because it permits calibration of impact energy and crater size relations. And its fun. The camera failure on the otherwise successful [[July_29,_2004|Ranger 6]]  meant that it's exact crash point is unknown. Now this mosaic of Clementine Long Wavelength Infrared images (right image) may solve that mystery. But first, here is some context. Image C is a one degree square from the [[March_27,_2004|LTO]]  of the area (LTO60B4), here made of high sun Apollo images.  Image D is the same image eaxctly, but overlaid with a mosaic of the Clementine LWIR images. LWIR doesn't give full coverage so there are gaps through which the LTO can be seen. The proposed Ranger 6 impact point is a unique dark spot in LWIR, but just one of many bright spots in the visible. This small triangular dark spot is only 7 km northwest of the tracking prediction for the Ranger 6 impact point. I propose that this is the Ranger 6 impact ejecta deposit. I looked at the Consolidated Lunar Atlas to see if the spot is 'new' - but alas, the CLA image of the area was taken after the impact!  Also, the spot is only barely visible, if at all. The large crater seen in the Clementine view is shown on the [[June_28,_2004|LAC]]  of the area and is visible in the CLA. This image was prepared as an illustration for my forthcoming atlas of lunar exploration.</p>
 
<blockquote>
 
<blockquote>
 
<p align="right"> &#8212; [mailto:pjstooke@uwo.ca Phil Stooke ]</p>
 
<p align="right"> &#8212; [mailto:pjstooke@uwo.ca Phil Stooke ]</p>
Line 30: Line 31:
 
<p><b>Related Links:</b> <br>
 
<p><b>Related Links:</b> <br>
 
[http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1994-004A&ex=3 Clementine LWIR] </p>
 
[http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1994-004A&ex=3 Clementine LWIR] </p>
<p><b>Tomorrow's LPOD:</b> Lunar Resort</p>
+
<p><b>Yesterday's LPOD:</b> [[August 4, 2004|A New Way to Image the Moon]] </p>
 +
<p><b>Tomorrow's LPOD:</b> [[August 6, 2004|Moon Resort]] </p>
 
</tr>
 
</tr>
 
</table>
 
</table>
Line 41: Line 43:
 
<td><p align="center" class="main_titles"><b>Author & Editor:</b><br>
 
<td><p align="center" class="main_titles"><b>Author & Editor:</b><br>
 
[mailto:tychocrater@yahoo.com Charles A. Wood]</p>
 
[mailto:tychocrater@yahoo.com Charles A. Wood]</p>
<p align="center" class="main_titles"><b>Technical Consultant:</b><br>
+
<!-- Cleanup of credits -->
[mailto:anthony@perseus.gr Anthony Ayiomamitis]</p>
+
<!-- Cleanup of credits -->
<p align="center" class="main_titles"><b>A service of:</b><br>
+
<!-- Cleanup of credits -->
[http://www.observingthesky.org/ ObservingTheSky.Org]</p>
+
<!-- Cleanup of credits -->
<p align="center" class="main_titles"><b>Visit these other PODs:</b> <br>
+
<!-- Cleanup of credits -->
[http://antwrp.gsfc.nasa.gov/apod/astropix.html Astronomy] | [http://www.msss.com/ Mars] | [http://epod.usra.edu/ Earth]</p>
+
<!-- Cleanup of credits -->
 +
<!-- Cleanup of credits -->
 
</td>
 
</td>
 
</tr>
 
</tr>
 
</table>
 
</table>
 
<p>&nbsp;</p>
 
<p>&nbsp;</p>
----
+
<!-- End of content -->
===COMMENTS?===
+
{{wiki/ArticleFooter}}
Register, and click on the <b>Discussion</b> tab at the top of the page.
 

Latest revision as of 18:23, 7 February 2015

Ranger Cratering


LPOD-2004-08-05.jpeg

Image Credit: Phil Stooke


Ranger Cratering

Identification of craters made by spacecraft impact on the Moon is valuable because it permits calibration of impact energy and crater size relations. And its fun. The camera failure on the otherwise successful Ranger 6 meant that it's exact crash point is unknown. Now this mosaic of Clementine Long Wavelength Infrared images (right image) may solve that mystery. But first, here is some context. Image C is a one degree square from the LTO of the area (LTO60B4), here made of high sun Apollo images. Image D is the same image eaxctly, but overlaid with a mosaic of the Clementine LWIR images. LWIR doesn't give full coverage so there are gaps through which the LTO can be seen. The proposed Ranger 6 impact point is a unique dark spot in LWIR, but just one of many bright spots in the visible. This small triangular dark spot is only 7 km northwest of the tracking prediction for the Ranger 6 impact point. I propose that this is the Ranger 6 impact ejecta deposit. I looked at the Consolidated Lunar Atlas to see if the spot is 'new' - but alas, the CLA image of the area was taken after the impact! Also, the spot is only barely visible, if at all. The large crater seen in the Clementine view is shown on the LAC of the area and is visible in the CLA. This image was prepared as an illustration for my forthcoming atlas of lunar exploration.

Phil Stooke

Technical Details:
Clementine LWIR images are small and dreadfully noisy. Nevertheless any amateur can work with them. NASA's Planetary Image Atlas allows them to be selected from a given area. I open the resulting GIF images in Photoshop, convert them to grayscale, and do some preliminary noise removal and contrast enhancement. Then those images are stacked and averaged. It is necessary to collect numerous images from the orbit you want to work on and stack enough of them that real landscape features are averaged out, leaving only the noise. This 'average' image can then be subtracted from the original frames. The results are good - since LWIR measures temperature, sunlit slopes are warm and look bright, shadier slopes are cool and look dark. The image looks like a regular photo with shading, even near the equator where Clementine visible images look very bland.

Related Links:
Clementine LWIR

Yesterday's LPOD: A New Way to Image the Moon

Tomorrow's LPOD: Moon Resort



Author & Editor:
Charles A. Wood

 


COMMENTS?

Register, Log in, and join in the comments.