I took this photo of the Moon and Mars last night with my phone. It might not be the best photo but believe me when I say they were both GORGEOUS. Or better yet: don’t believe me — go out tonight and see for yourself!
Now is a great time to look at Mars. It’s unusually close to Earth in its orbit and (for the same reason) pretty much directly opposite the Sun. It’s as though it’s doing its best to be a mirror for the Sun shining back at us, so it’s very very bright. This is called #opposition.
Here’s a diagram of the positions of the planets right now from theplanetstoday.com. You can see that both the Moon and Mars are in the opposite direction as the Sun, so the Moon is close to full & Mars is bright and close. #MarsOpposition
Incidentally, this convenient closeness of Earth and Mars in their orbits is why so many spacecraft were launched toward Mars a couple months ago! #MarsOppositioncnn.com/2020/07/27/wor…
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My book in title headings and epigraphs: a thread of appreciation for some of the writers who inspired me, and whose words were one way or another apocalyptically appropriate. #EndOfEverythingBookastrokatie.com/book
Chapter 1: Introduction to the Cosmos. Robert Frost, Fire and Ice.
Chapter 2: Big Bang to Now. @ann_leckie, Ancillary Justice.
Here's a thread of reviews of #EndOfEverythingBook -- because they've honestly all been really fantastic and it makes me SO HAPPY to see how much people are enjoying my book now that it's officially out there in the world! ✨📚✨
"'The End of Everything' is a pleasure. Mack’s style is personal and often funny ... I found it helpful — not reassuring, certainly, but mind-expanding — to be reminded of our place in a vast cosmos." -@nytimesbooks
"...like an animated discussion with your favourite quirky and brilliant professor. ... If you need a moment to be distracted from everyday life and journey to the deep cosmic future, I highly recommend 'The End of Everything.'" -@newscientist
A: The end of everything! Literally! How the Universe will end, & what that might look like if we were around to see it. There are five possible scenarios covered in the book: Big Crunch, Heat Death, Big Rip, Vacuum Decay, & Bounce. #EndOfEverythingBook
Q: Do I have to have an astrophysics background to understand it?
A: Not at all! It's written for a general audience, by which I mean, I won't assume you have any physics/astronomy background. There are some cool/deep concepts in there, but it's accessible. #EndOfEverythingBook
I wanna say a little bit about math. Pandemic math, specifically.
I hear a lot of people saying that the risk of dying from COVID-19, especially when young & healthy, is *tiny*, often to justify opening universities. But a small *percentage* risk is not the only factor. (1/4)
The key thing is the difference between percent and number. When the NUMBER of people infected is low, a low risk of death means *few deaths*. But when the NUMBER of people is high, even a small PERCENTAGE is a lot of deaths. (2/4)
Let's say the disease kills 0.01% of college-age people. (It might be a bit more than that.) If the pandemic is out of control, the spread within colleges means a LOT of the 20 million college students in the US could get the disease.