SOHO Comets/Asteroids/Planets

[MeteorWayne]

Wow! The comet made it all the way into the LASCO C2 Field of View...but I think it vaporized in the last frame or two.

http://soho.esac.esa.int/data/LATEST/current_c2.gif

 

[MeteorWayne]

Check out the LASCO C3 Loop. In addition to the comet evaporating as it heads toward the sun, and Venus approaching superior conjunction (moving from right to left), you can see Mercury rapidly moving from the left edge to just above the sun in the last day or so. It is fading because it is backlit, becoming a very thin crescent (currently 0.5% illuminated)

http://soho.esac.esa.int/data/LATEST/current_c3.gif

 

[michaelmozina]

Check out the LASCO C3 Loop. In addition to the comet evaporating as it heads toward the sun, and Venus approaching superior conjunction (moving from right to left), you can see Mercury rapidly moving from the left edge to just above the sun in the last day or so. It is fading because it is backlit, becoming a very thin crescent (currently 0.5% illuminated)

http://soho.esac.esa.int/data/LATEST/current_c3.gif

http://sohodata.nascom.nasa.gov/cgi-bin ... ie_theater

I'm not sure if you noticed, but that was actually the third comet that SOHO picked up since the 26th of December following nearly the identical inbound trajectory. If you run the LASCO C-3 images from about the 25th forward, you'll probably notice something show up along the same trajectory about 23:00 of the 26th. Maybe your eyes are better than mine and you'll see it sooner, but it's more visible on the 27th. The second inbound event along the same path comes in around the 30th and then the largest one was clearly visible along roughly the same path a few days later. Those three inbound events sure seem to follow the same trajectory Wayne. I think you'll be very interested in them if you haven't already picked them all up.

That observational evidence does seem to confirm your earlier thread on meteorites following an a common orbit. I think that's really cool! Long live SOHO! By the way, do you know why the MPG 195A movies aren't updating like the Lasco MPG files? I feel a little blind relying on STEREO movies.

 

[MeteorWayne]

Rarely does a planet pass close enough to the sun to show on the LASCO C2 loop, but this time, as Venus approaches superior conjunction, it's just below the sun:

http://soho.esac.esa.int/data/LATEST/current_c2.gif

And Mercury is brightening again after inferior conjunction just to the right of the dark bar that supports the occulting disk:

http://soho.esac.esa.int/data/LATEST/current_c3.gif

 

[MeteorWayne]

http://sohodata.nascom.nasa.gov/cgi-bin ... ie_theater

I'm not sure if you noticed, but that was actually the third comet that SOHO picked up since the 26th of December following nearly the identical inbound trajectory. If you run the LASCO C-3 images from about the 25th forward, you'll probably notice something show up along the same trajectory about 23:00 of the 26th. Maybe your eyes are better than mine and you'll see it sooner, but it's more visible on the 27th. The second inbound event along the same path comes in around the 30th and then the largest one was clearly visible along roughly the same path a few days later. Those three inbound events sure seem to follow the same trajectory Wayne. I think you'll be very interested in them if you haven't already picked them all up.

That observational evidence does seem to confirm your earlier thread on meteorites following an a common orbit. I think that's really cool! Long live SOHO!

Indeed you are correct! They were both very faint and didn't last long...I had to watch the 12/26-12/28 loop several times to catch them.

Good eyes mm!!

MW

 

[MeteorWayne]

There's another small fragment on the Kreutz family orbit path on the 8th.

 

[michaelmozina]

There's another small fragment on the Kreutz family orbit path on the 8th.

Good eyes by your too. I was going to mention that last fragment but you obviously beat me to it.

 

[MeteorWayne]

You've got me lookin' real close now! :shock: :shock:

 

[MeteorWayne]

I posted this a long time ago, thought it was worth dredging up again...


The Kreutz group of sun-grazing comets have been seen for more than a millenia. The original object was disrupted thousands of years ago. Since the perihelion is so close to the sun (between 0.05 and 0.095 AU) the remaining pieces have repeatedly fallen apart leaving 500 or more tiny remnants in a highly inclined orbit that almost touches the sun. They don't approach the earth, so are not a threat to us, and the sun doesn't really care, since it vaporizes all but the very largest before they complete their perihelion pass, like these 3. Some have included the Great September Comet of 1882, Ikeya-Seki in 1965, and The Great March Comet of 1843. About 80% of SOHO comets are derived from this one massive comet of the distant past, that was likely at leat 120 km in diameter, larger than any other comet I know of.

Sungrazing Comets 101

There are two basic classes, Sungrazing comets, and Sunskirting comets, difference in perihelion defining them

Sungrazing Comets

About 90% belong to the Kreutz sungrazing group
These have 600-1100 year orbits with q (perihelion)= 0.0047-0.0095 AU
(703,000-1.4 million km, 437,000-883,000 miles). The inclination is 144.0 degrees (retrograde).

Most are small, about 16-130 meters (50-425 feet) in diameter, and only the largest,
with q /> .005 AU survive the trip.
(notice the larger one visible in the recent images did not make it, and the much smaller one a few hours earlier, didn't even make it to perihelion, evaporating on the way in.)

They are thought to have originated from one large (D=~120km) comet with a period of ~1000 years.
Between 10 and 20,000 years ago, this comet was disrupted by violent outgassing and/or tidal disruption.
The largest piece lasted until about 371 BC, when it split into 3.

The largest remaining fragment, with a period of ~350 years survived intact and was observed during returns in the 1st, 4th, 8th, and 11th centuries, and the remains may have been the Comet of 1847.
This fragment was disrupted (by the same mechanisms again) during the 11th century appearence, and gave rise to Kreutz Subgroup I
Well known comets derived from this are:
C/1443 D1 (The Great March Comet)
C/1963 R1 (Peroyra)
It also includes all the comets discovered by the SMM (10) and SOLWIND (6) satellites, and about 67% of those discovered by SOHO.

