It’s the End of the World…

LTA (12/23/2019) The Big Chill? Or the Big Crunch? #stars #planets #galaxies

Participate live on Monday, December 30, 2019 at 8 pm et..  Our Challenge questions will be about the January 2020 issue of Sky & Telescope magazine.


  1. In order to make his Theory of General Relativity compatible with the model of a “static” universe (which means the universe would be basically unchanged forever) Albert Einstein had to invent a mathematical term. QUESTION: What is the name of that term? ANSWER: Cosmological Constant WINNER: @euromaestro
  1. By 1929, Edwin Hubble discovered something about the galaxies that seemed to disprove the static model of the universe. QUESTION: What did Edwin Hubble discover? ANSWER: most galaxies are receding, moving away from us. Winner: @TedsScope


  1. Imagine a cubic meter.  A block shape square on all six sides.  Imagine that cube of space had just exactly 10 Hydrogen atoms in it. That much mass in that volume of space has a name. QUESTION: What do astrophysicists call the idea that the whole Universe would have, on average, this ratio of matter to space? This average of Ten Hydrogen atoms in a cubic meter of space through out the Universe is the tipping point that may decide Bill Chill or Big Crunch! ANSWER: Critical Density WINNER: @DDriving


  1. QUESTION: What kind of spatial geometry corresponds with a universe that has exactly Critical Density? ANSWER: Flat spatial geometry. Universe would expand slower and slower but never stop expanding,   A Flat Universe would be infinite in expanse and have an infinite number of galaxies and stars. WINNER: @ Euromaestro WINNER: @TShigeno


  1. QUESTION: What do we call the model of the Universe with density that is greater than Critical Density? ANSWER: Closed Universe.  The Universe would slow its expansion rate, then collapse until there was a reverse Big Band and everything becomes a small, dense, hot mass. WINNER: @TShigeno


  1. Okay, this question is about the Open Universe model, but that’s not the answer. QUESTION: Who discovered the Open Universe model, as well as the Closed and Flat models? ANSWER: Alexander Friedman.  He did this by solving the equations of Einstein’s general relativity. Friedman’s work “On the Curvature of Space” was submitted in 1922. Friedman died in 1925 at the age of 37 years. WINNER: @elle_nzau


  1. QUESTION: What’s the name the alt rock group that released the song “Endgame” on the album Out of Time. This song was playing during parts of this broadcast. ANSWER: R. E. M.  WINNER: @elle­­_nzau


Participate in the next live Periscope broadcast of “Let’s talk astronomy” on Monday, December 30, 2019 at 8 pm et.

The Challenge will be about the January 2020 issue of Sky & Telescope magazine.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s