A Trio in Leo and a Bright Asteroid too!!

 Where Science and Art Intersect ...

Please excuse this deep dive into my personal motivations for astrophotography. It is important to understanding why I'm so excited by this image and its contents. 

I came to astrophotography as a visual astronomer. I got into visual astronomy due to my deep interest in science. I've had this deep interest in science most of my life. I've never been an artistically minded person (although both my parents had artistic talents). I have been involved in astronomy outreach for many years; and I get great satisfaction from sharing the cosmos with our community. Once smart devices (smartphones and tablets) started to become common place, I tried to use them as another way to share the experience at my telescope with more people. This is what lead me down the path of astrophotography. Joining the Buffalo Astronomical Association (BAA) specifically to learn how to take better pictures of space and to get access to better instruments. Somewhere along the way, this became a creative or artistic outlet that I wasn't consciously looking for. To be 100% clear, the pictures I take of space are "pretty pictures". A lot of effort is placed on enhancing the data to optimize it aesthetically (color, sharpness, contrast etc.). The Science is still an underlaying foundation, that never goes away, and is a fundamental part of the experience for me. For me, astrophotography is at the intersection of Science and Art, both make an essential contribution to the experience. 

The forecast for Tuesday April 22nd improved to indicate clear skies for most of the night. A trip to our club's observatory was not in the cards for a work night. After work, I came home and set up my rig. I had not imaged from home since October. I had to rebalance the telescope on the mount, as it had been removed during the intervening time. Setting up took a little longer than usual but was completed without any issues. Once it was dark enough, the telescope was polar aligned, calibration in PHD2 guiding software was performed, and the focus of the main telescope was confirmed, allowing for successful plate solving and autofocus routines. The target for the night was already determined to be the Leo Triplet. There was no Moon until early in the morning, Leo is well placed in the sky for many hours of imaging, and I liked the framing with the Askar FRA600 (still on loan from my friend) and the ZWO ASI2600MC Pro. I loaded the sequence that I created in advance and hit play. Everything went smoothly and I imaged until about 10:30 PM when at the Meridian. I did not take flats at start up as I knew the camera had to be rotated to get the framing I wanted. So, I came out at Meridian Flip and took my flats. Once completed, I resumed the sequence and went inside to go to sleep. I knew I would lose the target some time between 2:30 to 3 am. The sequence was set to stop capturing images around 2:50 am, park the scope, and warm the camera sensor. I got up the next morning and put my rig into the shed before work, putting everything away properly after work. I collected 150 2-minute exposures. The last 20 were in the trees. After viewing the exposures with Blink in PixInsight, I ended up with 126 usable exposures. This is the resulting image:

This image of The Leo Triplet was captured on 4/22/2025 from my backyard.

Now the exciting part (at least for me):

After processing the image, I noticed a faint streaked smudge. Having experience processing comets, I recognized that something had moved relative to the stars. When we stack an image with a comet with the image registered to the stars, we get a very similar artifact. See the images below to get a better view of the artifact and to see where in the image it is located. The first image below has two rectangles. The small rectangle was drawn around the area in the image containing the smudge/streak. The large rectangle is an Insert with a 2X magnification of the area is in the small rectangle. This was inserted with Seti Astro's Astromark signature and Insert Adder script in PixInsight. The arrow indicates the location of the smudge/streak. The second image is a crop of the insert.

My initial thought was that it must be an asteroid, and a bright asteroid too!! Now to confirm and identify the asteroid. The first step was to plate solve the image. PixInsight compares the stars in the image to a database and precisely determines the location. PixInsight refers to this as an Astrometric Solution. Once solved, another PixInsight tool was used to annotate the image (see What is it? below to see the annotated image). There it was Asteroid 8 Flora. I was very excited at this point! 

The insert shows the streaked smudge indicating an object that caught my attention. The small rectangle indicates the actual position in the image and the larger rectangle (inset is this area with 2X zoom).

A close up of the area in the insert. 

Now that the asteroid was confirmed and identified, I wanted to see how much it moved over the course of the imaging session. I opened the first and last individual subframes (subs) from the imaging session, Image 001 and Image 130 (images 130 to 150 were in the trees and were not useful). The first image was captured at 9:25 PM and the last usable image was captured at 2:33 AM. This is a duration of 5 hours and 8 minutes. This includes the time used to take flats early in the session. Only 126 subs were used to process the image due to image quality issues. That's why the integration time for the image is only 4.2 hours. I did some processing on the individual images to make them look more presentable. BlurXTerminator was used to make the star shapes better, NoiseXTerminator was used to reduce the noise, and the stretch from the Screen Transfer function was applied with histogram Transformation to permanently stretch the images. The arrows were added with Cosmic Photons' Draw Annotation script. The arrows indicate the position of the asteroid.

