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Figure 11-6 RIVUXG A Circumstellar Accretion Disk and Jets (a) This is an artist’s illustration of excess outflowing material from a gas jet as this forming star is accumulating material from the surrounding disk. Astronomers are interested in this sort of object because it is probably similar to the one from which our solar system formed. (b) These Hubble images of HH 30 show changes over a 5-year period in the disk and jets of this newborn star. There is an edge-on disk (located at the bottom of the images), which appears as a flattened cloud of dust split into two halves by a dark lane, blocking light from the central star. In 1995 and 2000, the left and right sides of the disk were about the same brightness, but in 1998 the right side was brighter. These patterns may be caused by bright spots on the star or variations in the disk near the star.