Sharpest Ultima Thule
28.02.2019

On January 1, New Horizons swooped to within 3,500 kilometers of the Kuiper Belt world known as Ultima Thule. That's about 3 times closer than its July 2015 closest approach to Pluto.

Particle Sizes in Saturns Rings
25.05.2005

What size particles compose Saturn's rings? To help find out, the robot Cassini spacecraft now orbiting Saturn broadcast radio waves of three different wavelengths right through the rings to Earth earlier this month.

An Unusual Mountain on Asteroid Ceres
30.06.2015

What created this large mountain on asteroid Ceres? No one is yet sure. As if in anticipation of today being Asteroid Day on Earth, the robotic spacecraft Dawn in orbit around Ceres took the best yet image of an unusually tall mountain on the Asteroid Belt's largest asteroid.

Saturns Northern Hexagon
5.07.2020

Why would clouds form a hexagon on Saturn? Nobody is sure. Originally discovered during the Voyager flybys of Saturn in the 1980s, nobody has ever seen anything like it anywhere else in the Solar System.

Comet Lovejoy: Sungrazing Survivor
17.12.2011

Like most other sungrazing comets, Comet Lovejoy (C/2011 W3) was not expected to survive its close encounter with the Sun. But it did. This image from a coronograph onboard the sun-staring SOHO spacecraft identifies the still inbound remnants of the tail, with the brilliant head or coma emerging from the solar glare on December 16.

APOD: 2025 November 16 Б Crossing Saturns Ring Plane
16.11.2025

If this is Saturn, where are the rings? When Saturn's "appendages" disappeared in 1612, Galileo did not understand why. Later that century, it became understood that Saturn's unusual protrusions were rings and that when the Earth crosses the ring plane, the edge-on rings will appear to disappear.

Landing At The Martian South Pole
1.12.1999

The latest invader from Earth, the Mars Polar Lander (MPL) spacecraft, is scheduled to touch down on the Red Planet's surface on Friday, December 3rd. If all goes well the robotic explorer will...

Swirling Clouds Over the South Pole of Venus
1.05.2007

What's happening over the South Pole of Venus? To find out, scientists sent the robot Venus Express spacecraft now orbiting Venus directly over the lower spin axis of Earth's overheated twin. Venus Express confirmed there a spectacular massive swirling storm system with similarities to the vortex recently imaged over Saturn's South Pole.

Saturn: Bright Tethys and Ancient Rings
16.09.2012

How old are Saturn's rings? No one is quite sure. One possibility is that the rings formed relatively recently in our Solar System's history, perhaps only about 100 million years ago when a moon-sized object broke up near Saturn.

Aurora around Saturns North Pole
3.09.2018

Are Saturn's auroras like Earth's? To help answer this question, the Hubble Space Telescope and the Cassini spacecraft monitored Saturn's North Pole simultaneously during Cassini's final orbits around the gas giant in September 2017. During this time, Saturn's tilt caused its North Pole to be clearly visible from Earth.