Why did the Industrial Revolution start when it did? Why did Silicon Valley happen in California rather than Japan or Boston? Human progress is understudied, and Patrick Collison and tylercowen want to change that. on.theatln.tc/mlOXOp2

I am currently 16 hrs 42 mins 42 secs of light-travel time from Earth (2019:212:000000:2L)

Thing I will never get over: just how thin Saturn’s rings are. (Image from Cassini; info here: jpl.nasa.gov/spaceimages/de…)

ow.ly/J1im50v7POQ

Conversation at the hospital yesterday: Him - You teach science? Do you know astronomy? Me - Some. I teach physics. Him - What star were you born under? Me - Um, the Sun. Him - No. What star influences you the most? Me - Um, the Sun! Him - Oh, so you don't study the stars?

I am currently 16 hrs 42 mins 55 secs of light-travel time from Earth (2019:214:000000:2L)

#FF #FollowFriday W Dr. T 🏳️‍🌈👩‍🔬 O @ReadMoreScience M @tia_martineau E @aimee_e27 N Sarafina El-Badry Nance, PhD I Algebraic Geometer N @_Astro_Nerd_ S Sophia Gad-Nasr C ☄️Ashley🔭Lindalía☄️ I @ergonightmares E EGM N @nehathemartian C @Sarah_Cosgriff E Emma Chapman

Carl Anderson identified the positron, the positively charged antiparticle of the electron, #OTD in 1932. (Fig: Anderson, Phys Rev 43, 491)

Follow the waxing Moon through the sky as we pass the midpoint of astronomical summer. skyandtelescope.com/observing/this…

Right #now Chandra is studying a pulsar in Puppis! Nearby in the sky is NGC 2440, a planetary nebula containing one of the hottest white dwarf stars known! This nebula glows as a result of fluorescence caused by ultraviolet radiation from the blazing star. #Today's Obs: 9h 10m

We'll give you a hint: The answer is 1 or 16. What do you think? via @Mashable to.pbs.org/2YGhVOy

qz.com/1680054/astron…

Happy birthday to astronaut Neil Armstrong, who was born #onthisday in 1930 and was the first human to set foot on the Moon 50 years ago. Images © NASA

Gravity might seem simple, but the more we learn about physics, the stranger it gets. In a new book, science journalist Richard Panek writes about the trouble with gravity. go.aps.org/2YIK9rV via The Washington Post

Very sad to say that in addition to the loss of Anne Nelson to a climbing/hiking accident (see my last retweet), the field has also lost Steve Gubser, in a separate incident, this same weekend. Among many contributions, Steve helped turn/launch AdS/CFT into a powerful tool. 1/2

Astro tweeps: correct me if I’m wrong, but I believe the 6.5m Clay telescope is the largest telescope on earth that can be used for eyepiece viewing? It also has a twin (Baade Telescope), & each has >7x the collecting area of the Hubble telescope. Simply astonishing sights!

cwp.library.ucla.edu/dev/86.html

T O N I G H T ! T O N I G H T ! T O N I G H T at 7 p.m.! AoT is back at Franktuary with three fun, informal talks by some your friendly local astronomers! Apologizes for short notice, Space Cadets! #aot #aotpgh #astronomyoutreach #astronomyontap