The next largest fragment from the 11th century breakup, with a period of ~700 years gave rise to Kreutz Subgroup II

 

[michaelmozina]

You've got me lookin' real close now! :shock: :shock:

They've piqued my interest too recently. FYI that last one was actually a "two-fer". Another object followed in along the same track less than 24 hours later. That's something like five inbound objects along that same track in 12-15 days.

 

[MeteorWayne]

Yes, 5 in less than a week. It's also interesting...two small dim ones, the brightest (most likely the "parent" of the other 4) then another pair of dim ones about a day apart. Really quite fascinating, considering this process started 10 or 20 thousands years ago! BTW, I checked back in tis thread, and the last group of comets occurred in February of last year, That also might be significant, possibly indicating both groups came from the next bigger fish on the organizational chart.

 

[MeteorWayne]

There's another inound Kreutz comet. For some reason, the SOHO animation doesn't show it yetm but spaceweather.com has a movie:

http://spaceweather.com/images2010/21ja ... 4tf9icl0l2

 

[MeteorWayne]

Nice two planet show from SOHO:

http://soho.esac.esa.int/data/LATEST/current_c3.gif

Jupiter is moving left to right with the stars, and Mercury pops in from the right edge moving right to left.

 

[3488]

Thanks Wayne, great stuff.

I'll see if I can pull some static JPGs from it & I'll post them here on this thread.

Andrew Brown.

 

[3488]

Here we are, Jupiter (top) & Mercury (bottom) in conjunction as seen from SOHO.

Andrew Brown.

 

[MeteorWayne]

Thanx Andrew. I can never get the images from the SOHO site to post here...have no idea why.

The star above and to the left of Jupiter is Mag +3.75 lambda Aquarii. If you look closely you can see Jupiter is not moving left to right quite as fast as the star field.

Mercury is Mag -1.2, Jupiter Mag -2.0.

 

[MeteorWayne]

http://soho.esac.esa.int/data/LATEST/current_c3.gif

2 or 3 Kreutz comets coming from the 7 o'clock position just above the bar that holds the occulting disk.

In addition, Uranus is in this image, but I don't have a way to highlight which one it is. The bright object remaining below and to the right of the sun is Mercury.

 

[3488]

Hi Wayne,

Tomorrow I will attempt to locate Uranus for you in that sequence. I will also post up some stills too.

Andrew Brown..

 

[MeteorWayne]

Here's an animation from spaceweather.com:

Here's the SOHO C3 animation:

http://spaceweather.com/images2010/12ma ... h6u9l8nhq1

Should show up in the C2 shortly, if it hasn't already:

http://soho.esac.esa.int/data/LATEST/current_c2.gif

Yes, in fact it has:

Edit: have removed current image link since it is no longer visible in the current image.

The last image with the whole comet visible so far was at 1806 UTC, the last with the tail visible was at 2206, both on March 12.

There appear to be some missing frames, hopefully they will show up. SOmetimes they do later on.

To view the C2 comet approach, go to:

http://sohodata.nascom.nasa.gov/cgi-bin ... ie_theater

Select LASCO C2, and pick, say 25 images (Select n images) for today. By tomorrow you might have to select more images, but that's good enough for now.

BTW, a nice mass ejection off the sun in the background at the 10 o'clock position.

Wayne

 

[MeteorWayne]

Closeup of the end of the Kreutz comet from spaceweather.com.

 

[MeteorWayne]

Another comet on the toasty path...again, this insertable animation from spaceweather.com

Interestingly, I don't see it on the C3 loop, at least I don't think so. Looking very closely at the C3 images at 2042 and 2118 on the 9th, it may just be there very close to the occulting disk with no tail, but it could just be noise from particle hits. It first appears on the C2 image at 2130 on the 9th with a well developed tail, so I suspect it came in right behind the occulting disk support on the C3 image so couldn't be seen. On the C2 it had crossed the field and vaporized by 0430 on the 10th so was only visible for 7 hours.

To look closely go to http://sohodata.nascom.nasa.gov/cgi-bin ... ie_theater and select April 9th as the start date and April 10th as the end date, or if you look soon enough, you can just select the last 50 images.

 

[3488]

Thanks Wayne,

I'll have a go at some stills later for you.

Andrew Brown.

 

[MeteorWayne]

Mercury is briefly visible as it approaches inferior conjuction. It appears on the left edge on the 24th, moving faster than the stars; as it's becoming a thinner and thinner crescent (currently only 0.4% illuminated) it's getting faint real fast.

http://soho.esac.esa.int/data/LATEST/current_c3.gif

 

[EarthlingX]

Mercury is briefly visible as it approaches inferior conjuction. It appears on the left edge on the 24th, moving faster than the stars; as it's becoming a thinner and thinner crescent (currently only 0.4% illuminated) it's getting faint real fast.

http://soho.esac.esa.int/data/LATEST/current_c3.gif

This link gets updated all the time, so if you want to show it to us, you have to save it to your disk, and then upload it somewhere.
I checked SOHO images for 24th, but have not seen, or recognized Mercury. If you tell me the precise time interval, i will make a video clip and upload it to YouTube.

There is something in the upper left corner on LASCO C2 2010/04/24 22:06, but only one image.

Ah C3 .. i go check ..

 

[MeteorWayne]

If you go to the SOHO movie theatre and put in Apr 24 as the start date and Apr 26th as the end date you can see it.

I post this stuff in real time as it's happening, but will give start and end dates in the future.