Explanation: For the planned operational orbit of Chandra, the closest approach to Earth and the most distant point from Earth will be as follows: Altitude at Perigee (closest approach) = 10,000 km = 6,214 (statute) mile = 5,400 nautical mile Altitude at Apogee (most distant point from Earth) = 140,000 km = 86,992 (statute) mile = 75,594 nautical mile For reference, Mean radius of Earth = 6,371 km = 3,959 (statute) mile = 3,440 nautical mile

Explanation: For the planned operational orbit of Chandra, the closest approach to Earth and the most distant point from Earth will be as follows: Altitude at Perigee (closest approach) = 10,000 km = 6,214 (statute) mile = 5,400 nautical mile Altitude at Apogee (most distant point from Earth) = 140,000 km = 86,992 (statute) mile = 75,594 nautical mile For reference, Mean radius of Earth = 6,371 km = 3,959 (statute) mile = 3,440 nautical mile

Chandra flies 200 times higher than Hubble - more than 1/3 of the way to the moon!

Explanation: If we assume conservatively that a cluster extends out to a radius of 1 Mpc, then it has a diameter of 2 Mpc, or 6 million light years.

Explanation: If we assume conservatively that a cluster extends out to a radius of 1 Mpc, then it has a diameter of 2 Mpc, or 6 million light years.

Chandra can observe X-rays from clouds of gas so vast that it takes light five million years to go from one side to the other!

Explanation: According the CXC Observatory Guide , it takes Chandra 31 minutes to slew 90 degrees. It takes the minute hand on a clock 15 minutes to slew 90 degrees.

Explanation: According the CXC Observatory Guide , it takes Chandra 31 minutes to slew 90 degrees. It takes the minute hand on a clock 15 minutes to slew 90 degrees.

During maneuvers from one target to the next, Chandra slews more slowly than the minute hand on a clock.

At 45 feet long, Chandra is the largest satellite the shuttle has ever launched. See also: Top 10 Facts Infographic

6 If Colorado were as smooth as Chandra's mirrors, Pikes Peak would be less than one inch tall!

Explanation: Numbers:

Assume optics size = 84 cm

Assume rms low frequency figure errors are < 100a = 1e-6 cm

Assume size of Colorado= 600 km = 6 E7 cm

Then the ratio of the (rms errors)/(optics size) < 1.2 e-8

Assuming that there will be one 3 sigma peak in 1000 trials (the approx. number of measurements of the figure), then the ratio is < 3.6e-8.

Then the largest mountain (which is not Pikes Peak, but is not much taller than Pikes Peak) in Colorado would be < 2.2 cm < 1 inch.