Image 001, the first sub captured. The arrow indicates the position of asteroid 8 Flora.

Image 130, the last usable image captured. The arrow indicates the position of Asteroid 8 Flora.

Here's an animated GIF to help show the motion.:

An animated GIF showing the motion of Asteroid 8 Flora over the duration of the imaging session.

Processing:

All pre and post processing was performed in PixInsight. Pre-Processing: All subs were visually inspected with Blink and subs with issues were removed. All light Frames, Flats, Darks and Dark flats were loaded into WBPP. Linear Post Processing: Background extraction was performed with GraXpert followed by BXT (correct only). SPCC was used for Color Calibration followed by a full application of BXT. The Stars were removed using StarXT. Starless Linear: Noise was reduced with NXT. The image was made non-linear with HT. Starless Non-linear Post Processing: Saturation and intensity were increased with CT. Exponential Transformation was used to increase intensity. The Create HDR Image script was used to compress the core of the galaxies (mask was used). The Image Blend script was used (with high pass filter) to increase sharpness. Stars Linear: The Stars image was made non-linear with Seti Astro's Star Stretch script. Stars Non-Linear: Saturation was increased with CT. Starless: Intensity, and contrast were adjusted with various applications of CT. The Stars and Starless images were combined with Pixel Math to produce the final image. 

What is it?

The Leo Triplet is also known as the M66 Group. It is a group of three galaxies in the constellation of Leo. The three galaxies that comprise the group are: M65, M66, & NGC 3628. NGC 3628 is also known as The Hamburger Galaxy. A faint tidal tale can be seen emanating from the lower righthand portion of NGC 3628. There are many more galaxies in this image, feel free to zoom in and look for tiny faint fuzzies.

Asteroid 8 Flora is in this field. It is a large, bright main-belt asteroid.

An annotated version of the image. Note asteroid 8 Flora is located in the lower left of the image.

How Big is it?

• M65 has a size of 9.8 x 2.9 arcminutes (1 degree is 60 arcminutes) on the night sky and is about 117,100 light-years in diameter. 
• M66 has a size of 9.1 x 4.1 arcminutes (1 degree is 60 arcminutes) on the night sky and is about 86,400 light-years in diameter. 
• NGC 3628 has a size of 13.1 x 3.1 arcminutes (1 degree is 60 arcminutes) on the night sky and is about 140,400 light-years in diameter. 
• Asteroid 8 Flora has an apparent size of 0.1 arcseconds and is 136 km in diameter.

How Far is it?

• M65 is located about 41 million light-years (ly) from Earth in the constellation Leo.
• M66 is located about 33 million light-years (ly) from Earth in the constellation Leo.
• NGC 3628 is located about 37 million light-years (ly) from Earth in the constellation Leo.
• Asteroid 8 Flora is 1.688 AU from Earth or about 14.04 light -minutes. One Astronomical Unit (AU) is the average distance to the Sun (93 million miles). 

How to find it?

The Leo Triplet is an excellent target for visual observation or astrophotography. To find it the it: first find the constellation Leo which is very well placed in the sky during the spring in the Northern Hemisphere. find "the Sickle" or "Backwards Question Mark", which is the front of the lion. The bright star Regulus is the handle of "the Sickle". Then find the slightly less bright star Denebola which is the tail of the lion. Moving in the direction of regulus, Chertan or Theta Leonis, is the next brightest star. It marks the hind quarters. Now move roughly in the direction of Virgo to find Iota Leonis, the lion's back leg. The Leo Triplet is about halfway between Chertan and Iota Leonis but slightly "off-line" in the direction of Denebola.

A finder chart for the Leo Triplet.

Image Details:

Capture Date: 04/22/2025

Location: Eden, NY

Telescope: Askr FRA600 (no reducer)

Camera: ZWO ASI2600MC Pro

Filter: none

Mount: Sky-Watcher USA EQ6-R Pro

Exposure: 126 exposures at 120 sec / Gain 100 / Offset 50 / -10°C each for a total exposure of  4.2 hours.

Software: NINA, SharpCap Pro, PHD2, and PixInsight

Clear Skies!

Ernie