Impact! 65 Million Years Ago
12.10.1997

What killed the dinosaurs? Their sudden disappearance 65 million years ago, along with about 70 percent of all species then living on Earth, is known as the K-T event (Cretaceous-Tertiary Mass Extinction event). Geologists and paleontologists often entertain the idea of a large asteroid

A Double Ringed Basin on Mercury
7.10.2009

What created the internal second ring of this double ringed basin on Mercury? No one is sure. The unusual feature spans 160 kilometers and was imaged during the robotic MESSENGER spacecraft's swing past our Solar System's innermost planet last week.

Looking Sideways from the Parker Solar Probe
9.12.2019

Everybody sees the Sun. Nobody's been there. Starting in 2018 though, NASA launched the robotic Parker Solar Probe (PSP) to investigate regions near to the Sun for the first time. The PSP's looping orbit brings it yet closer to the Sun each time around -- every few months.

Haunting the Cepheus Flare
28.10.2016

Spooky shapes seem to haunt this jeweled expanse, drifting through the night in the royal constellation Cepheus. Of course, the shapes are cosmic dust clouds faintly visible in dimly reflected starlight. Far from your...

Asteroid or Potato
1.04.2020

Is this asteroid Arrokoth or a potato? Perhaps, after all the data was beamed back to Earth from NASA's robotic New Horizons spacecraft, the featured high resolution image of asteroid Arrokoth was constructed. Perhaps, alternatively, the featured image is of a potato. Let's consider some facts.

The 47 Ursae Majoris System
17.08.2001

Watching and waiting, astronomers have uncovered the presence of more than 70 planets orbiting stars other than the Sun. So far almost all these extrasolar planets have crazy elongated orbits, lie uncomfortably close to their parent stars, or are found in bizarre, inhospitable systems.

APOD: 2026 May 12 Б The Conjunction of Comet R3 PanSTARRS and the Orion Nebula
12.05.2026

TodayБs composite image features something old, something new, something borrowed, and something blue! Comet R3 PanSTARRS, streaking across the right of the image, likely originated from the Oort Cloud, meaning it is an old Solar System relic from billions of years ago.

Impact! 65 Million Years Ago
4.06.1996

What killed the dinosaurs? Their sudden disappearence 65 million years ago, along with about 70 percent of all species then living on Earth, is known as the K-T event (Cretaceous-Tertiary Mass Extinction event). Geologists and paleontologists often entertain the idea of a large asteroid or comet impacting the Earth as the culprit.

Tonight: A Blue Moon
31.07.2004

How often does a full moon occur twice in a single month? Exactly once in a Blue Moon. In fact, the modern usage of the term "Blue Moon" refers to the second Full Moon in a single month. Tonight's Blue Moon will be the first since November 2001.

A Lunar Eclipse on Solstice Day
20.12.2010

Sometime after sunset tonight, the Moon will go dark. This total lunar eclipse, where the entire Moon is engulfed in the shadow of the Earth, will be visible from all of North America, while the partial phase of this eclipse will be visible throughout much of the rest of the world.