A Black Hole Disrupts a Passing Star

What happens to a star that goes near a black hole? If the star directly impacts a massive black hole, then the star falls in completely — and everything vanishes. More likely, though, the star goes close enough to have...

/ March 24, 2020

From the Pleiades to the Eridanus Loop

If you stare at an interesting patch of sky long enough, will it look different? In the case of Pleiades and Hyades star clusters — and surrounding regions — the answer is: yes, pretty different. Long duration camera exposures reveal...

/ March 23, 2020

Moon Setting Behind Teide Volcano

These people are not in danger. What is coming down from the left is just the Moon, far in the distance. Luna appears so large here because she is being photographed through a telescopic lens. What is moving is mostly...

/ March 22, 2020

Comet ATLAS and the Mighty Galaxies

Comet ATLAS C/2019 Y4 was discovered by the NASA funded Asteroid Terrestrial-impact Last Alert System, the last comet discovery reported in 2019. Now growing brighter in northern night skies, the comet’s pretty greenish coma is at the upper left of...

/ March 21, 2020

Morning, Planets, Moon, and Montreal

Dawn’s early light came to Montreal, northern planet Earth, on March 18, the day before the vernal equinox. At the end of that nearly equal night the Moon stands above a dense constellation of urban lights in this serene city...

/ March 20, 2020

M13: The Great Globular Cluster in Hercules

In 1716, English astronomer Edmond Halley noted, “This is but a little Patch, but it shews itself to the naked Eye, when the Sky is serene and the Moon absent.” Of course, M13 is now less modestly recognized as the...

/ March 19, 2020

Anticrepuscular Rays over Florida

What’s happening behind those clouds? Although the scene may appear somehow supernatural, nothing more unusual is occurring than a Sun setting on the other side of the sky. Pictured here are anticrepuscular rays. To understand them, start by picturing common...

/ March 18, 2020

M77: Spiral Galaxy with an Active Center

What’s happening in the center of nearby spiral galaxy M77? The face-on galaxy lies a mere 47 million light-years away toward the constellation of the Sea Monster (Cetus). At that estimated distance, this gorgeous island universe is about 100 thousand...

/ March 17, 2020

A Moon Dressed Like Saturn

Why does Saturn appear so big? It doesn’t — what is pictured are foreground clouds on Earth crossing in front of the Moon. The Moon shows a slight crescent phase with most of its surface visible by reflected Earthlight known...

/ March 16, 2020

The Snows of Churyumov Gerasimenko

You couldn’t really be caught in this blizzard while standing by a cliff on Churyumov-Gerasimenko. Orbiting the comet — frequently abbreviated as 67P or CG — in June of 2016, the Rosetta spacecraft’s narrow angle camera did record streaks of...

/ March 15, 2020