Dark impact mark in Jupiters south polar region 19 July

[Keith g]

This just in all, Coutesy and Credit of Anthony Wesley, Murrumbateman, Australia at 1554UT 19 July today

http://www.acquerra.com.au/astro/ObsReport/jupiter-impact.html

Keith..

[brianb]

WOW!

And curses ... a special event guarantees solid cloud for the duration!

[martinastro]

Yikes!, that is absolutely incredible!!. This is a major event, Jupiter impacted on two occasions in our life times...thanks to the heads up on this important event Keith.

[Keith g]

Whoahoo look like clear skies tonight guys, trying to figure out at what time it transits at, assuming it will not vanish too soon, Martin, I know that you will be up for this!

Keith..

[martinastro]

Keith, this is like a dream come true for me, I never seen the SL9 scars so this is my first chance to see the effects of a comet/asteroid impact on Jupiter. I just hope I can see it visually through the scope. This is a major event, I bet the net with be exploding with activity when the word spreads. Looking forward to images and sketches from the community.

Carl, Brian, Dave...you know what to do 

Thanks again for the heads up keith.

[Keith g]

According to Dave Grennan (thanks Dave), the next transit time tonight is at 2.33BST, late I know, but remember, it's at the SOUTH pole, though I'm sure anyone looking would notice if it has'nt dissipated by then....

Keith..

[Keith g]

Again, thanks to Dave...

For the rest of the month transit times will be roughly;

(All times are BST) Amended Better times:

Just an update a better Sys II longitude is known so more precise transit times are possible

July 20 03:01; 12:57; 22:52
July 21 08:48; 18:42
July 22 04:38; 14:34
July 23 00:29; 10:25; 20:20
July 24 06:16; 16:12
July 25 02:07; 12:03; 21:59
July 26 07:55; 17:50
July 27 03:46; 13:42; 23:37
July 28 09:33; 19:27
July 29 05:23; 15:19
July 30 01:14; 11:10; 21:05
July 31 07:01; 16:56
All times are BST

Keith..

[Big Dipper]

Just come in after setting up for some imaging & heard about this news story. Well I've certainly got the skies for it but alas, not the equipment (i.e. no scope & only a set of 10X50 bins).

Still no harm in looking after 2.30am (assuming the sky is still clear).

Be great if Carl is out imaging Jupiter again at the appropriate time.

[brianb]

Amazingly the sky was clear here, I spent an hour from 0230 to 0330 concentrating on Jupiter, Io's shadow was seen in transit (dark spot in the eqautorial zone) but I did not see the "impact mark". The seeing was however rotten, so much so in fact that I took the precaution of setting up my FLT 110 as well as the CPC 1100, the FLT was giving a much less wobbly image and I did some imaging with it - maybe something will show up on them. First decent transparent sky for a long time (between occasional clouds), and it nearly went dark ... great night capped off with an astounding display of NLC!

Edit: Just finished a rough process of the red channel images; though the quality is poor because of the bad seeing, I do believe that I've captured the "impact mark" - just above the lowest part of the image below. It's at the limit of visibility I'm afraid but it's there and it's in the right position, a bit past the meridian.

2009 July 20, 0234 UT, William Optics 110mm f/7.7 fluorite triplet refractor, x4 Imagemate, Astronomik type 2c red colour seperation filter, Imaging Source DMK41 camera.

[markt]

Great image Brian, you got it there for sure.   

[John9929]

Well done Brian, I can see it no problem

[martinastro]

Excellent stuff Brian!!. Very clear on your image too and almost as large as Io's shadow.

I was obsering the shadow transit this morning and seen some great detail on Jupiter, however the seeing was too bouncy to spot the impact scar. Will try again.

Congrats again on a stunning capture!

[brianb]

Thanks guys! Here's hoping for some nice steady seeing just for a change....

[davegrennan]

Guys, the seeing was the worst ever here in Dublin last night so no images from last night. BTW thanks Keith for posting the times as I didn;t get the chance to do that.  Hopefully we'll get the chance to grab some decent imagery of it before it fades.

Martin:  You really didn't see the SL9 event in 1994?  Hate to rub it in but a few of us also got to spend a lovely afternoon in Sligo with the late Gene Shoemaker and his lovely wife in 1995.  (Reminder: to self must scan those slides of that day!).  I'll never forget it as long as I live.  I was helping out at an astronomy ireland event in Dublin.  I was setting up the scope, looked at jupiter and there was two big black eyes looking back at me, i'll never forget it.  They were like big panda eyes.  Definitely the highlight of my astronomical life.

Anyway back on topic.  Further news that JPL has now confirmed an impact event.

http://www.jpl.nasa.gov/news/news.cfm?release=2009-112

(a little dissapointed at how Anthony Wesley's contribution is played down in the above article to be honest)

Keck were looking at it today also.

What really interests me is the discussion on the nature of the impactor.  My money is on a comet.  If you look closely at Anthony's image you can see two little spots at thefour o clock position to the main spot.  This suggest to me that this was a fragmented body.  Given that the immediate around Jupiter should be pretty clear of minor planets then this all would suggest a comet or perhaps a loosly bound minor planet in a highly elliptical orbit perhaps?

Anyway thats my 2 cent.

[brianb]

What really interests me is the discussion on the nature of the impactor.  My money is on a comet.  If you look closely at Anthony's image you can see two little spots at thefour o clock position to the main spot.

Indeed ... but given that the impact mark is so large, by comparison with SL9 we're talking about a 1 Km +, possibly 2 Km diameter object; I think a "fresh" comet would have some sort of tail if it were out by Jupiter and should have been detected long since. Don't forget that, the more we look at even small asteroids, the more we find have small satellites.

The news media seem to be studiously avoiding reporting this event, not even a whisper on e.g. the science page on the BBC News site.