A Hole in Mars Close Up
28.09.2007

In a close-up from the HiRISE instrument onboard the Mars Reconnaissance Orbiter, this mysterious dark pit, about 150 meters across, lies on the north slope of ancient martian volcano Arsia Mons. Lacking raised rims...

Wisps Surrounding the Horsehead Nebula
6.04.2008

The famous Horsehead Nebula in Orion is not alone. A deep exposure shows that the dark familiar shaped indentation, visible just below center, is part of a vast complex of absorbing dust and glowing gas.

The Missing Craters of Asteroid Itokawa
9.02.2014

Where are the craters on asteroid Itokawa? Missing -- unexpectedly. The Japanese robot probe Hayabusa approached the Earth-crossing asteroid in 2005 and returned pictures showing a surface unlike any other Solar System body yet photographed -- a surface possibly devoid of craters.

APOD: 2025 February 9 Б Milky Way over the Australian Pinnacles
8.02.2025

What strange world is this? Earth. In the foreground of the featured image are the Pinnacles, unusual rock spires in Nambung National Park in Western Australia. Made of ancient sea shells (limestone), how these human-sized picturesque spires formed remains unknown.

Sextans A: A Seemingly Square Galaxy
2.11.1998

What's bothering local galaxy Sextans A? A small dwarf irregular galaxy spanning 5 thousand light years across, Sextans A is located only 5 million light-years away. Named for its home constellation of Sextans, the "diamond in the rough" structure relates to an ancient unknown event.

3-D Mars North Pole
15.12.1998

This dramatic premier three-dimensional visualization of Mars' north pole is based on elevation measurements made by an orbiting laser. During the Spring and Summer of 1998 the Mars Orbiter Laser Altimeter (MOLA) flashed laser pulses toward the Martian surface from the Global Surveyor spacecraft and recorded the time it took to detect the reflection.

Metal on the Plains of Mars
31.07.2011

What has the Opportunity rover found on Mars? While traversing a vast empty plain in 2005 in Meridiani Planum, one of Earth's rolling robots on Mars found a surprise when visiting the location of its own metallic heat shield discarded last year during descent.

Perseverance in Jezero Crater s Delta
16.09.2022

The Perseverance rover's Mastcam-Z captured images to create this mosaic on August 4, 2022. The car-sized robot was continuing its exploration of the fan-shaped delta of a river that, billions of years ago, flowed into Jezero Crater on Mars.

Strange Orange Soil on the Moon
23.05.2001

How did orange soil appear on the Moon? This mystery began when astronaut Harrison Schmidt noticed the off-color patch near Apollo 17's Taurus-Littrow landing site in 1972. Schmidt and fellow astronaut Eugene Cernan scooped up some of the unusual orange soil for detailed inspection back on Earth.

Comet Encke s Tail Ripped off
3.10.2007

Swinging inside the orbit of Mercury, on April 20th periodic comet Encke encountered a blast from the Sun in the form of a Coronal Mass Ejection (CME). When CMEs, enormous clouds of energetic particles ejected from the Sun, slam into Earth's magnetosphere, they often trigger auroral displays.