Solar Flare from a Sharper Sun
21.11.2014

Solar active region AR2192 was the largest recorded sunspot group of the last 24 years. Before rotating off the Earth-facing side of the Sun at the end of October, it produced a whopping six energetic X-class flares.

The Sun in X rays from NuSTAR
28.12.2014

Why are the regions above sunspots so hot? Sunspots themselves are a bit cooler than the surrounding solar surface because the magnetic fields that create them reduce convective heating. It is therefore unusual that regions overhead -- even much higher up in the Sun's corona -- can be hundreds of times hotter.

Martian Moon Phobos Crosses the Sun
9.04.2019

What's that passing in front of the Sun? It looks like a moon, but it can't be Earth's Moon, because it isn't round. It's the Martian moon Phobos. The featured video was taken from the surface of Mars late last month by the Curiosity rover.

The Flash Spectrum of the Sun
6.09.2017

In clear Madras, Oregon skies, this colorful eclipse composite captured the elusive chromospheric or flash spectrum of the Sun. Only three exposures, made on August 21 with telephoto lens and diffraction grating, are aligned in the frame.

Coronal Rain on the Sun
26.05.2018

Does it rain on the Sun? Yes, although what falls is not water but extremely hot plasma. An example occurred in mid-July 2012 after an eruption on the Sun that produced both a Coronal Mass Ejection and a moderate solar flare. What was more unusual, however, was what happened next.

APOD: 2020 August 2 Б Two Worlds One Sun
1.08.2020

How different does sunset appear from Mars than from Earth? For comparison, two images of our common star were taken at sunset, one from Earth and one from Mars. These images were scaled to have same angular width and featured here side-by-side.

APOD: 2025 June 15 Б Two Worlds One Sun
14.06.2025

How different does sunset appear from Mars than from Earth? For comparison, two images of our common star were taken at sunset, one from Earth and one from Mars. These images were scaled to have the same angular width and are featured here side-by-side.

Comet Bradfield Passes the Sun
19.04.2004

Right now, Comet Bradfield is passing the Sun. The above image, the latest taken in the direction of the Sun by the SOHO LASCO instrument, shows the comet and its dust tail as the elongated white streak. The Sun would normally be seen in the very center but has been blocked from view.

A Filament Leaps from the Sun
7.11.2021

Why, sometimes, does part of the Sun's atmosphere leap into space? The reason lies in changing magnetic fields that thread through the Sun's surface. Regions of strong surface magnetism, known as active regions, are usually marked by dark sunspots.

APOD: 2020 August 18 Б TYC 8998 760 1: Multiple Planets around a Sun Like Star
17.08.2020

Do other stars have planets like our Sun? Previous evidence shows that they do, coming mostly from slight shifts in the star's light created by the orbiting planets. Recently, however, and for the first time, a pair of planets has been directly imaged around a Sun-like star.