Highlights of the Summer Sky
5.06.2017

What's up in the sky this summer? The featured graphic gives a few highlights for Earth's northern hemisphere. Viewed as a clock face centered at the bottom, early summer sky events fan out toward the left, while late summer events are projected toward the right.

Planet Earth at Blue Hour
11.10.2019

Nature photographers and other fans of planet Earth always look forward to the blue hour. That's the transition in twilight, just before sunrise or after sunset, when the Sun is below the horizon but land and sky are still suffused with beautiful bluish hues of light.

APOD: 2024 June 9 Б How to Identify that Light in the Sky
9.06.2024

What is that light in the sky? The answer to one of humanity's more common questions may emerge from a few quick observations. For example -- is it moving or blinking?

Messenger Launch
14.08.2004

Streaking into the early morning sky on August 3rd, a Delta II rocket launches NASA's Messenger spacecraft on an interplanetary voyage to Mercury. Scheduled to become the first probe to orbit Mercury, Messenger will begin by looping through the inner Solar System in a series of close flybys of planet Earth and Venus.

Comet McNaught Over Catalonia
15.01.2007

This past weekend Comet McNaught peaked at a brightness that surpassed even Venus. Fascinated sky enthusiasts in the Earth's northern hemisphere were treated to an instantly visible comet head and a faint elongated tail near sunrise and sunset.

Ecliptic New Zealand
10.07.2010

Four bright celestial beacons and a faint triangle of light follow the plane of the ecliptic as it arcs high through this southern hemisphere night skyscape. Seen on a July winter night from Lake...

Massive Black Hole Shreds Passing Star
28.10.2015

What happens when a star gets too close to a black hole? Recent observations from Earth-orbiting observatories of an event dubbed ASASSN-14li, in a distant galactic center, appears to be giving one star's harrowing story.

Sunrise Analemma (with a little extra)
20.09.2012

An analemma is that figure-8 curve that you get when you mark the position of the Sun at the same time each day throughout planet Earth's year. In this case, 17 individual images...

Solar System Portrait
14.02.2013

On another Valentine's Day (February 14, 1990), cruising four billion miles from the Sun, the Voyager 1 spacecraft looked back to make this first ever family portrait of our Solar System. The complete portrait is a 60 frame mosaic made from a vantage point 32 degrees above the ecliptic plane.

APOD: 2024 September 30 Б Comet Tsuchinshan ATLAS over Mexico
30.09.2024

The new comet has passed its closest to the Sun and is now moving closer to the Earth. C/2023 A3 (TsuchinshanБATLAS) is currently moving out from inside the orbit of Venus and on track to pass its nearest to the Earth in about two weeks.