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Double Cluster in Perseus: Two star clusters

The Double Cluster is also known as h and Chi Persei. It resides in the northern part of the constellation Perseus, quite close to the constellation Cassiopeia the Queen. If you have a dark sky and find Cassiopeia – which is easy, because the constellation has a distinctive M or W shape – be sure to look for Perseus, too. Then just scan with your binoculars between them. The Double Cluster – a breathtaking pair of clusters, each containing supergiant suns – will be there. Follow the links inside to learn more.

Found Cassiopeia? Now look for Perseus

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If you’re in the Northern Hemisphere, try looking northeast this evening for two prominent constellations, Cassiopeia and Perseus. The easier to see will be Cassiopeia, which has a distinctive M or W shape. Cassiopeia represents a queen in ancient mythology, and is one of the most famous constellations in the sky. You’ll see it in the northeast this evening, and higher up in the evening sky in late fall and winter.

Milky Way’s dark matter half what we thought?

Artist's concept of the halo of dark matter surrounding our Milky Way galaxy.

Artist’s concept of the halo of dark matter surrounding our Milky Way galaxy. Image via ProfMattStrassler.com

Australian astronomers have now chimed in on the subject of why our Milky Way galaxy has fewer orbiting satellites than a prevailing theory of the universe – cold dark matter theory – says it should. They say the reason is that, according to their measurements, there’s only half the amount of dark matter in the Milky Way as previously thought, only 800 billion times the mass of our sun. Their ideas are the latest in a series of widely varying researches, all attempting to explain the “missing” Milky Way satellites.

Lifeform of the week: Owls

Snowy Owl on a snowy day. Image Credit: David Hemmings.

Snowy Owl on a snowy day. Image Credit: David Hemmings.

In fact and in fiction, owls have always turned heads.

MESSENGER spacecraft sees lunar eclipse from Mercury

Earth and Moon from Mercury orbit, with Moon entering eclipse.  Imaged on Wednesday, October 8, 2014 by MESSENGER, a spacecraft in orbit around Mercury.

Earth and Moon from Mercury’s orbit, with moon entering eclipse. Imaged on Wednesday, October 8, 2014 by MESSENGER, a spacecraft in orbit around Mercury. Image via NASA / JHU / APL. MESSENGER

The MESSENGER spacecraft – which has been orbiting the sun’s innermost planet Mercury since 2011 – made this movie of the the Hunter’s Moon passing into the Earth’s shadow on October 8, 2014. The movie consists of 31 MDIS NAC (Mercury Dual Imaging System Narrow Angle Camera) frames taken two minutes apart from 09:18 UTC to 10:18 UTC on October 8. MESSENGER made the movie from a distance of 107 million kilometers / 66 million miles.

Typhoon Vongfong approaching Okinawa

Reid Wiseman took this picture on top of the ISS showing the true power of Super Typhoon Vongfong. Image Credit: Reid Wiseman/Twitter

Reid Wiseman took this picture from top of the International Space Station, showing the true power of Super Typhoon Vongfong. Image via Reid Wiseman (@astro_reid) on Twitter

Earlier this week, Typhoon Vongfong became the strongest storm to form across the globe for 2014. The typhoon became a super typhoon with sustained winds of 180 miles per hour (mph) or 290 kilometers per hour (kph). Vongfong will gradually weaken over the next several days. Unfortunately, it will travel near Okinawa and push over mainland Japan this weekend (October 10-13, 2014) as it pushes off to the northeast. Vongfong will bring with it strong winds, heavy rain and storm surge across the area.

First named feature on a comet!

Close-up of the boulder Cheops as it casts a long shadow on the surface of comet 67P/Churyumov-Gerasimenko. Image via ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Close-up of the boulder Cheops as it casts a long shadow on the surface of Comet 67P/Churyumov-Gerasimenko. Cheops is 45 meters (50 yards) across. The Rosetta spacecraft captured this image on September 19, 2014 from a distance of 28.5 kilometers (17 miles). Image via ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Prior to this past August, we’d never flown side by side with a comet. But now the great Rosetta spacecraft of European Space Agency (ESA) is indeed flying in tandem with Comet 67P/Churyumov-Gerasimenko and will continue to match the comet’s path as it approaches its perihelion – closest point to the sun – in July 2015. Now one of the large boulders observed on the comet’s surface has been named. Scientists are calling it Cheops after the largest pyramid within the Giza Necropolis in Egypt. They gave it this name because it’s one of a cluster of boulders that reminded the scientists of the pyramids of Giza.

One of the sharpest images ever obtained of Mercury

Very closeup look at planet Mercury.  Image obtained on August 3, 2014, via NASA / JHU / APL MESSENGER spacecraft.

Very closeup look at a small crater on the planet Mercury. Image obtained on August 3, 2014, via NASA / JHU / APL MESSENGER spacecraft.

This unnamed crater is only 1.5 kilometers / 0.93 miles wide. It’s made more visible by the deep shadows cast on a Mercury afternoon.

Diverse microbes found deep beneath Antarctic ice sheet

Location of subglacial Lake Whillans

Lake Whillans is located under the Whillans Ice Stream at the southeastern edge of the Ross Ice Shelf in west Antarctica. The lake surface is 800 m (2,600 ft) beneath the surface of the ice.

Nearly 4,000 species of microorganisms were found in the cold, dark waters of Lake Whillans, which sits about half a mile below Antarctica’s ice sheet.

Is the October 8, 2014 full moon a supermoon?

The moon's apparent size in our sky depends on its distance from Earth.  The supermoon of March 19, 2011 (right), compared to an average moon of December 20, 2010 (left).  Image by Marco Langbroek of the Netherlands via Wikimedia Commons.

The moon’s apparent size in our sky depends on its distance from Earth. The supermoon of March 19, 2011 (right), compared to an average moon of December 20, 2010 (left). Image by Marco Langbroek of the Netherlands via Wikimedia Commons.

The astrologer Richard Nolle is credited for coining the term supermoon, which he defines as:

… a new or full moon which occurs with the moon at or near (within 90% of) its closest approach to Earth in a given orbit.

Based on this definition, should the October 8, 2014 full moon be regarded as a supermoon? Experts disagree. Follow the links inside to learn more.