The Sun Also Rises
17.11.1995

Sunrise seen from low Earth orbit by the shuttle astronauts can be very dramatic indeed (and the authors apologize to Hemingway for using his title!). In this breathtaking view, the Sun is just visible...

APOD: 2023 August 1 Б Monster Solar Prominence
1.08.2023

The monsters that live on the Sun are not like us. They are larger than the Earth and made of gas hotter than in any teapot. They have no eyes, but at times, many tentacles. They float. Usually, they slowly change shape and just fade back onto the Sun over about a month.

Sun and Winter Solstice 1996
21.12.1996

Today is the Winter Solstice for 1996. After steadily sinking in Northern Hemisphere skies, the Sun is now at its lowest declination - marking the first day of Northern Winter (but Southern Summer!). The Earth...

APOD: 2024 May 15 Б AR 3664 at the Suns Edge
15.05.2024

What did the monster active region that created the recent auroras look like when at the Sun's edge? There, AR 3664 better showed its 3D structure. Pictured, a large multi-pronged solar prominence...

The Galaxy, the Jet, and a Famous Black Hole
9.05.2024

Bright elliptical galaxy Messier 87 (M87) is home to the supermassive black hole captured in 2017 by planet Earth's Event Horizon Telescope in the first ever image of a black hole. Giant...

APOD: 2024 May 7 Б Black Hole Accreting with Jet
7.05.2024

What happens when a black hole devours a star? Many details remain unknown, but observations are providing new clues. In 2014, a powerful explosion was recorded by the ground-based robotic telescopes of the All Sky Automated Survey for SuperNovae (Project ASAS-SN), with followed-up observations by instruments including NASA's Earth-orbiting Swift satellite.

APOD: 2023 September 19 Б HH 211: Jets from a Forming Star
19.09.2023

Do stars always create jets as they form? No one is sure. As a gas cloud gravitationally contracts, it forms a disk that can spin too fast to continue contracting into a protostar. Theorists hypothesize that this spin can be reduced by expelling jets.

A Jet from Galaxy M87
6.07.2000

What's causing a huge jet to emanate from the center of galaxy M87? Although the unusual jet was first noticed early in the twentieth century, the exact cause is still debated. The above recently released picture taken by the Hubble Space Telescope shows clear details, however.

Flying Saucer Crash Lands in Utah Desert
13.11.2022

A flying saucer from outer space crash-landed in the Utah desert after being tracked by radar and chased by helicopters. The year was 2004, and no space aliens were involved. The saucer, pictured here...

The Local Bubble and the Galactic Neighborhood
17.02.2002

What surrounds the Sun in this neck of the Milky Way Galaxy? Our current best guess is depicted in the above map of the surrounding 1500 light years constructed from various observations and deductions.