Sunrise over the Parthenon
21.06.2009

Today, the sun will stay in the sky longer than any other day of the year, as seen from the northern hemisphere of Earth. Named the Summer Solstice, today's maximum daylight is indicative of the high amount of sunlight this time of year that is primarily responsible for the heat of the summer season.

Circling the Sun
12.01.2024

Earth's orbit around the Sun is not a circle, it's an ellipse. The point along its elliptical orbit where our fair planet is closest to the Sun is called perihelion. This year...

September Sunrise Shadows
23.09.2022

The defining astronomical moment for this September's equinox was on Friday, September 23, 2022 at 01:03 UTC, when the Sun crossed the celestial equator moving south in its yearly journey through planet Earth's sky.

A Journey Through the Night Sky
20.05.2011

Majestic nebulae and stars of our Milky Way Galaxy stretch across this panoramic image of the entire night sky. At full resolution, the 5 gigapixel mosaic was stitched together from over 37,000 images...

Dry Ice Pits on Mars
26.09.2011

Part of Mars is defrosting. Around the South Pole of Mars, toward the end of every Martian summer, the warm weather causes a section of the vast carbon-dioxide ice cap to evaporate. Pits begin to appear and expand where the carbon dioxide dry ice sublimates directly into gas.

Mars near Opposition
11.04.2014

Tonight Mars is between opposition (April 8) and closest approach (April 14) looping through the constellation Virgo opposite the Sun in the night sky. That makes it prime season for telescopic views of the the Red Planet, like this one from April 3rd.

A Spectre in the Eastern Veil
30.10.2013

Frightening forms and scary faces are a mark of the Halloween season. They also haunt this cosmic close-up of the eastern Veil Nebula. The Veil Nebula itself is a large supernova remnant, the expanding debris cloud from the death explosion of a massive star.

APOD: 2024 March 19 Б A Picturesque Equinox Sunset
18.03.2024

What's that at the end of the road? The Sun. Many towns have roads that run east-west, and on two days each year, the Sun rises and sets right down the middle. Today, in some parts of the world (tomorrow in others), is one of those days: an equinox.

A Spectre in the Eastern Veil
29.10.2014

Frightening forms and scary faces are a mark of the Halloween season. They also haunt this cosmic close-up of the eastern Veil Nebula. The Veil Nebula itself is a large supernova remnant, the expanding debris cloud from the death explosion of a massive star.

Perihelion to Aphelion
8.01.2020

Perihelion for 2020, the point in Earth's elliptical orbit when it is closest to the Sun, occurred on January 5th. The distance from the Sun doesn't determine the seasons, though. Those...