Nice image, John!
Are you guys sure those are plumes? I know at least one of those is a mountain, need to check the old Galileo/Voyager map again... However, this is in the area of 0405A and the south Karei giant plume deposit from July 1999, as well as the field of hotspots seen by Galileo so I guess it's possible.
Full Version: New Horizons at Io
In addition to the very nice MVIC image posted today, two additional LORRI images were posted in the New Horizons SOC page. These two images come from two sequences prior to Jupiter C/A: Ieclipse3 and Iocc1.
Click to view attachment
Only one LORRI image was taken during the first of the two new image sets, Iocc1. Attached above is the 10-msec exposure taken and a Celestia simulated view from the same time frame. The image is centered at 6.6 South, 35.1 West and has a resolution of 22.5 km/pixel. This image shows Io's leading hemisphere with a spotlight on Tarsus Regio and Media Regio. Much of the surface on the left side is overexposed, but the terrain within 45 degrees of the terminator appears to be well-exposed. A few things to point out include the larger flow field at North Kanehekili and a small ring around a patera at 7 South, 20 West (perhaps associated with the middle of the three bright spots seen in the MVIC image released today). EDIT: scratch that, the "ring" was seen by Galileo during the 11th orbit. There may be a darkening at a patera at 57 North, 40 West.
Click to view attachmentClick to view attachment
The other image posted is from the beginning of the Ieclipse3 sequence. This is the first of a possible 30 images that have not been posted yet. This image shows the trailing hemisphere of Io and is centered at 7.6 South, 300.3 West. This image has a resolution of 13.6 km/pixel. Prominent features visible in this image include Pele right on the terminator at lower right, Loki just above center, Northern Lerna Regio at lower right, Ra Patera just left of center, and Karei Patera near the limb at center left. This image provides a clearer view of Creidne Patera, the site of a large eruption in 2004 and a major surface change seen by New Horizons. This image seems to indicate that the new flows are located along the eastern and southern portions of the patera, apparently anti-correlated with previous dark flows seen there by Voyager and Galileo. A dark outflow is seen at Euboea Fluctus, though that was seen by Galileo.
I've added both images to the movie above.
Click to view attachment
Only one LORRI image was taken during the first of the two new image sets, Iocc1. Attached above is the 10-msec exposure taken and a Celestia simulated view from the same time frame. The image is centered at 6.6 South, 35.1 West and has a resolution of 22.5 km/pixel. This image shows Io's leading hemisphere with a spotlight on Tarsus Regio and Media Regio. Much of the surface on the left side is overexposed, but the terrain within 45 degrees of the terminator appears to be well-exposed. A few things to point out include the larger flow field at North Kanehekili and a small ring around a patera at 7 South, 20 West (perhaps associated with the middle of the three bright spots seen in the MVIC image released today). EDIT: scratch that, the "ring" was seen by Galileo during the 11th orbit. There may be a darkening at a patera at 57 North, 40 West.
Click to view attachmentClick to view attachment
The other image posted is from the beginning of the Ieclipse3 sequence. This is the first of a possible 30 images that have not been posted yet. This image shows the trailing hemisphere of Io and is centered at 7.6 South, 300.3 West. This image has a resolution of 13.6 km/pixel. Prominent features visible in this image include Pele right on the terminator at lower right, Loki just above center, Northern Lerna Regio at lower right, Ra Patera just left of center, and Karei Patera near the limb at center left. This image provides a clearer view of Creidne Patera, the site of a large eruption in 2004 and a major surface change seen by New Horizons. This image seems to indicate that the new flows are located along the eastern and southern portions of the patera, apparently anti-correlated with previous dark flows seen there by Voyager and Galileo. A dark outflow is seen at Euboea Fluctus, though that was seen by Galileo.
I've added both images to the movie above.
QUOTE (john_s @ April 16th, 2007, 04:18 PM) 
Hi Folks-
We've been slow about posting new images on the New Horizons web site lately (we're concentrating on a batch of releases for the post-Jupiter press conference on May 1st), but here's a new one, an MVIC color image showing the night side of Io illuminated by Jupiter:
http://www.pluto.jhuapl.edu/gallery/missio...ges/041607.html
Click to view attachment
John.
