Many of these were found, causing much glee among the space junkies. Their glee was soon turned to just a light joyfulness, once it was realized that the only planets they "found" were huge gas giants, the size of Jupiter or bigger. These planets do not hold promise for extra-terrestrial life.
Having found many of these planets around many many stars, it appeared that solar systems were fairly common, but no one had ever actually imaged a planet that was not one of our solar system's orbital family.
That has changed. -FUPPETS- is pleased to announce the very first image of "exoplanets," planets found outside of our solar system. The image below was taken of a very massive young star, designated HR8799, with arrows pointing at three gas giant planets orbiting it. It was taken in seven different infra-red spectra. The gas giants are thought to be at least 3 times the size of Jupiter.
The two innermost planets are the heaviest, about 10 times as massive as Jupiter, while the outer planet is the lightest, about seven times as massive. That size relationship suggests the planets coalesced from a vast disk of gas, dust and ice particles that once encircled the star. The planets reside at roughly 25, 40 and 70 astronomical units from HR 8799. (One AU is the average Earth-sun distance.) By comparison, the solar system’s most distant planet, Neptune, has an average separation of 30 AU from the sun.
Intriguingly, the HR 8799 system’s outermost planet lies just inside a remnant disk of dusty debris that hasn’t been directly imaged but is believed to surround the star.
The disk is similar to the solar system’s Kuiper Belt, which was generated by comet collisions.-Ron Cowen (ScienceNews.com)