Observatory Images

The following images are from our main 20-inch telescope using one of two cameras, a ZWO 1600MM Pro or Canon EOS 6D DSLR. Exposures were acquired by observatory visitors, W. Balmer and M. Prem, and post-processing was mainly carried out by M. Prem using SIRIL.

Monday, January 16th, 2023

Comet C/2022 E3 (ZTF), otherwise known as “the Green Comet” or “the Neanderthal Comet” is shown here, about two weeks before its closest approach, having just passed periapsis (when it is closest to the Sun). Images were observed by W. Balmer in Blue, Green, and Red filters using our science camera, and processed by M. Prem using SIRIL. Because it is nearby, the comet has a large apparent motion compared to the background stars, and keeping the telescope fixed on the comet during an imaging sequence results in star trails as seen here.

Tuesday, November 22, 2022

Processed image of Orion Nebula
Orion Nebula. This image combines 31 DSLR exposures with a total integration time of over 15 minutes, processed to bring out detail, calibrate the colors and suppress noise. Glowing gas is reflecting and re-emitting the light of bright young stars, while darker clouds of cool gas and dust frame and partly obscure the view.

Thursday, October 27

Color image of the bubble nebula
Bubble Nebula. A single massive, hot star is responsible for most of the nebula’s emission. Gas expelled from the star’s own “wind” forms the shell; the gas in the shell and in surrounding clouds is excited by light from the star and glows. About an hour’s worth of exposures in narrow band filters sensitive to emission from hydrogen, oxygen, and sulfur gas were combined to form this image. Processing was used to calibrate the colors, bring out details, and suppress background noise.
Crab Nebula. A single exposure, processed to suppress background noise and enhance contrast, reveals details within this iconic celestial object. The nebula itself is the result of a supernova explosion whose light first reached Earth in the year 1054.

Friday, October 21

The following image was obtained with our ZWO 1600MM Pro camera with a narrow-band H-alpha filter.

Monochrome image of eagle nebula through H-alpha filter
Eagle nebula (H-alpha): The eagle nebula seen in this image is an active star-forming region. The energetic emissions from its young stars cause the gas in the nebula to glow in very specific colors, the strongest of which is called H-alpha, from atomic hydrogen gas. When observed through a filter that only lets through this color of light, a significant amount of detail can be seen, from the brightly glowing gas itself as well as the dust clouds that block some of the light. This image was made by stacking 10 exposures to reduce noise and then stretching to show the detail hidden in the shadows.
Image of Saturn and Titan
Saturn and Titan. This image was created by combining short exposures to capture the planet itself with deeper exposures to be able to detect its large moon, Titan.

Friday, October 14

These images are from our Canon EOS 6D with a light pollution filter.

Image of globular cluster M13
M13. This globular cluster is composed of stars that are about 11.65 billion years old, nearly 3 times older than the Solar System! Observatory open house attendees took 5 images with a total exposure time of 11 minutes which were aligned and combined to produce the image pictured here.
Image of planetary nebula M27
M27. This target, called Dumbbell Nebula or the Apple Core Nebula, is a cloud of gas and dust expelled by a dying, Sun-like star. At its center is the remnant of the progenitor star, called a “white dwarf.” It is only about 10,000 years old, a very short time in astronomy! A certain young attendee took one 3 minute image of M27, which we post-processed using “photometric color calibration” to match the colors in the image to catalogue colors from research images, and then applied a brightness stretch and de-noising filter.
Image of planetary nebula M57
M57. The Ring Nebula was a favorite of our open house attendees, who took about 20 minutes’ worth of images of this nebula. Similar to M27, this nebula was generated by a Sun-like star that has finished fusing hydrogen into helium. The nebula is about 7000 years old. The beautiful blue center of the nebula is emission from diffuse oxygen gas left in the wake of the expanding shell of red hydrogen gas. We combined, smoothed, and then stretched the images to produce the final picture.