We've been slow about posting new images on the New Horizons web site lately (we're concentrating on a batch of releases for the post-Jupiter press conference on May 1st), but here's a new one, an MVIC color image showing the night side of Io illuminated by Jupiter:
http://www.pluto.jhuapl.edu/gallery/missio...ges/041607.html
Click to view attachment
John.
Fantastic image you have there.
Click to view attachment
Another new Io sequence is now up on the LORRI raw images page. This sequence, Ihiresir3, was taken on February 28, 2007 at 4:40UTC. The MVIC image from this sequence was released last week. Combining the two might be possible, but it would largely have to wait until the PDS release due to the loss of information on the Jupiter-shine region from the conversion to JPEG. These images are centered near 6.0 South Latitude, 25.8 West Longitude and have a resolution of 13.25 km/pixel. The four images shown here are (clockwise from upper left): the 4-msec exposure, the 20-msec exposure, a Celestia preview image, and a 75-msec exposure.
This observation is very similar to the Ihires4 observation I've discussed earlier. You can see the Tvashtar and Amirani plumes on the limb. A number of mountains are visible near the limb. The Masubi plume deposit is clearly visible at lower left in each view.
Another new Io sequence is now up on the LORRI raw images page. This sequence, Ihiresir3, was taken on February 28, 2007 at 4:40UTC. The MVIC image from this sequence was released last week. Combining the two might be possible, but it would largely have to wait until the PDS release due to the loss of information on the Jupiter-shine region from the conversion to JPEG. These images are centered near 6.0 South Latitude, 25.8 West Longitude and have a resolution of 13.25 km/pixel. The four images shown here are (clockwise from upper left): the 4-msec exposure, the 20-msec exposure, a Celestia preview image, and a 75-msec exposure.
This observation is very similar to the Ihires4 observation I've discussed earlier. You can see the Tvashtar and Amirani plumes on the limb. A number of mountains are visible near the limb. The Masubi plume deposit is clearly visible at lower left in each view.
Tomorrow is the big, post-Jupiter encounter press conference (at 2pm EDT, 11am Volcanopele Standard Time). Hopefully we will see some results from LEISA or LORRI eclipse observations, which would show which volcanoes on Io are currently active. Right now, we have only seen on hotspot (at Tvashtar), and plumes at Prometheus, Amirani, and Masubi (and maybe Zal), indicating continued activity. For example, it would be interesting to see if Shango Patera is still an active eruption site. The surface change at Shango Patera reminds me of Thor and Pillan. Based on our experience at Pillan, a hotspot should still be evident for at least a year after the eruption. So, who knows... The other major surface changes (besides Tvashtar, of course) can be tied to prior eruptions that occurred over the last 5 years, though the Northern Lerna Regio eruption is a little iffy since the only indication of an eruption there comes from a comment in a presentation stating that an eruption "close to Svarog" occurred in July 2005.
BTW, anyone know if press conferences like this are saved somewhere afterward or a way I can save the stream on my computer? Since this is a bit (just a bit...) off-topic, please pm or email me if you can help me.
BTW, anyone know if press conferences like this are saved somewhere afterward or a way I can save the stream on my computer? Since this is a bit (just a bit...) off-topic, please pm or email me if you can help me.
Best place I've found for NASA TV and copies of old televised events is
http://www.space-multimedia.nl.eu.org/index.php
The quality is generally better than the Nasa-TV feed (!). The updates list at
http://www.space-multimedia.nl.eu.org/inde...=1&Itemid=2
is pretty MSF oriented, but it includes stuff like the STEREO press conferences etc.
http://www.space-multimedia.nl.eu.org/index.php
The quality is generally better than the Nasa-TV feed (!). The updates list at
http://www.space-multimedia.nl.eu.org/inde...=1&Itemid=2
is pretty MSF oriented, but it includes stuff like the STEREO press conferences etc.
A lot of cool stuff all around. Glad to see the eclipse images. Gotta love a mystery volcano.
