While astronomers hope Juno will help them piece together how the solar system formed, the Hubble Space Telescope has already observed the births of other stars and planetary systems. Hubble has  seen distant regions of the galaxy, peering into huge clouds of gas light years across. In those clouds, called nebulae, it has seen dense disks of gas and dust—the same type of disks that's thought to have given birth to our own solar system—showing that this planet-producing process happens throughout the cosmos. Hubble has also observed stars surrounded by disks of debris that may be swarms of comets and even evidence of Jupiter-like giant planets sweeping through such a disk.