Greenhawk Observatory

07/21/2026

I just relaunched the Greenhawk Observatory website
After a lot of late nights, the clear kind and the cloudy kind, I've rebuilt my astrophotography site from the ground up, and I'd love for this community to be among the first to explore it.
What's new:
Reprocessed images. I've replaced older shots with newer, better-processed versions throughout the site.
A much bigger gallery. Over 80 pages of content on deep-sky and solar-system objects, with the details and stories behind each one.
Full-screen viewing. You can now expand any image to fill your screen and really see the detail.
A completely redesigned Messier Catalog. A brand-new look and feel for the interactive PDF version of all 110 objects.
Refreshed downloads. Updated pages with new presentations to grab.
New talks. The video gallery now includes several new astronomy talks.
It's all free to explore and genuinely a labor of love for this hobby. If you have a few minutes, take a look and tell me what you think. Feedback from fellow observers means a lot.
Clear skies,
Chanan, Greenhawk Observatory
https://www.greenhawkobservatory.com/

05/24/2026

This is my first attempt to create a composite image of the Moon as well as bringing out mineral color data.
The image was captured in two sessions. The moon image is a 1 minute video of over 3000 frames. Stacked in Autostakkert using 300 best frames and then stretched in Registax and contrast fix in Photoshop. The color version, is the same image heavily color saturated in multiple small increments. No color was added, just slowly eked out in 10-15 steps.

Since the moon is thousands of times brighter than the background stars, those were imaged separately. 1 hour exposure, stacked in PixInsight and then combined with the moon in Photoshop.
All imaged through a Takahashi 90mm Telescope.

The mineral colors meaning is explained below:
Deep Blue is Titanium-rich basaltic maria, Cyan-Blue is Iron-rich volcanic plains, Purple is Mixed basalt/ejecta composition, Bright white / blue is Fresh crater ejecta, Dark Grey / Green is Mature mare basalt and Orange / Tan are the Feldspathic highlands which are rich in aluminum and calcium rich rocks.

Let me know what you think.

05/20/2026

This is a 5 hour exposure taken with a Takahashi 90mm scope and the ZWO ASI 533MC camera of the Coma Galaxy Cluster also cataloged as Abell 1656. It is one of the richest and galaxy clusters in the nearby universe. Located about 320 million light-years from Earth in the constellation Coma Berenices, it contains more than 1,000 confirmed galaxies and potentially several thousand members when faint dwarf galaxies are included. The cluster spans roughly 20 million light-years and is dominated by giant elliptical galaxies rather than spiral systems like our own Milky Way. It was first recognized as a dense concentration of “nebulae” by 18th and 19th century observers, but its true nature as a gravitationally bound cluster of galaxies became clear in the early 20th century.

At the center of the cluster are two enormous elliptical galaxies, NGC 4874 and NGC 4889. NGC 4889 contains at least 100 billion stars and extends to nearly one million light-years across when its diffuse outer halo is included, roughly ten times the diameter of the Milky Way. It also hosts one of the most massive black holes ever measured, with an estimated mass of about 20 billion times that of the Sun.

In 1933, Swiss astronomer Fritz Zwicky measured the velocities of Coma galaxies and found they were moving so fast that the visible matter could not provide enough gravity to keep the cluster bound together. He concluded that most of the mass was invisible, which he called “dunkle Materie” or dark matter. Modern studies confirm that about 85 percent of the cluster’s mass is dark matter, with only a small fraction is stars and gas. Zwicky’s work on the Coma Cluster provided the first compelling evidence that the universe is dominated by matter we cannot directly see, a discovery that transformed cosmology.


The attached images include a finding chart showing in red the field of view. There are two versions of the annotated image, the one including NGC, IC and PGC catalogs is a little overwhelming. Recommend viewing this zoomed in to 100%.

04/04/2026

Last night I decided to see if I could track the Artemis II mission with my telescope.

Using my Takahashi Sky 90 with the ZWO 533MC camera I was able to capture 201 exposures of 10 seconds each which I converted to a movie. The 40 second movie captures 35 minutes in actual time.
It was a moving experience, watching the screen refresh every 10 seconds, watching how that point of light progressed on the background of the infinite void and background stars, knowing there are 4 astronauts inside that point of light heading for the moon.

I also stacked and stretched the 201 images to show the streak / motion of the capsule as it moves through space. Images were taken between 2:11 AM and 2:57 AM last night pacific.

Going to try and see if I can get it visually as well with my 12".
Fun experience.

04/01/2026

Take a beat from the insanity all around. For the first time since 1972, if all goes well, humans will be leaving Earth's orbit at 6:24PM ET and will orbit the moon as part of a series of missions that will lead to the first moon landing in over half a century.
“Astronomy compels the soul to look upwards and leads us from this world to another.” Plato, 360 BC
Watch it live on YouTube or your favorite news station.

This live feed from our Kennedy Space Center in Florida will provide continuous views of the Artemis II Moon rocket beginning on Thursday, March 19, with rol...

03/07/2026

First Light with Takahashi Sky-90 telescope
This is the first image I have taken with this scope. 4 hours and 48 minutes of M78, taken on March 5&6.

02/13/2026

New Image: The Crab Nebula
In the year 1054 a new star appeared in the sky. For 23 days it was visible even in daytime, and at night it remained visible for nearly two years. It was carefully recorded by Chinese astronomers and likely noted by Indigenous peoples in North America.
That was the supernova of a massive star located about 6,500 light years away. Which means that roughly around 5400–5500 BCE, that star exploded in a Type II supernova, and it took over 6,500 years for the light of that explosion to reach Earth and suddenly blaze in our sky.
Today we call it the Crab Nebula.
The nebula is the expanding remnant of that explosion. And at its heart sits a pulsar — a neutron star about 1.4 times the mass of our Sun, compressed into a sphere only about 20 kilometers across, roughly the size of a city. It spins around its axis 30 times per second, sweeping beams of radiation across space like a cosmic lighthouse. Its radio pulses were first detected in the late 1960s, confirming the incredible physics at the core of this ancient explosion.
The image was taken with a 26 year old Celestron C-8 scope at it native 2000mm focal length, on an AP900 Mount with a ZWO ASI533MC camera (no filters). 80 minute exposure. It really needs longer to bring out more of the details.

02/09/2026

First light - working to refurbish a 26 year old C-8 SCT. Still work in progress. This is a short exposure taken last night.