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Another breathtaking view of Comet Lovejoy

Comet Lovejoy on December 27, 2015 from the Fermi Dark Energy Camera

Comet Lovejoy on December 27, 2015 from the Fermi Dark Energy Camera. Image via Fermilab’s Marty Murphy, Nikolay Kuropatkin, Huan Lin and Brian Yanny

Fermilab’s Dark Energy Camera took a break from studying one of the greatest mysteries in modern cosmology – dark energy – to capture this stunning view of Comet Lovejoy – an extremely photogenic comet – on December 27, 2014. At the time this image was taken, the comet was passing about 51 million miles from Earth – a short distance for the Dark Energy Camera, which is sensitive to light up to 8 billion light-years away.

Are a star’s brightness and luminosity the same thing?

Image credit: NASA

Image credit: NASA

When we talk about the luminosity of a star, we are referring to the star’s intrinsic brightness. We are not talking about the star’s apparent magnitude – its brightness as it appears from Earth. For instance, most every star that you see with the unaided eye is larger and more luminous than our sun. The stars that we see at night are millions – even hundreds of millions – of times farther away than the sun. Regardless, you can still see these distant suns because many of them are hundreds or thousands of times more luminous than our local star.

Fireball at Sandy Point, Maine

View larger. | A bright meteor, or fireball, at Sandy Point, Maine by Mike Taylor Photo

Bright meteor, or fireball, captured from Sandy Point, Maine by Mike Taylor Photo

Two photographers – Mike Taylor and Sonia MacNeil of Mike Taylor Photo – caught a bright meteor, or fireball, from an icy beach.

Moon inside Winter Circle on February 27

2015-february-27-winter-circle-jupiter-night-sky-chart

The waxing gibbous moon on February 27 resides in or near a large asterism that we in the Northern Hemisphere often call the Winter Circle. It’s an incredibly large star configuration made of brilliant winter stars. From North America on this night, the moon is inside the Circle. If you’re in the Southern Hemisphere … although it’s not winter for you, these same stars appear near the moon.

Beautiful video: Dolphin stampede and whales

A quadcopter drone was used to capture this amazing video a year ago. If you watch it all, you’ll see thousands of common dolphins stampeding off Dana Point, California, three gray whales migrating together down the coast off San Clemente, California, plus, toward the end, close-ups from Maui of a newborn Humpback whale calf snuggling and playing with its mom, as an escort whale stands guard nearby. Definitely worth five minutes!

Moon skims north of Orion on February 26

2015-february-26-orion-moon-night-sky-chart

The waxing gibbous moon will be shining to the north of the constellation Orion the Hunter as darkness falls on February 26, 2015. Yet the moon will be south of the ecliptic – the annual pathway of the sun in front of the backdrop stars.

Mysterious Ceres bright spot is double!

This image was taken by NASA's Dawn spacecraft of dwarf planet Ceres on Feb. 19 from a distance of nearly 29,000 miles (46,000 kilometers). It shows that the brightest spot on Ceres has a dimmer companion, which apparently lies in the same basin. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

This image was taken by NASA’s Dawn spacecraft of dwarf planet Ceres on Feb. 19 from a distance of nearly 29,000 miles (46,000 kilometers). It shows that the brightest spot on Ceres has a dimmer companion, which apparently lies in the same basin. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

As Dawn gets closer to Ceres, the dwarf planet continues to puzzle scientists. Now Ceres’ mysterious bright spot can be seen to have a dimmer companion. The spacecraft arrives March 6.

Watch unusual comet sail past sun

You might be able to see the newly-discovered comet – named C/2015 D1 (SOHO) – in your evening skies. Maybe.

Bright star near moon on February 25 is Aldebaran

Tonight – February 25, 2015 – if you live at far-northern latitudes, you might see the moon hide the star Aldebaran, brightest light in the constellation Taurus, for a portion of the night. In Iceland, Greenland, and northern Europe, the moon will occult – cover over – Aldebaran for up to an hour or so. Not at a far-northern latitude? That’s okay! You’ll have an awesome view of this bright star near tonight’s moon.

When the daytime moon covers Venus

When the moon occulted - over covered over - the planet Venus on June 17, 2007.  Photo by Alfons Gabel.

Time-sequence of when the moon occulted – over covered over – the planet Venus on June 18, 2007. Taken with a 500mm telephoto lens and a DSLR. Photo by Alfons Gabel.

We don’t usually run photos from years ago as our Today’s Image. But this one was just so striking, and, with Venus blazing away in the west after sunset, we figured … yes! On June 18, 2007, the crescent moon eclipsed the planet Venus. Astronomers call this kind of event an occultation of Venus by the moon. The 2007 Venus occultation was visible in broad daylight from Europe …