Based on just eyeballing these hotspot images, I could find the following hotspots (better stuff coming later):
From http://pluto.jhuapl.edu/gallery/missionPho.../050107_08.html:
Pele
Reiden
E. Girru (the mystery volcano John mentioned in the press conference)
N. Lerna
Ra Patera
Amaterasu Patera
Cast of dozens (sub-Jovian crew)
From http://pluto.jhuapl.edu/gallery/missionPho.../050107_04.html:
Tvashtar
Amirani
Prometheus
Culann
Tupan
Malik
Shamash
Unnamed volcano at 42.5 South, 174.5 West (Southwestern Mycenae Regio)
Hotspot north of Prometheus (Chaac or Sobo)
Zamama
Maybe another hotspot just south of Tvashtar (Thor or Savitr), could be scattered light though
From http://pluto.jhuapl.edu/news_center/news/p.../Spencer_06.jpg:
Pele
Reiden
E. Girru
Isum
Donar
Mulungu
Pillan
Zamama
Marduk
Unnamed volcano at 10 South, 217.5 West
Culann
Prometheus
In the third image, you can see Io's anti-Jovian hemisphere in Europa-shine, particularly revealing the albedo features near Isum Patera, Donar Fluctus, and Colchis Regio. Like a similar Galileo image, bright material in the northern reaches of Lei-Kung Fluctus is glowing...ummm, why???? SO2 sublimation perhaps... or deposition?
From http://pluto.jhuapl.edu/gallery/missionPho.../050107_08.html:
Pele
Reiden
E. Girru (the mystery volcano John mentioned in the press conference)
N. Lerna
Ra Patera
Amaterasu Patera
Cast of dozens (sub-Jovian crew)
From http://pluto.jhuapl.edu/gallery/missionPho.../050107_04.html:
Tvashtar
Amirani
Prometheus
Culann
Tupan
Malik
Shamash
Unnamed volcano at 42.5 South, 174.5 West (Southwestern Mycenae Regio)
Hotspot north of Prometheus (Chaac or Sobo)
Zamama
Maybe another hotspot just south of Tvashtar (Thor or Savitr), could be scattered light though
From http://pluto.jhuapl.edu/news_center/news/p.../Spencer_06.jpg:
Pele
Reiden
E. Girru
Isum
Donar
Mulungu
Pillan
Zamama
Marduk
Unnamed volcano at 10 South, 217.5 West
Culann
Prometheus
In the third image, you can see Io's anti-Jovian hemisphere in Europa-shine, particularly revealing the albedo features near Isum Patera, Donar Fluctus, and Colchis Regio. Like a similar Galileo image, bright material in the northern reaches of Lei-Kung Fluctus is glowing...ummm, why???? SO2 sublimation perhaps... or deposition?
The Tvashtar plume being visible in this IR view caught me by surprise.
Seems like it would enable this analysis: We can see what temperature the plume "snow" is as a function of where in the plume it is. That should tell us the particle size (or thermal inertia, anyway) because it tells us the rate at which the particles cool in the vacuum of near-Io space. Yes?
Seems like it would enable this analysis: We can see what temperature the plume "snow" is as a function of where in the plume it is. That should tell us the particle size (or thermal inertia, anyway) because it tells us the rate at which the particles cool in the vacuum of near-Io space. Yes?
Actually the plume isn't visible in the infrared (though we looked hard for it!), just the hot spot on the surface. Too bad!
John.
John.
Here is the LEISA observation superimposed on a Galileo basemap. Looks like Sobo Fluctus and Thor where at little active.
