Astronomy

Historian Craig Fehrman unpacks the science, politics and human stories behind one of America’s most famous expeditions

The European Space Agency's two-satellite HydroGNSS Scout mission has completed commissioning and is now in full scientific operations.

Following extensive testing and validation of the satellites, instruments and ground segment, HydroGNSS data are now freely available to users worldwide, opening new opportunities to advance our understanding of water availability and the impacts of climate change on Earth's water cycle.

Once the bright Moon is out of the evening sky by Monday or so, use Altair high in the southeast to find little Delphinus and Sagitta roughly a fist at arm's length from it.

The post This Week's Sky at a Glance, July 31 – August 9 appeared first on Sky & Telescope.

Most of us are familiar with Betelgeuse (also known as alpha Orionis), the bright shoulder star in the constellation Orion. It's a red supergiant star that lies somewhere between 400 and 550 light-years away from us and is quite bright. Betelgeuse contains about 14 times the mass of the Sun and is a fairly young star compared to ours. It appears to be no more than 10 million years old, which means that it evolved rapidly from a protostar to the red giant we see today. That lifecycle means Betelgeuse will explode as a supernova sometime in the relatively near future — say within the next 100,000 years.

Image: This colourful radar image captured by the Copernicus Sentinel-1 mission features New Orleans and the delta of the Mississippi River, one the largest rivers in North America.

The planet Mercury is the first planet from the Sun but also one shrouded in mystery. This is primarily due to the limited number of spacecrafts that have visited it, but this limited data has provided scientists with new and exciting characteristics previously thought impossible. One fascinating aspect is its magnetic field, which was first discovered in March 1974, which both surprised and puzzled scientists due to the planet’s small size, which is measured at about half the size of the continental United States from coast to coast.

Galaxies in the infancy of the Universe are the building blocks of more modern galaxies. They began as small "shreds" of material that coalesced over time to form larger ones. That's why astronomers use observatories such as the James Webb Space Telescope (JWST) to study the young Universe. The light from those early objects appears in the infrared part of the spectrum, which JWST is tuned to see.

New analysis of observations taken in 2024 confirm a stellar companion for Betelgeuse in the constellation Orion.

The post New Images Confirm: Betelgeuse Has a Companion appeared first on Sky & Telescope.

In 185 AD,

David Haskell brings readers through millions of years of botanical history for his latest book, How Flowers Made Our World

Primordial black holes (PBH) remain hypothetical, but that isn't stopping astrophysicists from figuring out how they could interact with other stellar objects. New research shows how PBHs, formed in the early Universe from collapsing pockets of dense subatomic matter instead of from stars, can enter white dwarfs. In some cases, that could've triggered a Type Ia supernova with particular chemical fingerprints, which should be detectable.

On March 10, 2026, the Fermi telescope gamma-ray burst team reported the detection of a long-duration gamma ray burst that occurred when a star exploded inside a dense, highly magnetized cloud of hydrogen gas. That HII region is a bubble of ionized hydrogen created by winds from a massive young star. Astronomers immediately turned as many telescopes as possible to view the burst and its afterglow, including the NSF's Karl Jansky Very Large Array.

Centuries-old DNA that was found in these mummies belongs to an extinct viral lineage of smallpox that was brought across the Atlantic during European colonization of the Americas

Scientists analyzing modern genomes may have found a long-lost branch of the human family tree

The U.S. has been pummeled with heat waves this summer. Here’s how hot overnight temperatures can get in the way of a good night’s rest—in three charts

Before any major telescope commissioning, there are dozens of papers that attempt to define what we can expect from it. We’re starting to see some come through for the Extremely Large Telescope (ELT), which hopefully will get a more imaginative name when the 39m behemoth is officially commissioned in Chile in the 2030s. A new paper from Evann Kurzawa-Ferrandez and his co-authors at NASA’s Jet Propulsion Laboratory, and available in pre-print on arXiv, showcases what kind of biologically relevant gases we can find on some of our nearest exoplanets.

NASA’s James Webb Space Telescope’s Mid-Infrared Instrument (MIRI) reveals the nearby galaxy Centaurus A, exposing the dusty structures and hidden activity that shape this unusual system.

Space agencies around the globe are coordinating missions to visit the asteroid Apophis during a close encounter with Earth in 2029

Astronomers have long thought supermassive black holes can escape their home galaxies — now they've found one roaming its host's galactic outskirts.

The post Wandering Supermassive Black Hole Found at the Edge of its Galaxy appeared first on Sky & Telescope.

NASA has selected a concept study, led by physicist Paul Stankus, exploring whether a pair of spacecraft flying in tight formation could one day produce an actual image of an Earth like exoplanet's surface, oceans, continents and all. It's an early stage idea, backed by NASA's Innovative Advanced Concepts program, but if it ever came together, it would represent an extraordinary leap beyond simply detecting a distant world to genuinely seeing its face.