Astronomers have found evidence that galaxies are connected via an enormous cosmic web of intergalactic gas that helps many of them stay prolific star creators. Researchers studied the space between two nearby spiral galaxies, the Andromeda Galaxy and M33, which are 750,000 light-years apart and lie 2.5 million and 2.8 million light-years from Earth, respectively. As the scientists report online today in Nature, a previously known gaseous column between the two galaxies contains seven gas clouds (white blobs in the image), the largest being 21,000 light-years across. Made mostly of neutral hydrogen gas, the clouds have probably condensed from the filament of gas stretching between the two galaxies. This discovery suggests that even as galaxies turn their gas into stars, they grab more gas from their surroundings and thereby prolong their star-making careers.
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