Astro Bob blog update / Outside My Door

Astro Bob entries on the Duluth News Tribune website today (Oct. 9).

Before I share sky events I wanted to update you about the Astro Bob blog. I started writing it Feb. 2008 when I was a photographer and photo editor at the Duluth News Tribune. It became part of my daily work and contribution to the website. When I retired in 2018 I continued writing the blog as a freelancer for the newspaper, for which I'm grateful.

Recently, the blog was transferred to a new weblink where you can read the current entry and the full archive back to 2008. But there's a caveat. Not long ago, the newspaper website changed from free access to a paid subscription. Those of you who've tried to read the blog recently may have run into the "paywall." 

With a digital subscription you can read Astro Bob anytime you want. Without one, access is limited to three visits a month. For the time being you'll still be able to read the blog on Blogger, Facebook and Twitter for free, but that will come to an end soon. I'm a journalist at heart and fully understand and support paying for news especially when "hard copy" newspapers are on their way out. 

Of course, there's a downside.

I fear that the cost of a subscription for out-of-state readers whose key interest is reading the blog will mean I won't be able to share astronomy news as widely as previously. You're all friends, and I don't want to lose you, but this is the reality for now. I'd love it if everyone got a subscription ($100 / year) but completely understand if you feel you can't afford it. I will still post the link to the above social media sites, but if it's your 4th visit in a month you'll get a screen asking you to subscribe.

My Explore the Night blog on Sky & Telescope.

I also write a biweekly observing blog for Sky & Telescope's website with free access to current articles and the archives. You'll find many observing projects there especially if you use a telescope. 

An airplane contrail makes a bow below the moon on Oct. 9 over Duluth. Contrails are completely natural and form when water-laden exhaust from burning jet fuel condenses in the cold air at high altitude behind the plane. A similar thing happens every winter when you see your breath or "smoke" coming from tailpipes on a cold day. Bob King

Let's get out of the house now and see what's up. That's exactly what I did this morning. Intending on going for a short walk before breakfast I stopped instead in the front yard. Above the house a beautiful airplane contrail arced like a rainbow above the trees. I could tell by its drift it would pass in front of the last quarter moon, so I waited a couple minutes and witnessed a unique "occultation" of Earth's natural satellite by a band of wispy clouds. It lasted only seconds!

A contrail briefly occults the moon this morning. Bob King

A few minutes later, as I turned down the road, a colorful "comet" appeared low in the northeastern sky to the left of the sun. The truth is my comet was a sundog with a long, straight tail. Sundogs, also called parhelia, form in cirrostratus clouds that are so high they're made of ice crystals instead of water droplets. Sunlight refracted (bent) through plate-shaped, hexagonal ice crystals that hover in the air nearly parallel to the ground creates the bright ray. Red light is refracted less strongly, so it colors the sun-facing side, while blue tints the opposite end.

A comet-shaped sundog appears to the left of the sun earlier today. Bob King

As the parhelion faded, I walked back home and ate breakfast. Nature was as sweet as my shredded wheat.