141–160 of 5,892 results
Waning Moon under Saturn at dawn, April 14-16, 2023

Celestial News & Events

This Week's Sky at a Glance, April 14 – 23

Venus shines with Aldebaran and the Pleiades in late twilight. After sunset on the 20th, try to spot your record-breaking thinnest young Moon. And Leo walks west with a mouse-galaxy dangling from his chin.

Black field spotted with galaxies

Cosmology

What the Discovery of Massive Early Galaxies Could Mean for Cosmology

JWST's detection of early galaxies that are far more massive than astronomers had expected could mean we need to rewrite our understanding of the cosmos.

International Dark Sky Week 2023

Save Dark Skies

"Discover the Night" During International Dark Sky Week, April 15–22

Protect the night sky — join the International Dark-Sky Association for activities during International Dark-Sky Week.

Radio waves from fast radio burst penetrate intergalactic plasma on their way to Earth in the Milky Way

Stellar Science

Mystery Bursts Give Astronomers a View into Galaxy Halos

Flashes of radio waves — whose exact sources are still a bit of a mystery — are helping astronomers learn about the hot gas that surrounds the Milky Way.

Giant planets around a small, red-colored star

Exoplanets

Giant Planets Around Small Stars

Leading theories say giant planets shouldn’t be able to form around very low-mass stars. But a new study finds that, nevertheless, they do.

Venus near the Pleiades, Hyades, and Aldebaran, April 11, 2023

This Week's Sky At a Glance

This Week's Sky at a Glance, April 7 – 16

Venus in the western twilight guides the way down to Mercury. The Pleiades pass by Venus far in its background. And can you find the head of Hydra?

Total Solar Eclipse Madras, Oregon

Celestial News & Events

The "Great American" Solar Eclipse Is Just a Year Away

A long totality passing through Mexico, the U.S., and Canada beckons — and planning ahead will be crucial.

Quasi-Moon orbit

Solar System

Does Earth Have a New Quasi-Moon?

Astronomers have discovered an asteroid that orbits the Sun with Earth, earning it the moniker "quasi-moon."

The planet Uranus on a black background. The planet appears light blue with a large, white patch on the right side. The image is labelled to indicate the locations of the planet’s clouds, polar cap, and zeta ring

Solar System

James Webb Space Telescope Captures Another Ringed Planet

Webb has returned an image of ringed Uranus, currently experiencing the dog days of northern hemisphere summer.

Elnath's position in Taurus constellation

Night Sky Sights

Meet Elnath in the Horn of the Bull

Elnath, the bright, blue-white star that marks one of the horns of Taurus, is a peculiar star in its own right.

Astronomy in Space with David Dickinson

Artemis II Crew Selection, Mission Update

NASA has announced the names for the Artemis 2 crew headed to the Moon in 2024. Meanwhile, the Artemis program as a whole is taking shape.

Mercury & Venus April 2023

Sky Tour Astronomy Podcast

April: Mercury & Venus at Their Best

This month’s episode offers an easy-to-follow guide to finding the solar system’s two innermost planets after sunset. And then it takes you on a guided tour of the rest of the key stars and planets that you’ll see on April evenings — a fun and informative way to introduce yourself to the nighttime sky!

An X-ray image of GRB 221009A

Stellar Science

Focusing on the Brightest Gamma-ray Burst of All Time

Gamma-ray bursts are the most luminous explosions in the universe, and we’ve learned much about these superlative outbursts since their discovery in 1967.

Mercury below Venus in the western twilight, April 7, 2023

Celestial News & Events

This Week's Sky at a Glance, March 31 – April 8

Mercury emerges this week far below Venus at dusk, while Venus makes its way toward the Pleiades. Orion turns his belt horizontal for the warming weather.

Artist's concept of a first-generation star tearing itself apart

Cosmology

The First Stars Weren’t Born Alone

New evidence suggests the first stars to shine in the universe formed in groups.

Lunarisms locator

Celestial News & Events

Pleasures of Lunar Pareidolia

Do you still see animal shapes in clouds? If so, you'll enjoy doing the same with the Moon, home to the Moon Maiden, a giant pair of scissors, and other fantastic specters of light and shadow.

Visualization of airless TRAPPIST-1b and its red dwarf star host

Exoplanets

Exoplanet TRAPPIST-1b Has No Atmosphere

The TRAPPIST exoplanets offer the James Webb Space Telescope some of the best opportunities to observe rocky worlds. But Webb images show the innermost planet b has no atmosphere.

Astronomy and Society

Satellites and Space Debris Are Polluting Our Night Skies

Astronomers are sounding the alarm about low-Earth orbit satellites and space debris as significant contributors to light pollution that will affect even the remotest earthbound stargazer.

Moon passing Mars in Gemini, March 27-28, 2023

Celestial News & Events

This Week's Sky at a Glance, March 24 – April 2

The Winter Hexagon fills the west after dark. The waxing Moon steps east across the evening sky from Venus past the Pleiades, then past Mars.

People, Places, and Events

The Northeast Astronomy Forum Is Back in 2023

The Northeast Astronomy Forum in Suffern, NY, welcomes visitors from across the world on April 15–16, and we'll be there — will you?