Click to view attachment
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I think the small volcano marked with the arrows in the images below is the source of the E. Girru or Mystery Volcano eruption mentioned by Johh_s in the press conference:
Click to view attachment
Click to view attachment
Here is an updated list based on the figures above (around 57 hotspots):
From http://pluto.jhuapl.edu/gallery/missionPho.../050107_08.html:
Pele, Reiden, E. Girru, N. Lerna Regio, Ra Patera, Amaterasu Patera, Mazda Paterae, Tol-Ava Patera, E. Horus, southwestern portion of Loki Patera?, Hephaestus Patera, Purgine Patera, Sed Patera, Galai Patera, Manua Patera, Fuchi Patera, an unnamed patera at 24.5 North, 335.5 West, Tiermes Patera, Nyambe Patera, an unnamed patera at 5 North, 344 West, an unnamed patera at 3 South, 350 West, Ruwa Patera, an unnamed volcano at 3 South, 355 West, Fjorgynn Fluctus?, NW Fjorgynn, an unnamed volcano at 4 North, 357.5 West, Mama Patera, Ilmarinen Patera, an unnamed volcano at 10 South, 10 West, Karei Patera, and an unnamed volcano at 7 South, 20.5 West
From http://pluto.jhuapl.edu/gallery/missionPho.../050107_04.html:
Tvashtar, Amirani, Prometheus, Culann, Tupan, Malik, Shamash, an unnamed patera at 42.5 South, 174.5 West (Southwestern Mycenae Regio) and the flows to the northwest of that patera, Sobo Fluctus, Zamama, Thor
From http://pluto.jhuapl.edu/news_center/news/p.../Spencer_06.jpg:
Pele, Reiden Patera, E. Girru, Isum Patera, unnamed volcano at 28 North, 192 West, Mulungu Patera, Llew Patera, Pillan Patera, Zamama, Marduk, an unnamed patera at 10 South, 217.5 West, Culann Patera, Prometheus, Hephaestus Patera, Purgine Patera, an unnamed patera at 4 North, 283.5 West, an unnamed patera at 1.5 North, 193.5 West, an unnamed patera at 6.5 North, 188 West, an unnamed patera and flow field at 3 North, 184 West, Kurdalagon Patera, Sethlaus Patera, an unnamed patera at 42.5 South, 174.5 West (Southwestern Mycenae Regio), N. Lerna Regio, Loki (maybe), S. Caucasus, and an unnamed patera at 4 North, 209 West
From http://pluto.jhuapl.edu/gallery/missionPho.../050107_08.html:
Pele, Reiden, E. Girru, N. Lerna Regio, Ra Patera, Amaterasu Patera, Mazda Paterae, Tol-Ava Patera, E. Horus, southwestern portion of Loki Patera?, Hephaestus Patera, Purgine Patera, Sed Patera, Galai Patera, Manua Patera, Fuchi Patera, an unnamed patera at 24.5 North, 335.5 West, Tiermes Patera, Nyambe Patera, an unnamed patera at 5 North, 344 West, an unnamed patera at 3 South, 350 West, Ruwa Patera, an unnamed volcano at 3 South, 355 West, Fjorgynn Fluctus?, NW Fjorgynn, an unnamed volcano at 4 North, 357.5 West, Mama Patera, Ilmarinen Patera, an unnamed volcano at 10 South, 10 West, Karei Patera, and an unnamed volcano at 7 South, 20.5 West
From http://pluto.jhuapl.edu/gallery/missionPho.../050107_04.html:
Tvashtar, Amirani, Prometheus, Culann, Tupan, Malik, Shamash, an unnamed patera at 42.5 South, 174.5 West (Southwestern Mycenae Regio) and the flows to the northwest of that patera, Sobo Fluctus, Zamama, Thor
From http://pluto.jhuapl.edu/news_center/news/p.../Spencer_06.jpg:
Pele, Reiden Patera, E. Girru, Isum Patera, unnamed volcano at 28 North, 192 West, Mulungu Patera, Llew Patera, Pillan Patera, Zamama, Marduk, an unnamed patera at 10 South, 217.5 West, Culann Patera, Prometheus, Hephaestus Patera, Purgine Patera, an unnamed patera at 4 North, 283.5 West, an unnamed patera at 1.5 North, 193.5 West, an unnamed patera at 6.5 North, 188 West, an unnamed patera and flow field at 3 North, 184 West, Kurdalagon Patera, Sethlaus Patera, an unnamed patera at 42.5 South, 174.5 West (Southwestern Mycenae Regio), N. Lerna Regio, Loki (maybe), S. Caucasus, and an unnamed patera at 4 North, 209 West
http://pluto.jhuapl.edu/news_center/news/p.../Spencer_03.jpg
One of the slides john_s showed today displays three additional plumes in addition to the 4 observed thus far at Io during this encounter (Tvashtar, Amirani, Masubi, and Tvashtar). As mentioned in the press conference, the plume on the limb is associated with the Northern Lerna Regio eruption. Just beyond the terminator are two additional plumes. The northern plume is associated with the persistent hotspot, Marduk. A plume was also observed at Marduk by Voyager and Galileo. The southern plume is associated with Kurdalagon Patera, a persistent hotspot. AFAIK, no plume has ever been seen at this volcano.
