http://www.iflscience.com/space/you-could-fit-the-entire-human-race-into-a-sugar-cube-and-13-other-facts-to-put-the-universe-into-perspective/

http://spaceplace.nasa.gov/review/dr-marc-technology/hubble.html

http://www.universetoday.com/47898/length-of-day-on-venus/

http://www.pbs.org/wgbh/nova/space/star-in-you.html

http://www.bbc.co.uk/science/space/solarsystem/sun_and_planets/sun

http://www.npr.org/sections/krulwich/2012/09/17/161096233/which-is-greater-the-number-of-sand-grains-on-earth-or-stars-in-the-sky

https://www.theguardian.com/science/2009/apr/21/space-raspberries-amino-acids-astrobiology

http://www.nasa.gov/mission_pages/GLAST/science/neutron_stars.html

https://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/