First cosmic X-ray source found outside the solar system (1962), launching X-ray astronomy.
Worth knowing about Sco X-1
You see Sco X-1 as it was about 7,600 years ago.
Why it stands out
After the Sun, the brightest source of X-rays in the sky. Finding it earned Riccardo Giacconi a share of the 2002 Nobel Prize in Physics.
What it is
A close binary where a neutron star pulls gas off a companion star and heats that gas until it blazes in X-rays.
How we know: Earth’s atmosphere blocks X-rays, so it was first found with a detector on a sounding rocket above the atmosphere; later, orbiting telescopes studied its spectrum and flickering.
Show Sco X-1 in the model
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