APOD: 2023 October 3 Б MyCn 18: The Engraved Hourglass Planetary Nebula
3.10.2023

Do you see the hourglass shape -- or does it see you? If you can picture it, the rings of MyCn 18 trace the outline of an hourglass -- although one with an unusual eye in its center. Either way, the sands of time are running out for the central star of this hourglass-shaped planetary nebula.

A Meteor Shower Fireball Movie
12.08.2005

Go outside tonight and see a celestial light show -- the later the better. Tonight is the peak of the month-long Perseid Meteor Shower. Although visible every year at this time, the Perseids are expected to appear particularly active this year due to the relative absence of glare from the Moon during the peak.

A Perseid Meteor
12.08.2000

This weekend, the annual Perseid Meteor Shower reaches its maximum. Grains of cosmic sand and gravel shed from Comet Swift-Tuttle will streak across the sky as they vaporize during entry into Earth's atmosphere. The Perseids result from the yearly

Leonids Over Joshua Tree National Park
5.11.2002

This year's Leonid Meteor Shower is predicted to have two peaks, like last year's. The first peak should come at about 04:00 hours Universal Time (UT) on November 19 and be primarily visible from Western Europe before sunrise.

APOD: 2023 November 7 Б A Martian Dust Devil Spins By
7.11.2023

It moved across the surface of Mars -- what was it? A dust devil. Such spinning columns of rising air are heated by the warm surface and are also common in warm and dry areas on planet Earth.

Perseids Around the Milky Way
17.08.2020

Why would meteor trails appear curved? The arcing effect arises only because the image artificially compresses (nearly) the whole sky into a rectangle. The meteors are from the Perseid Meteor Shower that peaked last week.

APOD: 2025 November 30 Б The Surface of Titan from Huygens
30.11.2025

If you could stand on Titan -- what would you see? The featured color viewa from Titan gazes across an unfamiliar and distant landscape on Saturn's largest moon. The scene was recorded by ESA's Huygens probe in 2005 after a 2.5-hour descent through a thick atmosphere of nitrogen laced with methane.

Rectangular Ridges on Mars
1.10.2002

What could cause rectangular ridges on Mars? As data flows in from the two spacecraft currently orbiting Mars, surface structures are seen that are not immediately understood. These structures pose puzzles that planetary geologists are eager to solve, as they might provide clues to past processes that have shaped Mars over billions of years.

Meteors Over Quebec
16.08.2010

Meteors streaked through the sky above many of Earth's cities last week, but nobody was hurt, and no damage has been reported. The assault from space appeared to originate from someplace in the constellation of Perseus, and included millions of small projectiles hurtling toward Earth at over 200,000 kilometers per hour.

The Seasons of Saturn
5.04.2003

Since Saturn's axis is tilted as it orbits the Sun, Saturn has seasons, like those of planet Earth ... but Saturn's seasons last for over seven years. So what season is it on Saturn now? Orbiting the equator, the tilt of the rings of Saturn provides quite a graphic seasonal display.