Astronomers have found two different – and mutually exclusive – values for the expansion rate of the universe.
The historic encounter gave us our first close-up look at a Kuiper Belt object, the most distant body we have ever explored.
Objects briefly seen on television over 50 years ago make terrific targets for today’s amateur astronomers.
Transient treasures of word and art show that our science has a rich and colorful past.
After 15 years exploring the Red Planet, the Mars Exploration Rover mission has ended.
From the start, this company’s goal was the perfect telescope.
Sky this Month
StarDome and Path of the Planets
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