Observation Log - May 11, 2001

Observation Log - May 11, 2001 - Tinton Falls, NJ

[NOTE: An interesting night, despite the bright moon that rose around midnight. Temperature at dawn was 52F, with little breeze during the night. There were some clouds during the session, but no dew. Took twilight flats in the morning after the session was over. Went back to the "standard" configuration on the 12" Meade LX200: Crayford focuser/f3.3 reducer/1.25" visual back/MX516 camera, and no IR nor deep sky filter. The polar alignment refinement done the other night was well worth it. Tracking was great, and GOTO was much more accurate. -GW]

3C273. Here's my first attempt at capturing the image of a quasar. This one is known as 3C273, the brightest quasar at magnitude 12.8. (The quasar is very near the center of the image. It is the left-most star of the roughly equally bright pair at the center.) This object is in Virgo at 12h 29m 06s; 02:03:07. This quasar was identified as such in 1963 by Martin Schmidt. 3C273 is moving away from us at 16% of the speed of light (48,000 km/sec) and assuming a Hubble constant of 75 km s(-1) Mpc(-1) would be at a distance of about 2.5 billion light years! That would imply an absolute magnitude of - 26.1, which gives the quasar a luminosity 2 trillion times greater than that of our sun! The quasar shows an angular diameter of less than 20". My image was created by choosing the best 25 images from a set of 42 taken between 10:06 and 10:56 pm the evening of May 10th. Thus the total integration time was 25 minutes. The images were calibrated with flats, darks and bias frames, but the only processing enhancement was a contrast stretch.

Another thing that makes this object interesting is a jet coming out of the quasar at about the 4 o'clock position. Here is an image by the 4-meter Mayall telescope that clearly shows the jet. And here is a highly-stretch version of my image. If you use a little imagination and are a generous person, you might believe that the jet is suggested in my image. I think, though, that a 16" is about the minimum you would need to produce a more convincing image of the jet. BTW, the jet would be about 150,000 ly long, given the distance suggested above.

Here is NGC4448, a galaxy in Coma Berenices, magnitude 11.1, 4'.0 x 1'.5, surface brightness 11.8 mag/sq arcmin. This is a 31-minute integration, taken between 11:00 and 11:50 pm, the evening of May 10, 2001. The images were calibrated in MaxIm with darks, bias frames and flats. Then the images were combined, then I used a "flatten background" filter, a Digital Development filter (FFT, low-pass, medium), and finally a contrast stretch. There are at least a half dozen other fainter galaxies in this field, none of which I could identify with my current software package.

This image of NGC7008 was taken on the 12" LX200 with my MX516 camera. This was made from 49 one-minute images, combined in MaxIm after calibration. Then the image was resampled to double the image scale. The photo was processed with a "flatten background" filter, a Digital Development filter (FFT, low-pass, mild), and finally a contrast stretch. NGC7008 is a planetary nebula in Cygnus, magnitude 12.0, dimensions 1'.4 x 1'.1, with a central star of magnitude 13.2.

Probably the most interesting object I caught during this session was Pluto. This picture is an animated GIF image. Look down in the bottom left corner, and you'll see Pluto, skipping back and forth. This image was made by blinking two, 10-minute exposures. The first ended at 3:41 am and the second ended at 5:00 am, so you are seeing Pluto's motion over an hour and twenty minutes. Pluto is in Ophiuchus right now and is only magnitude 13.8. Pluto's diameter is .14 arc seconds, and distance is 29.5 AU, or 4409 million km. Light takes 4 hr, 5 min, and 5 sec to reach us from Pluto right now.

(See folks, the advanced CCD imaging workshop at NEAF paid off for me!)