Observation Log - April 20, 2001 - Tinton Falls, NJ

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[NOTE: Temperature was 40F, some late dew, no breeze. The setup on the 12" Meade LX200 was the Crayford focuser/f3.3 reducer/1.25" visual back/ MX516 camera, and no IR blocking filter. Had no chance to do flats and darks, so have to reuse those taken on the 15th. -GW]

NGC4017, a spiral galaxy in Coma Berenices, magnitude 12.2, dimensions 1'.8 x 1'.5, surface brightness is 13.9 mag/sq arcmin. NGC4016 is at the top right, mag 13.3, 1'.5 x 0'.8, sb is 14.0. The frames were shot between 10:08 and 11:01 p.m. the evening of April 19. This composite was made from 43 exposures for a total integration time of 43 minutes. All images were processed in MaxIm with darks, flats and bias frames, then aligned and composited. I used a Digital Development filter (FFT, low-pass, hard) and flattened the background. The image was finished with a contrast stretch.

M90, a spiral galaxy in Virgo, magnitude 9.5, dimensions 11'.4 x 4'.7, surface brightness is 13.1 mag/sq arcmin, distance is 41 million light years. The brightest of the tiny galaxies to the right (four o'clock position) is LEDA 169619, mag 17.9, 24" x 15". M90 is a member of the Virgo cluster, and extends for about 120,000 light years. The frames were shot between 11:06 and 12:03 a.m. the morning of April 20. This composite was made from 47 exposures for a total integration time of 47 minutes. All images were processed in MaxIm with darks, flats and bias frames, then aligned and composited. I used a Digital Development filter (Kernel, low-pass) and an unsharp mask (FFT, low- pass, hard). The image was finished with a contrast stretch. In this highly-enhanced version, you can see a faint asteroid at the two o'clock position. This is 2001 BW44 (RA 12:36:41 DEC +13:12:58 V MAG 17.8) which gave me a moment of excitement before I determined that it was a known object!

M91, a spiral galaxy in Coma Berenices, magnitude 10.1, dimensions 5'.5 x 4'.5, surface brightness is 13.4 mag/sq arcmin, distance is 37 million light years, and it had a diameter of about 50,000 light years. The tiny galaxy under M91 is LEDA 169578, mag 17.9, 30" x 15". The frames were shot between 12:11 and 1:11 a.m. the morning of April 20. This composite was made from 41 exposures for a total integration time of 41 minutes. All images were processed in MaxIm with darks, flats and bias frames, then aligned and composited. I used a Digital Development filter (Kernel, low-pass) and an unsharp mask (FFT, low-pass, hard). The image was finished with a contrast stretch.

M63, a spiral galaxy in Canes Venatici, also known as the Sunflower Galaxy, magnitude 8.6, dimensions 15' x 9', surface brightness is 12.4 mag/sq arcmin, distance is 24 million light years, and it had a diameter of about 80,000 light years. The frames were shot between 1:15 and 2:16 a.m. the morning of April 20. This composite was made from 46 exposures for a total integration time of 46 minutes. All images were processed in MaxIm with darks, flats and bias frames, then aligned and composited. I used only a Digital Development filter (Kernel, low-pass) and a final contrast stretch.

NGC5965, a galaxy in Draco, magnitude 11.7, dimensions 6'.0 x 0'.9, surface brightness is 13.4 mag/sq arcmin, distance is 160 million light years. The frames were shot between 2:20 and 3:22 a.m. the morning of April 20. This composite was made from 51 exposures for a total integration time of 51 minutes. All images were processed in MaxIm with darks, flats and bias frames, then aligned and composited. I used a Digital Development filter (FFT, low-pass, mild) and a final contrast stretch.

NGC6181, a galaxy in Hercules, magnitude 11.9, dimensions 2'.5 x 1'.0, surface brightness is 11.2 mag/sq arcmin, distance is 110 million light years. The frames were shot between 3:27 and 4:45 a.m. the morning of April 20. This composite was made from 66 exposures for a total integration time of 66 minutes. All images were processed in MaxIm with darks, flats and bias frames, then aligned and composited. I used a Digital Development filter (FFT, low-pass, mild) and a final contrast stretch. Image suffered a little from light dewing.