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Huge asteroid to sweep close on January 26

View larger. | The path of asteroid 2004 BL86 on January 26-27 carries it northward among the winter stars and makes it well positioned for viewing with a backyard telescope. Eastern Standard Time is shown, so be sure to make a time-zone correction for your location.  Translate to your time zone here.  Chart via skyandtelescope.com

The path of asteroid 2004 BL86 on January 26-27 carries it northward among the winter stars and makes it well positioned for viewing with a backyard telescope. Eastern Standard Time is shown, so be sure to make a time-zone correction for your location. Translate to your time zone here. Chart via skyandtelescope.com

Are you ready to witness an asteroid flyby? Although there’s no danger of impact, this one is huge; twice as big as a cruise ship! The asteroid, called 2004 BL86 by astronomers, will sweep safely past Earth on January 26, 2015. It will be the closest of any known space rock this large until asteroid 1999 AN10 flies past Earth in 2027, and it’ll be the closest this particular asteroid will come to Earth for at least the next 200 years. Watch with optical aid, or online. Follow the links inside for more.

What’s a safe distance between us and an exploding star?

Artist's illusration of a supernova via SmithsonianScience.org

Artist’s illustration of a supernova via SmithsonianScience.org

A supernova is a star explosion – destructive on a scale almost beyond human imagining. If our sun exploded as a supernova, the resulting shock wave probably wouldn’t destroy the whole Earth, but the side of Earth facing the sun would boil away. Clearly, the sun’s distance – 8 light-minutes away – isn’t safe. Fortunately, our sun isn’t the sort of star destined to explode as a supernova. But other stars, beyond our solar system, will. What is the closest safe distance? Follow the links inside to learn more.

Little solar halo observer

Photo taken January 22, 2015 by Fotograf Göran Strand.   Visit Göran on Facebook.

Little Solar Halo Observer, taken January 22, 2015 by Fotograf Göran Strand.

Göran Strand in Östersund, Sweden, posted this photo at EarthSky Facebook. He wrote:

Today, a beautiful solar halo was visible around Östersund. Me and my son went out watch it over the frozen lake Storsjön. It was his first full circle solar halo so it was a big moment … also for his daddy.

Moon and stars of Aries point to Phantom galaxy on January 25

2015-jan-25-aries-moon-night-sky-chart

Use the moon on the nights of January 25 and 26, 2015, to find three stars outlining the head of the constellation Aries the Ram (Hamal, Sheratan and Mesartim). Then, when the moon moves out of the evening sky in the second week of February 2015, use these three stars to find an elusive galaxy – Messier 74 – also known as the Phantom galaxy.

Seasons are changing on Rosetta’s comet

Via ESA NAVCAM Rosetta.

Rosetta obtained this image of its comet on January 16. Contrast it to an image inside, and you’ll see how the “seasons” are changing on the comet. Image via ESA NAVCAM Rosetta.

While its Philae Lander continues to ‘sleep,’ waiting for the sun to rise high enough in its sky for its solar panels to begin generating power again, the Rosetta spacecraft continues its science mission at Comet 67P/Churyumov–Gerasimenko. The image above is an amazing four-frame mosaic from Rosetta’s Navigation Camera (NAVCAM), taken on January 16. The orientation of the Rosetta Spacecraft and time of day on the comet is identical to the images obtained back on November 2. Click inside and compare …

Is our Milky Way a wormhole?

Artist's concept by Davide and Paolo Salucci

Artist’s conception of a wormhole by Davide and Paolo Salucci

Scientists, especially astrophysicists, like to know what’s possible in our universe. Their theories and complex computer simulations are aimed at showing what might exist. Today, an international group of researchers said that it’s possible our Milky Way galaxy is a huge wormhole – a space-time tunnel – a galactic transport system to other parts of space. They made that determination by including dark matter – that mysterious something that makes up the bulk of our universe. According to these researchers, when you consider dark matter along with the regular matter in the Milky Way, our galaxy’s density appears great enough to allow for a wormhole at the galaxy’s heart.

Snowy owl on a cold New Hampshire beach

Photo credit: Josh Blash

Photo credit: Josh Blash

Josh Blash captured this shot early on a mid-January morning, at the harbor in Rye, New Hampshire. In the background is sea smoke – formed when very cold air moves over warmer water – and the rocky Isles of Shoals.

Moon and Uranus in front of Pisces on January 24 and 25

2015-jan-24-uranus-moon-night-sky-chart

The waxing crescent moon and planet Uranus, the seventh planet outward from the sun, float in front of the constellation Pisces the Fishes on the evenings of January 24 and 25, 2015. Although Uranus will remain within Pisces’ borders for the rest of this year, the moon will leave Pisces after a few more days. With the moon waxing to full now, you’re not likely to glimpse Uranus with the unaided eye. But click inside, anyway. We give you an idea of its location, and links to detailed charts, in this post.

What are the seasons like on Uranus?

Image via Lawrence Sromovsky / Keck Observatory.

Image via Lawrence Sromovsky / Keck Observatory.

Uranus, like Earth, has four seasons. But that’s where the similarity ends. For starters, each season on Uranus lasts 21 (Earth) years.

Little auks adapt to warming Arctic

Little auks. Photo:  © Allan Hopkins/Flickr

Little auks. Photo: © Allan Hopkins/Flickr

This little bird, that looks kind of like a flying penguin, has got scientists rethinking how polar ecosystems are changing in our warming world.