Jets From Young Stars

When a star like the sun is born it shoots out jets of gas at speeds of more than 100 miles a second! As the jet plows into the cloud that gave it birth powerful shock waves form which sweep up the cloud material into a bow-shaped arc. Astronomers do not yet understand why the jets form but they believe the jets turn on and off or ``pulse'' with different frequencies. As the pulses move away from the star they sweep up gas ahead of them to form dense knots. The frequnecy of the pulses and density of the jet relative the cloud can really affect the way the jet looks on the sky.