All posts tagged: gas cloud

Sun-like star’s nine-month eclipse exposes a violent planetary past

Sun-like star’s nine-month eclipse exposes a violent planetary past

A Sun-type star situated nearly 3,000 light-years from Earth has provided astronomers with a unique opportunity to observe an unusual after-effect of a planetary system’s evolution. When this star, designated J0705+0612, underwent a complete dimming event in September 2024, it remained dim for around nine months. This dimming was an incredible 40 times the usual brightness of this star, something which immediately concerned Nadia Zakamska, an astrophysicist at Johns Hopkins University. “Stars like the Sun don’t just spontaneously cease shining,” said Zakamska. “The likelihood of such a significant dimming event occurring naturally is very small.” Working together with a multi-institutional group, Zakamska quickly arranged for access to several telescopes located in Chile, including the Gemini South telescope from the International Gemini Observatory supported by NSF NOIRLab. This was in addition to data obtained from the Apache Point Observatory and the Magellan Telescopes. Their findings were published in The Astronomical Journal. From a dizzying height, the full scale and remoteness of the Gemini South telescope, one half of the International Gemini Observatory, operated by NSF NOIRLab, …

Cloud-9: Astronomers spot a gas-rich cloud dominated by dark matter that contains no stars

Cloud-9: Astronomers spot a gas-rich cloud dominated by dark matter that contains no stars

Astronomers using the NASA and European Space Agency’s Hubble Space Telescope have identified what appears to be a long-predicted but never before confirmed cosmic object: a gas-rich cloud dominated by dark matter that contains no stars. The object, known as Cloud-9, sits near the spiral galaxy Messier 94 and offers rare, direct evidence of a “failed galaxy,” a structure that began forming billions of years ago but never completed the process. The research was led by Alejandro Benitez-Llambay of Milano-Bicocca University in Milan, Italy, with major contributions from scientists at the Space Telescope Science Institute in Baltimore. The findings were published in The Astrophysical Journal Letters and combine deep optical observations from Hubble with earlier radio detections from some of the world’s most powerful ground-based telescopes. “This is a tale of a failed galaxy,” Benitez-Llambay said. “In science, we usually learn more from the failures than from the successes. In this case, seeing no stars is what proves the theory right. It tells us that we have found in the local Universe a primordial building …