NGC 4414: A Flocculent Spiral Galaxy
19.11.2016

How much mass do flocculent spirals hide? The featured true color image of flocculent spiral galaxy NGC 4414 was taken with the Hubble Space Telescope to help answer this question. The featured image was augmented with data from the Sloan Digital Sky Survey (SDSS).

Gaia: Here Comes the Sun
25.09.2016

What would it look like to return home from outside our galaxy? Although designed to answer greater questions, recent data from ESA's robotic Gaia mission is helping to provide a uniquely modern perspective on humanity's place in the universe.

Perihelion Approaches
14.08.2015

This dramatic outburst from the nucleus of Comet 67P/Churyumov-Gerasimenko occured on August 12, just hours before perihelion, its closest approach to the Sun. Completing an orbit of the Sun once every 6.45 years, perihelion distance for this periodic comet is about 1.3 astronomical units (AU), still outside the orbit of planet Earth (at 1 AU).

APOD: 2025 February 18 Б Thors Helmet versus the Seagull
17.02.2025

Seen as a seagull and a duck, these nebulae are not the only cosmic clouds to evoke images of flight. But both are winging their way across this broad celestial landscape, spanning almost 7 degrees across planet Earth's night sky toward the constellation of the Big Dog (Canis Major).

The Comets Of SOHO
24.02.2000

After four years of successful sun-gazing, the space-based SOlar and Heliospheric Observatory (SOHO) has also become the most successful comet-hunter in history, racking up 102 new comets. Above are examples of SOHO's comet discoveries imaged by LASCO, an on-board coronagraph.

Parker vs Perseid
15.08.2018

The brief flash of a bright Perseid meteor streaks across the upper right in this composited series of exposures made early Sunday morning near the peak of the annual Perseid meteor shower.

SN 2005ap: The Brightest Supernova Yet Found
16.10.2007

What could cause a bang this big? This supernova explosion was so inherently bright that it could be seen nearby 5 billion light years away (a redshift of 0.28) even with a small telescope.

Unicorn, Fox Fur and Christmas Tree
24.12.2025

A star forming region cataloged as NGC 2264, this beautiful but complex arrangement of interstellar gas and dust is about 2,700 light-years distant in the faint but fanciful constellation Monoceros, the Unicorn. Seen...

APOD: 2023 March 22 Б M31: The Andromeda Galaxy
21.03.2023

How far can you see? The most distant object easily visible to the unaided eye is M31, the great Andromeda Galaxy, over two million light-years away. Without a telescope, even this immense spiral galaxy appears as an unremarkable, faint, nebulous cloud in the constellation Andromeda.

Schwassmann Wachmann 3: Fragment B
4.05.2006

Periodic comet 73P/Schwassmann-Wachmann 3 has fallen apart before. A cosmic souffle of ice and dust left over from the early solar system, this comet was seen to split into several large pieces during the close-in part of its orbit in 1995.