Time Lapse Auroras Over Norway
28.03.2011

Sometimes, after your eyes adapt to the dark, a spectacular sky appears. Such was the case earlier this month when one of the largest auroral displays in recent years appeared over northern locations like the border between Norway and Russia.

Animation: Perseid Meteor Shower
8.08.2018

Where do Perseid meteors come from? Mostly small bits of stony grit, Perseid meteoroids were once expelled from Comet Swift-Tuttle and continue to follow this comet's orbit as they slowly disperse. The featured animation depicts the entire meteoroid stream as it orbits our Sun.

APOD: 2023 September 18 Б The Red Sprite and the Tree
18.09.2023

The sprite and tree could hardly be more different. To start, the red sprite is an unusual form of lightning, while the tree is a common plant. The sprite is far away -- high in Earth's atmosphere, while the tree is nearby -- only about a football field away.

A Meteor Wind over Tunisia
16.08.2022

Does the Earth ever pass through a wind of meteors? Yes, and they are frequently visible as meteor showers. Almost all meteors are sand-sized debris that escaped from a Sun-orbiting comet or asteroid, debris that continues in an elongated orbit around the Sun.

APOD: 2023 December 5 Б Energetic Particle Strikes the Earth
5.12.2023

It was one of the most energetic particles ever known to strike the Earth -- but where did it come from? Dubbed Amaterasu after the Shinto sun goddess, this particle, as do all cosmic rays...

Meteors, Comet, and Big Dipper over La Palma
23.04.2019

Meteor showers are caused by streams of solid particles, dust size and larger, moving as a group through space. In most cases, the orbits of these meteor streams can be identified with dust expelled from a comet.

Video of a Green Flash
10.11.2021

Many think it is just a myth. Others think it is true but its cause isn't known. Adventurers pride themselves on having seen it. It's a green flash from the Sun. The truth is the green flash does exist and its cause is well understood.

Blue Marble Earth
6.02.2022

Welcome to planet Earth, the third planet from a star named the Sun. The Earth is shaped like a sphere and composed mostly of rock. Over 70 percent of the Earth's surface is water. The planet has a relatively thin atmosphere composed mostly of nitrogen and oxygen.

APOD: 2024 May 22 Б Green Aurora over Sweden
22.05.2024

It was bright and green and stretched across the sky. This striking aurora display was captured in 2016 just outside of цstersund, Sweden. Six photographic fields were merged to create the featured panorama spanning almost 180 degrees. Particularly striking aspects of this aurora include its sweeping arc-like shape and its stark definition.

The First Lunar Observatory
11.11.2000

The first, and so far only, lunar astronomical observatory was deployed by the Apollo 16 crew in 1972. The Far Ultraviolet Camera / Spectrograph used a 3-inch diameter Schmidt telescope to photograph the Earth, nebulae, star clusters, and the Large Magellanic Cloud.