XMM Launched
21.12.1999

X-ray astronomy entered a golden age earlier this month with the successful launch of the X-ray Multi-Mirror (XMM) satellite. XMM's three huge telescope barrels each hold 58 concentric cylindrical mirrors, together totaling a surface area rivaling a tennis court.

A Desert Eclipse
13.01.2020

A good place to see a ring-of-fire eclipse, it seemed, would be from a desert. In a desert, there should be relatively few obscuring clouds and trees. Therefore late last December a group...

Boston Moonrise
24.03.2011

Last week's Full Moon was hard to miss. Rising on March 19, its exact full phase occurred within an hour of perigee, the closest point in the Moon's orbit to Earth.

NGC 5189: An Unusually Complex Planetary Nebula
19.12.2012

Why is this nebula so complex? When a star like our Sun is dying, it will cast off its outer layers, usually into a simple overall shape. Sometimes this shape is a sphere, sometimes a double lobe, and sometimes a ring or a helix.

Bright Planetary Nebula NGC 7027 from Hubble
9.01.2018

It is one of the brightest planetary nebulae on the sky -- what should it be named? First discovered in 1878, nebula NGC 7027 can be seen toward the constellation of the Swan (Cygnus) with a standard backyard telescope.

A Total Lunar Eclipse Video
20.01.2019

Tonight a bright full Moon will fade to red. Tonight's moon will be particularly bright because it is reaching its fully lit phase when it is relatively close to the Earth in its elliptical orbit.

Live: Watching for Venus to Cross the Sun
5.06.2012

Today Venus moves in front of the Sun. One way to follow this rare event is to actively reload the above live image of the Sun during the right time interval and look for an unusual circular dark dot. The smaller sprawling dark areas are sunspots. The circular dot is the planet Venus.

Saturn at Night
20.09.2019

Still bright in planet Earth's night skies, good telescopic views of Saturn and its beautiful rings often make it a star at star parties. But this stunning view of Saturn's rings and night side just isn't possible from telescopes closer to the Sun than the outer planet.

Saturn at Night
11.09.2021

Still bright in planet Earth's night skies, good telescopic views of Saturn and its beautiful rings often make it a star at star parties. But this stunning view of Saturn's rings and night side just isn't possible from telescopes closer to the Sun than the outer planet.

Comet Lovejoy and the ISS
31.12.2011

On December 24, Comet Lovejoy rose in dawn's twilight, arcing above the eastern horizon, its tails swept back by the solar wind and sunlight. Seen on the left is the comet's early morning appearance alongside the southern Milky Way from the town of Intendente Alvear, La Pampa province, Argentina.