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Questions that really don't belong in any category, even a new one...


  • What are the masses and radii of the following objects: electron, proton, earth, sun, solar system, globular cluster, open cluster, galaxy cluster.
  • What is the spatial extent of the visible universe?
  • What is the angular extent of Virgo?
  • How big is a typical globular cluster on the sky?
  • What do you know about planetary nebulae? What is their extent?


  • What is the mean local sidereal time at midnight on March 20th? (RS)
  • What is the RA of the sun at the autumnal equinox? (RS)

Brightest objects in the sky:

  • What is the brightest object in the night sky? Second? Third? (RS)
  • What is the brightest star? (RS)


  • If we go out at a clear night, how many stars can we see with naked eyes?
  • What is Vega, Sirius?
  • What is the Cygnus loop, Crab nebula? What are their angular extents? What is the dominant radiative process for these?
  • How would you define "strong gravity"?
  • How are muons created in the atmosphere?
    • What are cosmic rays? What type of particle?
  • Who was Kepler? What are his three laws? Where did his data come from? Did he use a telescope? What instruments did he use?
  • What is Alpha Canis Majoris? What two things make it special? How far is Sirius A from Sirius B?
  • What is Alpha Orionis? What kind of star is it and where is it evolutionarily on the HR diagram? How do you know it's not associated with the Orion nebula? What is their angular separation?
  • What is Alpha Ursae Minoris?
  • What is Alpha Lyrae and why is it important?