New ALMA observations reveal a never-before-seen disk of cool, interstellar gas wrapped around the supermassive black hole at the center of the Milky Way. This nebulous disk gives astronomers new insights into the workings of accretion: the siphoning of material onto the surface of a black hole. The results are published in the journal Nature. Through…

Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) surveyed dozens of young stars — some Sun-like and others approximately double that size — and discovered that the larger variety have surprisingly rich reservoirs of carbon monoxide gas in their debris disks. In contrast, the lower-mass, Sun-like stars have debris disks that are virtually gas-free. This…

A violent outburst by the young star V883 Orionis has given astronomers their first view of a water “snowline” in a protoplanetary disk — the transition point around the star where the temperature and pressure are low enough for water ice to form. An abrupt increase in the brightness of the star “flash heated” the…

Subtle distortions hidden in ALMA’s stunning image of the gravitational lens SDP.81 are telltale signs that a dwarf dark galaxy is lurking in the halo of a much larger galaxy nearly 4 billion light-years away. This discovery paves the way for ALMA to find many more such objects and could help astronomers address important questions…

New results from NANOGrav – the North American Nanohertz Observatory for Gravitational Waves – establish astrophysically significant limits in the search for low-frequency gravitational waves. This result provides insight into how often galaxies merge, and how those merging galaxies evolve over time. To obtain this result, scientists required an exquisitely precise, nine-year pulsar-monitoring campaign conducted…

Astronomers using an orbiting radio telescope in conjunction with four ground-based radio telescopes have achieved the highest resolution, or ability to discern fine detail, of any astronomical observation ever made. Their achievement produced a pair of scientific surprises that promise to advance the understanding of quasars, supermassive black holes at the cores of galaxies. The…

Using ALMA, astronomers have taken a new, detailed look at the very early stages of planet formation around a binary star. Embedded in the outer reaches of a double star’s protoplanetary disk, the researchers discovered a striking crescent-shape region of dust that is conspicuously devoid of gas. This result, presented at the AAAS meeting in…