Author Topic: TLP Project - Lunar Swirls  (Read 20433 times)

Geoff

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TLP Project - Lunar Swirls
« on: July 16, 2010, 06:54:37 pm »
Background: See this thread for background on this project: Moon Zoo Challenge

Location: Site 1: Reiner Gamma (56.8W, ~14N) [Latitude: 14  Longitude: -56.8].
 Site 2: Mare Ingenii (166.1E, 36.0S) [Latitude: -36.0  Longitude: 166.1].
 and other sites e.g. Mare Marginis.

Images: Reiner Gamma swirl - M117874527ME
 Butterfly swirl - M103439292MC

Discovery: Lunar Orbiter era and possibly earlier

Description: Light and dark adjacent broad curves, often described as swirls. Do not get confused with radial crater rays! So far these are seen on dark mare with no discernable difference in surface texture when examined close up. To date all known swirls have been seen over large areas and not small km size regions. These are best seen in images with little shadow.

Interest: Each swirl site is believed to sit over a local magnetic field that sets up a mini- magnetosphere, strong enough to deflect at least some solar wind particles and reduce space weathering of the soil. The latest theory is that electric fields above the lunar surface help to sweep the surface clean of charged dust particles. It would be interesting to identify new candidate sites and to see what different sizes they come in, where they are located, are any in highland areas, and also to monitor them at different times to see if changes in dust deposits can be observed.
Two of the swirls on the far side of the Moon are directly opposite the centres of two large near side impact basins, Mare Imbrium and Mare Orientale. So there appears to be some connection with a large impact causing a swirl to appear on the opposite side of the Moon.

External References:

NASA Science News; Lunar Swirls

The Lunar Swirls - PDF document

Varieties of Lunar Swirls - PDF document


Reiner Gamma swirl (7.4 N, 300.9 E)
(LROC WAC M114342152CE)
~
“Butterfly swirl” in Mare Ingenii (directly opposite Mare Imbrium).
(LROC WAC M103439292MC)



If you find what you think is a lunar swirl please post it in this thread.
Don't forget a picture, the strip reference (LROC / NAC reference) and the approximate latitude and longitude.
Good luck!  :)
« Last Edit: October 25, 2011, 09:14:55 am by Geoff »

Tom128

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Re: TLP Project - Lunar Swirls
« Reply #1 on: July 18, 2010, 04:10:05 am »
Suspect swirls in white debris right side of photograph near edge of this large crater.



# ID: AMZ20000te
# Latitude: 23.8989°
# Longitude: 312.985°

More swirl-like formations to the right of photo above- left side of photo below.



# ID: AMZ20000uc
# Latitude: 23.8989°
# Longitude: 313.052°



« Last Edit: July 18, 2010, 04:15:48 am by Tom128 »

Thomas J

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Re: TLP Project - Lunar Swirls
« Reply #2 on: July 18, 2010, 07:42:08 am »
These look good, Tom

mart.vader

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Re: TLP Project - Lunar Swirls
« Reply #3 on: October 18, 2010, 02:00:12 pm »
Is this a lunar swirl?


ID: AMZ30000jr
Latitude: 19.7886°
Longitude: 30.9329°
Sun Angle: -55.43°
Scale: 12.27 meters / pixel
Zoom Level: 1   (Out / In)

and

ID: AMZ30000js
Latitude: 19.6311°
Longitude: 30.9316°
Sun Angle: -55.43°
Scale: 12.27 meters / pixel
Zoom Level: 1   (Out / In)


Sorry, I don't know how to attach the photo, if you can advise, Thanks

Geoff

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Re: TLP Project - Lunar Swirls
« Reply #4 on: October 19, 2010, 09:32:12 am »
Is this a lunar swirl?

ID: AMZ30000jr
Latitude: 19.7886°
Longitude: 30.9329°
Sun Angle: -55.43°
Scale: 12.27 meters / pixel
Zoom Level: 1   (Out / In)

and

ID: AMZ30000js
Latitude: 19.6311°
Longitude: 30.9316°
Sun Angle: -55.43°
Scale: 12.27 meters / pixel
Zoom Level: 1   (Out / In)

Sorry, I don't know how to attach the photo, if you can advise, Thanks

Here's your first image:


ID: AMZ30000jr
Latitude: 19.7886°
Longitude: 30.9329°

I can't see any sign of a lunar swirl here. This is an interesting area and is just south of the Apollo 17 landing site.
The following image shows the landing site as a blue dot (your image is located about 15mm south of the blue dot):



Apollo 17 landing site - image from NASA

For help in posting images go here: Posting Images

mart.vader

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Re: TLP Project - Lunar Swirls
« Reply #5 on: October 19, 2010, 01:15:29 pm »
Thanks Geoff,

I'll keep looking.

claymore

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Re: TLP Project - Lunar Swirls
« Reply #6 on: October 29, 2010, 07:06:10 am »
How about this one?





# ID: AMZ4001ql7
# Latitude: -9.15991°
# Longitude: 15.4751°
# ID: AMZ4001qov
# Latitude: -9.14517°
# Longitude: 15.4887°

Geoff

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Re: TLP Project - Lunar Swirls
« Reply #7 on: October 29, 2010, 06:27:46 pm »
How about this one?

[images snipped]

# ID: AMZ4001ql7
# Latitude: -9.15991°
# Longitude: 15.4751°
# ID: AMZ4001qov
# Latitude: -9.14517°
# Longitude: 15.4887°

I first thought this was just light-coloured rays from the nearby crater but did some research and there may be faint “swirls” in this area.