BTW, Kurdalagon, weirdest plume deposit since Euboea:
Click to view attachment
One of the slides john_s showed today displays three additional plumes in addition to the 4 observed thus far at Io during this encounter (Tvashtar, Amirani, Masubi, and Tvashtar). As mentioned in the press conference, the plume on the limb is associated with the Northern Lerna Regio eruption. Just beyond the terminator are two additional plumes. The northern plume is associated with the persistent hotspot, Marduk. A plume was also observed at Marduk by Voyager and Galileo. The southern plume is associated with Kurdalagon Patera, a persistent hotspot. AFAIK, no plume has ever been seen at this volcano.
BTW, Kurdalagon, weirdest plume deposit since Euboea:
Click to view attachment
Coolness, Jason! Do you know how many more frames you expect to see?
--Emily
--Emily
Looks like around 13 more frames for a total of 35 frames. I am of course, skipping eclipse frames.
There are a number of new Io images on the LORRI raw images page. I'm not going to cover these like I've done before (unless you guys really want me to), but needless to say there is a lot of coolness there. Like several images of the Tvashtar and its glowing lava (in daylight no less), the three southern hemisphere plumes, and numerous eclipse images.
One of the interesting topics covered in yesterday's press conference is the field of bright spots seen near the pro- and anti-Jovian points on Io when it is in eclipse. Now, correct me John if I get any of this wrong, but basically it is thought that these represent areas near volcanic vents where gas is being excited by the electrical current running between Jupiter and Io, which connect to Io through the pro- and anti-Jovian points on the surface.
I'm thinking that each and every one of those spots represent an active volcano. However, the bright spots seen are what are described in the press conference, glowing gas. The greater heat flow at these volcanoes is enough to increase the column density of the atmosphere above each of these volcanoes, making them appear brighter in this region. The volcanoes or the density of volcanoes may not be all that unusual, but their location near the pro- and anti-Jovian points puts them in a position where the gases above the volcanoes are excited. The Galileo NIMS instrument showed that the number of active vents observed increases as you improve spatial resolution. For example, in the Chaac-Camaxtli region, 6 hotspots where observed in high resolution observation taken in February 2001. Lower-resolution data showed only a couple. So the density of volcanic vents observed in eclipse at the pro- and anti-jovian points may be typical of the density across the rest of the surface, but the effect of the electric current on the gases near these vents improves their visibility even in these eclipse observations.
Bottom line, many of the glowing spots near the pro- and anti-jovian points, observed when Io is in eclipse, represent active volcanic vents, but the glow itself comes from glowing gases, not thermal emission.
I'm thinking that each and every one of those spots represent an active volcano. However, the bright spots seen are what are described in the press conference, glowing gas. The greater heat flow at these volcanoes is enough to increase the column density of the atmosphere above each of these volcanoes, making them appear brighter in this region. The volcanoes or the density of volcanoes may not be all that unusual, but their location near the pro- and anti-Jovian points puts them in a position where the gases above the volcanoes are excited. The Galileo NIMS instrument showed that the number of active vents observed increases as you improve spatial resolution. For example, in the Chaac-Camaxtli region, 6 hotspots where observed in high resolution observation taken in February 2001. Lower-resolution data showed only a couple. So the density of volcanic vents observed in eclipse at the pro- and anti-jovian points may be typical of the density across the rest of the surface, but the effect of the electric current on the gases near these vents improves their visibility even in these eclipse observations.
Bottom line, many of the glowing spots near the pro- and anti-jovian points, observed when Io is in eclipse, represent active volcanic vents, but the glow itself comes from glowing gases, not thermal emission.
