Milky Way and Aurora over Antarctica

2023-07-02 LI Hang

It was one of the better skies of this long night. In parts of Antarctica, not only is it winter, but the Sun can spend weeks below the horizon. At China's Zhongshan Station, people sometimes venture out into the cold to photograph a ...

Three Galaxies in Draco

2023-07-01 David Vernet , Jean-François Bax , Serge Brunier

This tantalizing trio of galaxies sometimes called the Draco Group, is located in the northern constellation of (you guessed it) Draco, the Dragon. From left to right are face-on spiral NGC 5985, elliptical galaxy NGC 5982, and edge-on spiral NGC ...

Orbits of Potentially Hazardous...

2023-06-30

Are asteroids dangerous? Some are, but the likelihood of a dangerous asteroid striking the Earth during any given year is low. Because some past mass extinction events have been linked to asteroid impacts, however, humanity has made it a priority ...

A Message from the Gravitational...

2023-06-29

Monitoring 68 pulsars with very large radio telescopes, the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has uncovered evidence for the gravitational wave (GW) background by carefully measuring slight shifts in the ...

Messier 24: Sagittarius Star Cloud

2023-06-28 Emmanuel Astronomono

Unlike most entries in Charles Messier's famous catalog of deep sky objects, M24 is not a bright galaxy, star cluster, or nebula. It's a gap in nearby, obscuring interstellar dust clouds that allows a view of the distant stars in the ...

MAVEN's Ultraviolet Mars

2023-06-27

These two global views of Mars were captured at ultraviolet wavelengths, beyond the spectrum visible to human eyes. Recorded by the MAVEN spacecraft's Imaging Ultraviolet Spectrograph instrument in July 2022 (left) and January 2023, three ...

The Belt of Venus over Mount Everest

2023-06-26 Soumyadeep Mukherjee

You've surely seen it, but you might not have noticed it. During a cloudless twilight, just before sunrise or after sunset, part of the atmosphere above the horizon appears slightly dark and off-color. Called the Belt of Venus, this ...

Lightning on Jupiter

2023-06-25

Does lightning occur only on Earth? No. Spacecraft in our Solar System have detected lightning on other planets, including Mars, Jupiter and Saturn, and lightning is likely on Venus, Uranus, and Neptune. Lightning is a sudden rush of ...

3D Ingenuity

2023-06-24

The multicolor, stereo imaging Mastcam-Z on the Perseverance rover zoomed in to capture this 3D close-up (get out your red/blue glasses) of the Mars Ingenuity helicopter on mission sol 45. That's Earth-date 2021 April 5. Casting a shadow on ...

Giant Galaxies in Pavo

2023-06-23 Mike Selby

Over 500,000 light years across, NGC 6872 (top right) is a truly enormous barred spiral galaxy, at least 5 times the size of our own very large Milky Way. The appearance of this giant galaxy's distorted and stretched out spiral arms suggests ...