The ray crater on the left of the image is called “South Ray” on the LROC Image Map and is close to Dollond T crater and the Apollo 16 site. It has been dated using samples returned by Apollo at about 2 million years.
See this article for more info (PDF format): Optical Maturity Study of Stuart’s Crater
and this interesting NASA article about the Apollo 16 geological results (PDF format): Summary of Geologic Results from Apollo 16

Your images are from LROC Strip: M106777343RC

This image is an overview of the east side of the South Ray crater.

East of South Ray crater - possible swirl?

This strip also contains the Apollo 16 landing site:


Apollo 16 Site
« Last Edit: November 17, 2010, 09:53:31 am by Geoff »

Tom128

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Re: TLP Project - Lunar Swirls
« Reply #8 on: October 30, 2010, 12:17:16 am »
Hi Geoff and Claymore,

There may be a possibility that what appears to be swirls are actually depressions or rises/mounds where the ejecta blew over/around the area or the albedo light  change is darker. If you review other parts of the photo strip you can see the swirl like formations without the ejecta that leads one to believe there is a topographical change on the surface.

The lunar surface is riddled with craters, mounds and other formations that make the case for lunar swirls to be quite an anomaly and ejecta patterns to be more a case of painting the contours, indentations and rises with the albedo effect.
« Last Edit: October 30, 2010, 12:51:55 am by Tom128 »

Geoff

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Re: TLP Project - Lunar Swirls
« Reply #9 on: October 30, 2010, 06:37:49 am »
Hi Geoff and Claymore,

There may be a possibility that what appears to be swirls are actually depressions or rises/mounds where the ejecta blew over/around the area or the albedo light  change is darker. If you review other parts of the photo strip you can see the swirl like formations without the ejecta that leads one to believe there is a topographical change on the surface.

The lunar surface is riddled with craters, mounds and other formations that make the case for lunar swirls to be quite an anomaly and ejecta patterns to be more a case of painting the contours, indentations and rises with the albedo effect.

Good points Tom. It's difficult finding "genuine" swirls as they need to be large enough to stand out from the background "pseudo" swirls.

I did find one article that mentioned that there was a magnetic anomaly in this area of the Moon and if this is so then there may be smaller swirls associated with it.
See: http://www.agu.org/pubs/crossref/2005/2004JE002380.shtml

Tom128

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Re: TLP Project - Lunar Swirls
« Reply #10 on: April 23, 2011, 05:21:50 am »
Here is a link using the Act-React tool of the area where Geoff's “Butterfly swirl”  example is located.  Very interesting!

http://target.lroc.asu.edu/da/qmap.html?mv=eqc&mcx=4959951.42041&mcy=-1025714.36527&mz=10&ml=FTFB00TT


« Last Edit: April 26, 2011, 05:32:56 pm by Tom128 »

IreneAnt

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Re: TLP Project - Lunar Swirls
« Reply #11 on: April 28, 2011, 11:50:31 am »
How about this one?
# ID: AMZ4001ql7
# Latitude: -9.15991°
# Longitude: 15.4751°
# ID: AMZ4001qov
# Latitude: -9.14517°
# Longitude: 15.4887°
I first thought this was just light-coloured rays from the nearby crater but did some research and there may be faint “swirls” in this area.

The ray crater on the left of the image is called “South Ray” on the LROC Image Map and is close to Dollond T crater and the Apollo 16 site. It has been dated using samples returned by Apollo at about 2 million years.
See this article for more info (PDF format): Optical Maturity Study of Stuart’s Crater
and this interesting NASA article about the Apollo 16 geological results (PDF format): Summary of Geologic Results from Apollo 16

Your images are from LROC Strip: M106777343RC

This image is an overview of the east side of the South Ray crater.

East of South Ray crater - possible swirl?
Hi Geoff and Claymore,

There may be a possibility that what appears to be swirls are actually depressions or rises/mounds where the ejecta blew over/around the area or the albedo light  change is darker. If you review other parts of the photo strip you can see the swirl like formations without the ejecta that leads one to believe there is a topographical change on the surface.

The lunar surface is riddled with craters, mounds and other formations that make the case for lunar swirls to be quite an anomaly and ejecta patterns to be more a case of painting the contours, indentations and rises with the albedo effect.


Hi Tom,

Historically, the lunar swirls have been interesting because they are NOT associated with any kind of topographic feature at all. I think what you are seeing in the image above are just the intricacies of ejecta. When multiple impacts occur at the same time, as they would in the emplacement of ejecta, the ejecta of the different impacts interfere with each other, often forming these wispy, feathery patterns.

By the way, I took a look at the references provided by Geoff and can find no mention of swirls in either of them. Geoff, I would be interested in seeing the research that indicates that there are "faint swirls" in this area.

kodemunkey

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Re: TLP Project - Lunar Swirls
« Reply #12 on: October 02, 2011, 12:07:49 pm »
Sorry if this is gravedigging, but i think i found one.


ID: AMZ30000cr
Latitude: 48.8541°
Longitude: 2.50253°
Sun Angle: -59.11°
Scale: 14.14 meters / pixel
Zoom Level: 1

Geoff

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Re: TLP Project - Lunar Swirls
« Reply #13 on: October 02, 2011, 12:35:54 pm »
I think this is more a topographical feature than a swirl.

kodemunkey

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Re: TLP Project - Lunar Swirls
« Reply #14 on: October 03, 2011, 11:12:24 am »
Swirly Swirly





ID: AMZ30000hs
Latitude: 12.1776°
Longitude: 62.5524°
Sun Angle: -67.12°
Scale: 11.80 meters / pixel
Zoom Level: 1