Volcanopele,
You're right about that aurora, it's gas (SO2) excited by electrons. However, those two spots at opposite sides of the equator need not be anywhere near a volcano. The SO2 gas from the volcanos has spread around the planet to form a tenous atmosphere.
Side note: this SO2 atmosphere freezes onto the poles, that's why the poles are bright (in the visible spectrum).
There's a great movie of Io's aurora from Cassini's flyby of Jupiter. It's in a Science paper by Porco and others under "Supplemental online material." If you can't access it, I'd be happy to email it. tac2z@virginia.edu
You're right about that aurora, it's gas (SO2) excited by electrons. However, those two spots at opposite sides of the equator need not be anywhere near a volcano. The SO2 gas from the volcanos has spread around the planet to form a tenous atmosphere.
Side note: this SO2 atmosphere freezes onto the poles, that's why the poles are bright (in the visible spectrum).
There's a great movie of Io's aurora from Cassini's flyby of Jupiter. It's in a Science paper by Porco and others under "Supplemental online material." If you can't access it, I'd be happy to email it. tac2z@virginia.edu
QUOTE (tim cassidy @ May 3 2007, 08:47 AM)
You're right about that aurora, it's gas (SO2) excited by electrons. However, those two spots at opposite sides of the equator need not be anywhere near a volcano. The SO2 gas from the volcanos has spread around the planet to form a tenous atmosphere.
That explains the two very bright spots seen on the limb near the sub- and anti-Jovian points (actually they rock north and south of the equator depending on Io's position WRT the Jovian magnetosphere). I was referring to the smaller bright spots dotted across the disk of Io near that point.
QUOTE
Side note: this SO2 atmosphere freezes onto the poles, that's why the poles are bright (in the visible spectrum).
Is that why the bright albedo regions in the north polar region are visible in eclipse? Because the atmosphere is freezing out there?
QUOTE
Is that why the bright albedo regions in the north polar region are visible in eclipse? Because the atmosphere is freezing out there?
I had that backward, the poles are darker (because the SO2 doesn't make it up there?) in the visible. I didn't notice any surface features in the eclipse images.
Below are two eclipse image compared to a reprojected version of the new USGS basemap. The first eclipse image is from Galileo during orbit E11. The image was taken on Nov. 8, 1997 at 11:44 UTC and has a resolution of 13.6 km/pixel. This image shows hotspots on Io's trailing hemisphere, glows along the limb, and glows in the north polar region, and surface features illuminated by Europa-shine. The second eclipse images is from New Horizons, the Ieclipse4 observation. The image is a merge, from the press conference, of at least two eclipse images and was taken on March 1, 2007. The original images had a resolution of 53.084 km/pixel but were magnified 4x here. Once again, the image shows hotspots on Io's trailing hemisphere, glows along the limb, and glows in the north polar region, and several surface features illuminated by Europa-shine.
Many of the N. Polar glows remain consistent. Of particular note is a glow over a very bright spot (the bright spot on Io in terms of Bond albedo, from Simonelli et al. 2001) at 67.5 North, 195 West.
Click to view attachmentClick to view attachmentClick to view attachment
Many of the N. Polar glows remain consistent. Of particular note is a glow over a very bright spot (the bright spot on Io in terms of Bond albedo, from Simonelli et al. 2001) at 67.5 North, 195 West.
Click to view attachmentClick to view attachmentClick to view attachment
Looking at that image again, perhaps one should be on the look out for a plume at Hephaestus Patera...
Rather than upload a new movie here ever time a new LORRI image shows up, I'm just going to put it at:
http://pirlwww.lpl.arizona.edu/~perry/Io_movie.gif
http://pirlwww.lpl.arizona.edu/~perry/Io_movie.gif
Terrific, VP; thanks! 
Now we have an "proper" movie of the Tvashtar plume- here's the animated GIF:
Click to view attachment
See http://www.pluto.jhuapl.edu/gallery/missio...ges/051407.html for more details...
John.
Click to view attachment
See http://www.pluto.jhuapl.edu/gallery/missio...ges/051407.html for more details...
