The Colors of Comet Hyakutake
29.03.1996

The colors of Comet Hyakutake are caused by the action of sunlight on the dust and gas produced by the warming nucleus. The microscopic dust particles reflect sunlight while the sun's ultraviolet radiation excites and ionizes the gas molecules causing them to glow or fluoresce in a range of visible colors.

Galaxies and a Comet
20.10.2023

Galaxies abound in this sharp telescopic image recorded on October 12 in dark skies over June Lake, California. The celestial scene spans nearly 2 degrees within the boundaries of the well-trained northern constellation Canes Venatici.

ZTF meets ATLAS
10.02.2023

Fading as it races across planet Earth's northern skies comet C/2022 E3 (ZTF) shares this telescopic frame with comet C/2022 U2 (ATLAS). Captured on the night of February 6 from a garden observatory in Germany's Bavarian Forest, the starry field of view toward the constellation Auriga spans about 2.5 degrees.

Comet Hyakutake's Past and Future
23.03.1996

The above false-color picture of Comet Hyakutake taken just two days ago shows its rapidly developing tail. The comet now has a substantial coma with a bright center, lending it a dramatic eye-like appearance. This is not Comet Hyakutake's first visit to the inner Solar System.

Anemic Galaxy NGC 4921 at the Edge
9.02.2009

How far away is spiral galaxy NGC 4921? Although presently estimated to be about 320 million light years distant, a more precise determination could be coupled with its known recession speed to help humanity better calibrate the expansion rate of the entire visible universe.

Two Comets in Southern Skies
8.10.2022

Heading for its closest approach to the Sun or perihelion on December 20, comet C/2017 K2 (PanSTARRS) remains a sight for telescopic observers as it sweeps through planet Earth's southern hemisphere skies. First...

Comet Lemmon and the Deep Sky
20.07.2013

Now sweeping high above the ecliptic plane, Comet Lemmon has faded dramatically in planet Earth's night sky as it heads for the outer solar system. Some 16 light-minutes (2 AU) from...

Anemic Spiral NGC 4921 from Hubble
25.11.2013

How far away is spiral galaxy NGC 4921? Although presently estimated to be about 310 million light years distant, a more precise determination could be coupled with its known recession speed to help humanity better calibrate the expansion rate of the entire visible universe.

Sungrazer
26.02.1997

Arcing toward a fiery fate, this Sungrazer comet was recorded by the SOHO spacecraft's Large Angle Spectrometric COronagraph (LASCO) on Dec. 23rd, 1996. LASCO uses an occulting disk, partially visible at the lower...

Sungrazer
20.05.2000

Arcing toward a fiery fate, this Sungrazer comet was recorded by the SOHO spacecraft's Large Angle Spectrometric COronagraph (LASCO) on Dec. 23rd, 1996. LASCO uses an occulting disk, partially visible at the lower...