Hubble has captured vivid views of newly forming stars inside
the Orion nebula. Stars form when a cloud of interstellar
gas collapses under the force of its own gravity. Because
the cloud is spinning slowly, it leaves behind a dark disk
of orbiting debris that may well form a planetary system.
Planets are born in the spinning disks of debris left behind
as stars form. The matter in these disks gradually collects
into ever larger lumps that ultimately become planet-sized.
In the lower picture (four sections) the red dot at the
center of each object is a young star. Surrounding each
star is a dark disk of debris. About 4.6 billion years ago,
before planets formed around our Sun, the solar system probably
looked like this.