John.
Bravo!!!!!
!! that's my second 'wow' in less than 5 minutes. i love this place.
WOW!
WOW!
VERY SWEET!!
Just flipping through the SOC images too, there are definitely two plumes at Masubi. Nice to know I wasn't crazy...
Just flipping through the SOC images too, there are definitely two plumes at Masubi. Nice to know I wasn't crazy...
Here is a graphic illustrating the changes at Masubi, and the sources of the two plumes:
Click to view attachment
The images on the left are from New Horizons and show the new lava flow emanating from the Masubi source region. The source region is the origin of the northern of the two plumes. The southern of the two plumes comes from the flow front of the new lobe of Masubi Fluctus. The image on the right is from Galileo (orbit C9, June 1997). The last Galileo image of the region, taken in August 1999, shows a plume deposit surrounding the source region.
Click to view attachment
The images on the left are from New Horizons and show the new lava flow emanating from the Masubi source region. The source region is the origin of the northern of the two plumes. The southern of the two plumes comes from the flow front of the new lobe of Masubi Fluctus. The image on the right is from Galileo (orbit C9, June 1997). The last Galileo image of the region, taken in August 1999, shows a plume deposit surrounding the source region.
Wow here too.
QUOTE (volcanopele @ Mar 13 2007, 11:33 PM)
Well, after a little work, I found the vent:
This of course assumes that the bright spot is a hotspot (similar to those seen by SSI on Galileo, though LORRI doesn't have the same wavelength response, only sensing up to 850 nm IIRC).
So what do we know about this area? Well, the source appears to be in the far left patera of Tvashtar Paterae. See http://photojournal.jpl.nasa.gov/catalog/PIA03529 for a good image of this region. In particular, the glowing spot appears to be localized within the dolphin-shaped flow along the southern and eastern margin of this patera. A temperature map from the 2000/2001 eruption at this flow can be seen at http://photojournal.jpl.nasa.gov/catalog/PIA02594. Strangely enough, despite the energetic eruption that year, the morphology of the flow didn't change from before the eruption (see http://photojournal.jpl.nasa.gov/catalog/PIA02584 if you don't believe me). It definitely would seem that eruptions at this lava flow produce quite a bit of pyroclastic material, producing a dark deposit in the immediate vicinity of the flow and a giant plume producing a red ring distally.
This of course assumes that the bright spot is a hotspot (similar to those seen by SSI on Galileo, though LORRI doesn't have the same wavelength response, only sensing up to 850 nm IIRC).
So what do we know about this area? Well, the source appears to be in the far left patera of Tvashtar Paterae. See http://photojournal.jpl.nasa.gov/catalog/PIA03529 for a good image of this region. In particular, the glowing spot appears to be localized within the dolphin-shaped flow along the southern and eastern margin of this patera. A temperature map from the 2000/2001 eruption at this flow can be seen at http://photojournal.jpl.nasa.gov/catalog/PIA02594. Strangely enough, despite the energetic eruption that year, the morphology of the flow didn't change from before the eruption (see http://photojournal.jpl.nasa.gov/catalog/PIA02584 if you don't believe me). It definitely would seem that eruptions at this lava flow produce quite a bit of pyroclastic material, producing a dark deposit in the immediate vicinity of the flow and a giant plume producing a red ring distally.
Okay, I gave this another go. After very carefully matching up an Io basemap to the Ihires6 sequence of images (like this one: http://pluto.jhuapl.edu/gallery/missionPho.../050107_02.html ), it looks like the vent is actually a little further to the east than I proposed earlier. I now think that it is at the Galileo I25 lava curtain location (see http://pirlwww.lpl.arizona.edu/~perry/io_i...5ISGIANTS01.png )
I'll post a more complete work-up when later tonight.
