<\/p>\n Now, scientists studying the perplexing bubbles with the U.S. National Science Foundation Green Bank Telescope<\/a> in West Virginia have discovered something shocking: Nestled deep within the superhot bubbles are gargantuan clouds of cold hydrogen gas that have inexplicably survived in an extreme environment.<\/p>\n You may like<\/p>\n According to the researchers, these bewildering clouds are likely the remnants of much larger structures that puffed out of the galaxy’s center several million years ago.<\/p>\n “Think of it like dropping an ice cube into boiling water: a small one melts quickly, but a larger one lasts longer \u2014 even as it dissolves,” lead study author Rongmon Bordoloi<\/a>, an associate professor in the Department of Physics at North Carolina State University, told Live Science in an email. “We believe these clouds may be remnants of much larger structures that are currently being eroded by the galactic wind.”<\/p>\n The discovery could indicate that our galaxy’s central black hole experienced a violent outburst of matter more recently than previously thought, Bordoloi added. The research describing the clouds was published July 7 in The Astrophysical Journal Letters<\/a>.<\/p>\n Clouds of hydrogen gas hide within the Fermi bubbles. (Image credit: NSF\/AUI\/NSF NRAO\/P.Vosteen)Baffling bubbles<\/p>\n Towering over the galactic center, the Fermi bubbles were discovered in 2010 by NASA<\/a>‘s Fermi Gamma-ray Space Telescope<\/a>. Despite being comparable to our galaxy in size, the bubbles are visible only in gamma-rays, and they overlap with an equally mysterious X-ray counterpart known as the eROSITA bubbles<\/a>.<\/p>\n These bubbles are incredibly hot, with the plasma that makes up the Fermi bubbles <\/a>reaching more than a million kelvins (nearly 2 million degrees Fahrenheit). It’s thought that the bubbles are likely the result of an ancient, violent outburst from the Milky Way<\/a>‘s central black hole, which spewed twin jets of matter above and below the galactic plane simultaneously, scooping up nearby matter in the process and flinging it outward into space.<\/p>\n The newly discovered cold hydrogen clouds may be remnants of some of that matter, according to the study authors. Spotted with the Green Bank Telescope, the cold clouds range from about 13 to 91 light-years across, making each one many times larger than our solar system<\/a>.<\/p>\n However, for those cold clouds to survive in the superhot environment where they were discovered \u2014 well within the Fermi bubbles, about 13,000 light-years above the galaxy’s center \u2014 they must have been significantly larger when they were first swept up into the thrall of the bubbles, Bordoloi said.<\/p>\n![\"An](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/08\/YBDpxywHMd2dnuyRmfDhFW.jpg\")
<\/p>\n