Jedolby

  Let me just say right up front that 2025 was a very difficult year for me, personally. It may have been even worse than the year of the COVID-19 pandemic. But I won't go into the details of why 2025 was so horrible for me. This blog is not about my personal life. It's about my life as a backyard astronomer. And ironically, even though 2025 was lousy in many respects personally, it turned out to be my best year of astronomical imaging. In my first blog of 2025, I gave a report of my imaging performance in 2024 . It was pretty good. At least I got as many imaging nights (282) in 2024 as I got in the previous year. And I found 5 supernovae in 2024, which was an improvement upon the 4 that I came across in 2023. But 2024 was my fourth year in a row in which I wasn't able to achieve 300 nights of imaging. It seemed that my current location in Tucson was not as good for astronomy as my old house on the west side. After all, in each of the years from 2017 to 2020 at my former re...

[Reader Challenge: In the text, I've included 7 phrases from George Harrison's When We Was Fab . Can you spot them all? Answers at bottom of page.] Out between the orbits of Mars and Jupiter lies the "planet that should have been." But it never formed, because of Jupiter's powerful and chaotic gravitational influence in the region. Instead of a single planet that ought to exist there, according to the 18th century law of Johann Elert Bode and Johann Daniel Titus (known as the Titius-Bode Law ), there are millions of rocky fragments that are collectively known as the Main Asteroid Belt . On January 1, 1801, Sicilian astronomer Giuseppe Piazzi discovered the first known asteroid (1) Ceres. Since then, astronomers have found more than a million asteroids, numbered in order of discovery. For many years, the naming convention of the asteroids required that they be named after goddesses, since they were considered to be "minor planets." Only the major planets...

As a supernova hunter, I spend my nights shooting galaxies. Lots of galaxies! As a matter of fact, this year, I shot over 12,000 galaxies (a record for me). And my reward for shooting 12,000 galaxies was finding 6 supernovae. Yeah, 6 supernovae per 12,000 galaxy images. Not very good odds, ay? Oh, well. Such is the life of a supernova hunter . But one of the perks of shooting so many galaxies is acquiring lots of "reference images." Of course, it's not just a perk. Accruing reference images is done more or less by design, because in order to do supernova hunting, I need to have comparison images for every galaxy I shoot. Else, how would I know if I've found a supernova in a given galaxy? I need to compare tonight's image of a galaxy with an older one to see if there are any new stars in the galaxy. As a matter of fact, it's even trickier than that! Depending on sky conditions, one night's image may not be as good as another night's image. Some of my so...

  It's unfortunate that one of the best meteor showers of the year has to occur in the cold month of December! Although I live in Arizona, where the winters are mild, meteor showers are tough because you have to be outside to watch them, and while you're out there, you're just standing there looking up, or sitting in a chair or lying on a cot. The inactivity makes you feel colder than if you were doing something. And if you don't have a chair or cot, it's kind of a pain in the neck to look up for long periods. Nevertheless, my daughter and I stood out there in our back yard for about 5 minutes looking up, and we saw about 10 meteors. For our bright, suburban skies, that's not too shabby. One of the meteors was very bright and drew an "Ohhhhh!" from both of us. After that highlight, we decided it was too cold and too painful on our necks to keep watching, so we went inside. And that 5-minute meteor gazing was a much better experience than, say, watching...

Despite all the sensational headlines you may read on the internet, Comet 3I/ATLAS remains an unremarkable object in the morning sky. My animated GIF above, taken on December 9th, shows a tiny little comet-like object moving past a background star over a period of about 7 minutes. The planetarium software that I use, Cartes du Ciel, indicated that 3I/ATLAS was around 15th magnitude. I think it looks a little brighter than that, but I have to admit that whatever its official magnitude is, 3I/ATLAS is getting a lot more attention and hype than it deserves! I didn't go to the trouble of converting pixel counts to stellar magnitudes, but the line graph feature in MaxIM DL CCD software shows that the brightness of 3I/ATLAS maxes out at around 9,100 counts. My camera has a 16-bit digitizer, so the display range for each pixel is from 0 to 65,535, with 0 representing black and 65,535 representing white. In a 15-second exposure, the brightest pixels in 3I/ATLAS are only 14% of full pixel b...