[Saturn image credit: NASA / JPL / Space Science Institute / GordanUgarkovic]
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Where I’ll be doing things you can watch and listen to or read about
[Not everything with Crash Course Astronomy went smoothly. Credit: CCA]
For something I’m working on I needed to see where the numbers stand for Crash Course Astronomy, the web series I did back in 2015/16 with Hank Green’s group. As of the end of March it has had 41.5 million total views, which is rather staggering. That’s a 10% increase over the 37.6 million it had in October last year, which is pretty dang good for a series that ended three years ago!
There were 46 total episodes, so its possible it’ll get 46 MM total views by the end of 2019. That’d be 1 million per episode on average, and that would greatly please me.
Pic o’ the Letter
A cool or lovely or mind-bending astronomical image/video with a short description so you can grok it
When you use a telescope, the two things you care about most are light gathering and resolution. Light gathering just means how big you primary optical device (lens or mirror) is; it’s like a bucket in the rain, and a bigger bucket collects more rain. For a telescope, more light gathering means you can see fainter objects.
Resolution is trickier. It’s really the ability to distinguish two objects that are very close together. This scales with the primary size, but there are a lot of complicating factors. The biggest is the Earth’s air. It’s nice that we can breathe and all, but it’s a pain because it roils and boils and moves above us. That distorts incoming light and blurs objects — astronomers, confusingly, call this seeing. All things being equal, it limits how much resolution you can get, and it doesn’t matter how big your ‘scope is, it won’t see any finer detail.
But sometimes the air is kind, and is steadier. That can allow you to pump up the telescope’s magnification (which a lot of first-time telescope buyers fret over, but which old hands know better than to worry about due to seeing). There are various ways to do this; it helps to start with a big ‘scope, but you can add on a special piece of equipment called a Barlow Lens to increase the magnification by a factor of 2 or 3.
Astronomer Christoph Kaltseis with the astronomical equipment company Baader Planetarium did just that recently, and, viewing from his home in Austria, pumped up the volume on his 14” Celestron telescope hugely. He took a high-resolution 4k/30 frames per second video of the Moon, and the results are just freaking spectacular.
Yegads. You can see the air blurring things just a bit, but if you watch carefully you’ll see flashes of even sharper seeing. I’d be triumphantly yelling my head off at the screen if I got footage like this!
I was also very pleased to see Reiner Gamma, the “Lunar Swirl”, move into view about a minute into the video. I wrote about seeing this myself and the science behind this weird feature on the blog. But you also see craters with cracks in their floors, buried craters flooded with lava, mountains, mare, and more. Just breathtaking.
Now that it’s starting to warm up outside I’m hoping to spend some quality time with my own ‘scope again. Colorado spring tends to be windy, so we’ll see. But I do miss surfing over the Moon’s surface. Soon.
What I’ve recently written on the blog, ICYMI
[M61 is a beauty, ain’t it? See Thursday’s post for more. Credit: ESO ]
Monday March 25, 2019: The largest asteroid impact since Chelyabinsk exploded harmlessly over Bering Sea
Tuesday March 26, 2019: ALMA sees 100,000 stellar nurseries in nearby galaxies
Wednesday March 27, 2019: The White House wants NASA to put boots on the Moon by 2024. That seems... unlikely.
Thursday March 28, 2019: Facing the incomprehensible beauty of M61
Friday March 29, 2019: Hubble watches as an asteroid starts to tear itself apart
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