BAN #191: Wanna take a SCIENCE vacation?, A comet and the Double Cluster

10 February 2020   Issue #191

[Spiral Galaxy M81 image credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona]

Subscribers know you can’t get enough science.

Upcoming Appearances/Shameless Self-Promotion

Where I’ll be doing things you can watch and listen to or read about

If you’ve been reading this newsletter for more than three seconds you know I love my home state of Colorado. The mountains, the wildlife, the geology… and, when you head west a bit, the phenomenally dark skies. This place is amazing.

If it sounds like someplace you’d like to visit, then I have good news for ya: How would you like to take not just a vacation in Colorado, but a science vacation?

[This guy will be there, as will his trusty ‘scope.]

My wife and I run a company called Science Getaways, where people can do just that. Our next trip is to the Bar Lazy J Ranch in Parshall, Colorado, literally on the banks of the Colorado River. We like ranches because the food is excellent, it’s all-inclusive, and, honestly, it’s just fun. There’s horseback riding, rafting, archery, zip-lining, fishing, a heated pool… all optional, so you can be as active or inactive as you’d like. And you’ll meet like-minded science enthusiasts (you know: nerds) and have a week away from it all.

But: Take your brain. You’ll need it.

We’ll take hikes with geologist Dr. Holly Brunkal who will answer all your Earth questions, and I’ll be answering the ones from there on upward. In fact, star-gazing is a major part of this vacation! I have a Celestron 20-centimeter ‘scope, and we’ll use it to look at planets — Jupiter, Mars, Saturn, Uranus, and even Neptune will be visible all week! — as well as Galactic treasures like planetary nebulae, emission nebulae, star clusters, and a couple of other galaxies, as well. The skies there are dark, and if you’ve never experienced truly dark skies, well, there’s no describing it. It’s awe-inspiring, in the truest sense of that phrase.

[“Star Gazers”, taken at a recent Science Getaway to Latigo Ranch in Colorado. That night we saw the asteroid Vesta deep in the star fields of the Milky Way. I’m the guy with the glowy face on the right; the light on the horizon was barely visible by eye, but shows up in this long exposure. Credit: Science Rancher Michele Wedel]

I also have a new Celestron Starsense Explorer 13-cm Newtonian reflector which I’m itching to use under a dark sky. The aiming of the ‘scope is aided using a smartphone to tell you when you’re pointing at the desired target, which is very cool. On top of that there’s also my Lunt 50 mm solar telescope — hopefully, by this summer the Sun will be showing off a sunspot or two, and some prominences and other features we can view. Seeing these on the Sun (safely!) with your own eyes is an amazing experience.

Holly and I will also be giving talks about current topics in science — she studies landslides and volcanoes, so you know that’ll be exciting, and I have two brand new never-before-given talks I’ll be presenting, too. Every year the one thing guests want more of is talks, so we’re obliging.

Interested? CLICK HERE. And I hope to see y’all there!

Pic o’ the Letter

A cool or lovely or mind-bending astronomical image/video with a short description so you can grok it

Whenever I post a picture of a comet, it’s either very close up (like Rosetta images of 67P), Hubble or other grand observatory shots, or “amateur” astronomy images showing just stars scattered in the background.

So I was surprised to learn that the comet C/2017 T2 (Pan-STARRS) recently past by one of my favorite observing targets in the sky: The Double Cluster!

[Credit: Adam Block]

That shot is by my friend Adam Block, who took it using a Takahashi Astrograph (a telescope designed to take sharp pictures with) on Mt. Lemmon, Arizona. The comet is glowing a lovely shade of green, due to molecules of diatomic carbon (C2), which is pretty common for comets.

As for the Double Cluster, the name is pretty obvious. It’s two stars clusters very close together in the sky in Perseus, about a half a degree from center-to-center. They’re easy to see in binoculars (if you think of Cassiopeia as a W, the second and third stars from the left point right down to it toward Perseus), and through even small ‘scope at low power their characteristics are obvious. It’s actually tougher to see them through bigger telescopes because it’s hard to see them both at the same time!

The official names for the two are h and Chi Persei (Chi is to the left in Adam’s shot) and they’re both about 7,600 light years away. That part of the sky is right in the plane of the Milky Way, and when I found the distance my first thought was that it’s amazing we can see them at all. There’s a lot of dust and gas in that direction, and that blocks distant objects. It turns out they are dimmed, by just under 2 magnitudes (a factor of about 6). If there weren’t any dust between us and them they’d be easily visible to the naked eye, and easily split too. That would be amazing.

At that distance, their separation puts them at about 60 - 70 light years apart/ What a view each must have of the other! That would be pretty cool.

[The orbit of 2017 T2 in the inner solar system, and its position when Adam took his image. Credit: NASA/JPL-Caltech]

Our view from here is pretty nice, too. It’s coincidence that the orbit of the comet brought it so close to the clusters, but they make a nice trio. The comet was over 230 million kilometers from Earth when Adam took this shot. Knowing how far north Perseus is, I wasn’t surprised to find out the comet’s orbit is highly tipped (nearly 60°) to Earth’s orbit. It’s a long-period comet, and by long I mean long: It takes about 560,000 years to orbit the Sun!

The orbit is incredibly elliptical, nearly a straight line, taking it as close to the Sun as about 250 million kilometers, but as far out as well over a trillion! So gawk at images taken of it while you can: It won’t be back again for quite some time.

Blog Jam

What I’ve recently written on the blog, ICYMI

[The star HD 101584 is dying, and blowing out a wind of gas that is forming a decidedly odd and very cool shape. From Wednesday’s article. Credit: ALMA (ESO/NAOJ/NRAO), Olofsson et al. Acknowledgement: Robert Cumming]

Monday 03 February, 2020: Citizen scientists discover a new type of aurora: Dunes

Tuesday 04 February, 2020: A dead star's spin is dragging the fabric of spacetime along with it

Wednesday 05 February, 2020: HD 101584: A binary star casts out a bizarre hourglass of gas

Thursday 06 February, 2020: A huge distant galaxy went from making billions of stars to suddenly stopping. Why?

Friday 07 February, 2020: Yo, I heard you like galaxy collisions so I put a galaxy collision in your galaxy collision

Et alia

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