Orpington Astronomical Society

Astronomy => Alerts! Questions? Discussions... => Topic started by: Whitters on Aug 17, 2002, 18:25:00

Title: Asteroid Close approach Tonight (Mag 9)
Post by: Whitters on Aug 17, 2002, 18:25:00
(http://www.paul.whitmarsh.btinternet.co.uk/Astronomy/SPA_Newsletters/Asteroid-NY40.jpg)
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Rick on Aug 18, 2002, 04:45:00
There's an article on CBBC news too:

http://news.bbc.co.uk/cbbcnews/hi/sci_tech/newsid_2199000/2199726.stm
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Mike on Aug 19, 2002, 01:13:00
Well I was out at around 1am looking for it for an hour and couldnt see a darn thing ! Anyone else have any luck ?
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Ian on Aug 19, 2002, 03:51:00
I tried earlier in the evening, but the clouds made me decide that I was probably on a hiding for nothing, so I got some beauty sleep instead. Apparently I could do with as much as I can get, although I can't see why myself...
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Whitters on Aug 19, 2002, 07:34:00
As predicted pretty duff weather, Tried until 1:30 but could not get a decent shot.

Title: Asteroid Close approach Tonight (Mag 9)
Post by: Rick on Aug 19, 2002, 18:14:00
Yeah. Thin high cloud (and some patches of thicker stuff too) reduced the visual limiting mag to about 3, and the binocular limiting mag to not much better. Not much chance of seeing a mag 9 object... :sad:
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Ian on Aug 19, 2002, 18:29:00
this was posted on QCUIAG. This is not my work, credit goes to a guy called Gene Chimahusky in Philadelphia, USA.

(http://212.104.156.50/oas/2002ny40.gif)
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Rick on Aug 19, 2002, 20:26:00
That's an impressive animation.Does he have a website? Anything else like that on it?
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Ian on Aug 19, 2002, 22:39:00
As requested;

http://www.geocities.com/lynol1000
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Rick on Aug 20, 2002, 02:47:00
Hmmm... "The web site you are trying to access has exceeded its allocated data transfer." so it must have some good stuff on it... :wink:
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Whitters on Aug 21, 2002, 05:23:00
Fantastic images, jammy b****R's with decent skies.
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Whitters on Aug 21, 2002, 05:27:00
Ian, did you see what this chap used for his images, Water cooled Toucam. WOW!
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Ian on Aug 21, 2002, 05:38:00
I know some of the guys are using water cooling. I thought about it for a little while and started coming up with details like pumps, hoses, tap water on the primary, electric shocks and the weight of water hanging off my scope. I think a peltier is more appropriate  :smile:
While we are discussing QCUIAG, there is a French chap called Etienne who has done some amazing photos with a Vesta Pro. Check out his veil nebula. http://www.astrosurf.com/astrobond/ebcipr.htm
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Whitters on Aug 21, 2002, 05:57:00
Good grief!
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Anonymous on Aug 21, 2002, 06:02:00
Hi everyone, Gene Chimahusky here, the water is used to cool the hot side of the pelt, and yes, it is heavy! Using fan saw +20C from ambient hot, -10C cold in the chamber. With water I see -22C in the chamber from water temp, just add ice :smile:

Have a great day everyone!

Gene
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Mike on Aug 21, 2002, 06:24:00
Those pictures are truly fantastic - Of course you have to take into account he is using an LX90 and a Takahashi !! They are some of the best I have seen yet for the Vesta or Toucam.

(I must fix mine... I must fix mine... I must.....)
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Ian on Aug 21, 2002, 16:46:00
Hello Gene, welcome to OAS.

sorry, I should have refreshed my memory about your kit. Your mount is a alot more robust than mine so I guess weight is a less of a concern.

You've got me thinking now, is -22 significantly better than -10 or is it a case of diminishing returns?
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Anonymous on Aug 21, 2002, 19:49:00
Hi Ian,
Thanks for the welcome!
With the particular CCD in the cam, at about -10C and less absolute(not from ambient) the number of hot/warm pixels just about goes to 0. The use of a fan took it to -10C from ambient, so a 20C day only gave me a 10C cam. With water, 20C ambient and 10C water gives me -12C inside the chamber. If it is 25C ambient it starts to struggle a little , but I still get -10C absolute inside the chamber, for a -35C differential from ambient. The difference between -5C and -10C absolute is amazing and for the way I use it only requires a flat frame correction and no dark subtraction is necessary.

Gene
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Ian on Aug 21, 2002, 21:05:00
well that explains the trouble you've gone to! Here, we're lucky to get ambients over 20 at night in summer, it's usually in a region of 15. What we do have plenty of at the moment is dew. Do you get condensation on the outside of the window?

p.s. feel free to register :wink:
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Greg on Aug 22, 2002, 00:56:00
Nice to hear from the State of the People in the US.

Drop in again
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Anonymous on Aug 22, 2002, 02:46:00
Greg, thanks, I will!

Ian, I did have quite a dew prob on the window, even with a bag of dessicant in the Tadapter tube between the window and focal reducer.
I did two things about it, the first was position the window farther up the Tadapter tube and second was built a nichrome wire heater for the Tadapter tube of about 2.5 watts. Moving the window forward about 18mm seems to have fixed it and until now I have not needed the heater, but it has not been exceptionaly bad dew wise, even though the humidity has been high.

I got so frustrated with the dewing on the window that I would just give up when I cleared it with a hair dryer (and also dry'ed the bag of dessicant) more than twice, because the clearing only lasted for <10 minutes.
Title: Asteroid Close approach Tonight (Mag 9)
Post by: lynol1000 on Aug 22, 2002, 02:53:00
I registered as lynol1000, thanks for the invite Ian.

BTW: Added a little more science to my web page on the flyby. Photometry and positional info from GSC2.2 that for stars that had a Vmag. This was added to a new version of the composite made from the frames from the gif animation.
http://www.geocities.com/lynol1000/2002_ny40_08172002/index.html

Gene
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Rick on Aug 22, 2002, 05:18:00
Interesting analysis, Gene. :wink:
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Whitters on Aug 24, 2002, 15:22:00
Gene those are superb images. I must get my Toucam modified.
Title: Asteroid Close approach Tonight (Mag 9)
Post by: lynol1000 on Aug 26, 2002, 11:11:00
I am so plagued with light pollution that I lose a lot of dynmaic range trying to get 'pretty' pictures, but as a platform for digging thru the light pollution I can get some pretty deep things.

Now, for the full capabilites of the cam thru its full dynamic range, check the site Ian pointed at Etienne site:
http://www.astrosurf.com/astrobond/ebcipr.htm

He has just posted a new M57 image to yahoo egroup QCUIAG that is amazing (along with his Veil neb shots) !

Gene
Title: Asteroid Close approach Tonight (Mag 9)
Post by: Rick on Sep 13, 2002, 19:14:00
Did anyone else see the images from the William Herschel Telescope of the encounter?

http://www.ing.iac.es/PR/press/2002NY40.jpg

http://www.ing.iac.es/PR/press/2002NY40.gif

They're from the September 4th PR on http://www.ing.iac.es/PR/