As promised:
Click to view attachment
The image on the left is from lor_0034981639_0x630_sci_1 . This image shows a hotspot at Tvashtar, likely the source of the large plume. The image on the right is the USGS basemap reprojected to the same geometry as the LORRI image. By blinking the two images, I was able to pinpoint the hotspot to the location marked by the blue point near the top of the right hand image. This suggests that the hotspot is at the same location as a 25-km long fire fountain seen by Galileo in November 1999. This identification is supported by the history of this location in producing a hotspot visible in clear filter images, at low exposure times, in broad daylight. The error window for this hotspot is about twice the size of the spot, since I don't know the exact resolution and central lat and lon leading to slight diferences between the two images.
Click to view attachment
The image on the left is from lor_0034981639_0x630_sci_1 . This image shows a hotspot at Tvashtar, likely the source of the large plume. The image on the right is the USGS basemap reprojected to the same geometry as the LORRI image. By blinking the two images, I was able to pinpoint the hotspot to the location marked by the blue point near the top of the right hand image. This suggests that the hotspot is at the same location as a 25-km long fire fountain seen by Galileo in November 1999. This identification is supported by the history of this location in producing a hotspot visible in clear filter images, at low exposure times, in broad daylight. The error window for this hotspot is about twice the size of the spot, since I don't know the exact resolution and central lat and lon leading to slight diferences between the two images.
Late to the party re the plume movie..."wow" don't cut it, gotta bust loose with a <CLINK!!!> What a sight... 
*clink* in the swear box. 1st in some weeks. Still spectacular after reading the notes and figuring a ~10**3X speedup.
Lovely animation! And if the plume's about 250km high, then the gunk is rocketing out of Io at around ... ummm ... 900 m/s.
<clink><clink><clink>
Andy
<clink><clink><clink>
Andy
Have just seen the plume movie on Emily's blog @ TPS.
WOW!
WOW!
...
Just think what we might have seen IF Galileo's main antenna hadn't got stuck. Some more tears shed here.
Just think what we might have seen IF Galileo's main antenna hadn't got stuck. Some more tears shed here.
Neat image of Io being occulted by Jupiter. Edge of Tvashtar's plume visible at the top.
I hadn't realized that was a Jupiter occultation -- just thought it was subframed for some reason. Now I can see the disk, and realize from the exposure time of 100 ms that the surface of Io is lit by Jupitershine. That is a cool picture!--Emily
QUOTE (Tesheiner @ May 16 2007, 11:55 AM)
Have just seen the plume movie on Emily's blog @ TPS.
WOW!
WOW!
Indeed awesome.
What a movie! Together with the dust devil movies on Mars they remind me that the Earth is not the only active place in the solar system.
Enthusiasm + good planning + a bit of luck = awesome movie
Enthusiasm + good planning + a bit of luck = awesome movie
QUOTE (elakdawalla @ May 16 2007, 03:46 PM)
I hadn't realized that was a Jupiter occultation -- just thought it was subframed for some reason. Now I can see the disk, and realize from the exposure time of 100 ms that the surface of Io is lit by Jupitershine. That is a cool picture!--Emily
Note the plume mirage too- the short streak extending from the edge of Io's disk along the limb is an image of the Tvashtar plume, distorted by refraction in Jupiter's atmosphere.
John.
Wow - I've just gone back and read the first reply I made to the Kodak Moment 'RFP' from last year - and it was something similar - glad to see I wasn't entirely wrong about the atmospheric effects
Doug
Doug
As we more and more crescent views come down, be on the look out for faint plumes:
Here is a list of plumes from NH thus far:
Happy hunting
Here is a list of plumes from NH thus far:
CODE
Name Lat Lon
Masubi (north) -45 53
Masubi (south) -49 58
Zal Patera 41 75
Amirani 23 116
Tvashtar Paterae 63 123
Prometheus 1 153
Culann Patera -20 162
Illyrikon Regio -70 170
Marduk -28 210
Kurdalagon Patera -50 218
Hephaestus Patera 2 290
N. Lerna Regio -58 293
Masubi (north) -45 53
Masubi (south) -49 58
Zal Patera 41 75
Amirani 23 116
Tvashtar Paterae 63 123
Prometheus 1 153
Culann Patera -20 162
Illyrikon Regio -70 170
Marduk -28 210
Kurdalagon Patera -50 218
Hephaestus Patera 2 290
N. Lerna Regio -58 293
Happy hunting
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