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NROA astronomers pin down distance to Pleiades stars

A telescopic view of the Pleiades, or Seven Sisters.  The eye sees this cluster as a tiny, misty dipper of stars.  It is one of the most beloved star clusters.  Image via NOAO/AURA/NSF.

A telescopic view of the Pleiades, or Seven Sisters. The eye sees this cluster as a tiny, misty dipper of stars. It is one of the most beloved star clusters. Image via NOAO/AURA/NSF.

Astronomers at the National Radio Astronomy Observatory have used a worldwide network of radio telescopes to find the distance to the Pleiades star cluster, also known as the Seven Sisters. The result of their work is a distance to the Pleiades of 443 light-years, accurate, the astronomers said, to within one percent. They say this is the most accurate and precise measurement yet made of the Pleiades’ distance and that is resolves a controversy over the distance to this famous, beloved and important star cluster.

Snowfall ahead in a warmer world, says study

Image credit: Christine Daniloff/MIT

Image credit: Christine Daniloff/MIT

An MIT study finds big snowstorms will still occur in the Northern Hemisphere despite global warming.

Star of the week: 61 Cygni is the Flying Star

The orbital motion of component B relative to component A as seem from Earth as well as the true appearance from face-on view. The time steps are approximately 10 years.  Illustration via Wikimedia Commons

The orbital motion of component B relative to component A as seem from Earth as well as the true appearance from face-on view. The time steps are approximately 10 years. Illustration via Wikimedia Commons

This star, 61 Cygni isn’t among the brightest stars. In fact, it takes some effort just to find it, because it is not much brighter than the faintest stars visible to the unaided human eye. It is, however, among the most important of stars visible without optical aid. It has one of the largest proper motions – that is, sideways motions along our line of sight – of any star in our sky. Its large proper motion has given 61 Cygni the nickname Flying Star. Follow the links inside to learn more.

Report: Summer ozone to get much worse in next 35 years

A new report warns of a 70% increase in the number of days with unhealthy summertime ozone levels by the year 2050.

Activity continues at worrisome Iceland volcano

Fracture in the ice, possibly caused by recent earthquakes, in Holuhraun north of Dyngjujökull glacier in Iceland.  Photo: Tobias Dürig/Institute of Earth Sciences

Fracture in the ice, possibly caused by recent earthquakes, in Holuhraun north of Dyngjujökull glacier in Iceland. Photo: Tobias Dürig/Institute of Earth Sciences

Aerial surveys this week revealed a row of deep cauldrons south of the Bárðarbunga caldera. They are also seeing fractures in glacier ice near the volcano. Bárðarbunga volcano has shown signs for nearly two weeks that an eruption might be imminent, but no eruption yet. An eruption from this sub-glacial volcano could shut down air traffic.

Sea clouds at sunset

Photo credit: Maranatha.it Photography

Photo credit: Maranatha.it Photography

Isn’t this gorgeous? Clouds at sunset over Italy’s Ligurian Sea by Maranatha.it Photography.

Moon and star Spica low in west after sunset August 28

2014-aug-27-28-29-mercury-spica-multiple-moon-night-sky-chart

Look westward as soon as darkness falls on August 28 to catch the slender waxing crescent moon fairly close the horizon. That bright star close to the moon is Spica, the brightest in the constellation Virgo the Maiden. Don’t delay, though, when looking of the moon and Spica, especially if you live at northerly latitudes, for the twosome will follow the sun beneath the horizon by early evening.

Yellowstone supervolcano would cover North America in ash

An example of the possible distribution of ash from a month-long Yellowstone supereruption. The distribution map was generated by a new model developed by the U.S. Geological Survey using wind information from January 2001. The improved computer model, detailed in a new study published in Geochemistry, Geophysics, Geosystems, finds that the hypothetical, large eruption would create a distinctive kind of ash cloud known as an umbrella, which expands evenly in all directions, sending ash across North America. Ash distribution will vary depending on cloud height, eruption duration, diameter of volcanic particles in the cloud, and wind conditions, according to the new study.  Image via USGS

An example of the possible distribution of ash from a month-long Yellowstone supereruption. The U.S. Geological Survey created a new computer model showing this distribution. Their work showed that a hypothetical, large eruption would create a distinctive kind of ash cloud known as an “umbrella,” which expands evenly in all directions. Ash distribution will vary depending on cloud height, eruption duration, diameter of volcanic particles in the cloud, and wind conditions, according to the new study. Image via USGS

Despite the high interest in it, scientists say it’s not likely a supervolcano will erupt at Yellowstone National Park anytime in the near future. And, if one did, the effects of the eruption would vary depending on the strength of the eruption, wind conditions at the time, and other factors. Still, a Yellowstone supervolcano could cover North America with ash, from sea to sea.

No double moon on August 27

This image is circulating on Facebook, with the claim that Mars will appear as big and bright as a full moon on August 27, 2013.  It's a hoax.  Don't believe it.  Mars never appears as large as a full moon in Earth's sky.

This image sometimes circulates on Facebook, with the claim that Mars will appear as big and bright as a full moon on August 27, 2014. It’s a hoax. Don’t believe it. Mars never appears as large as a full moon in Earth’s sky.

The famous double moon on August 27 hoax has come through like gangbusters this August. No one expected that! This hoax is now 11 years old. Still, clearly, not everyone knows it’s a hoax. Google searches have made this post the most popular on our site for the past week. An email must be circulating – somewhere, social media must be buzzing – with the suggestion that – on August 27, 2014 – Mars will appear as large as a full moon in Earth’s sky. And that is just not true.

Evidence for supernovas near Earth

A NASA sounding rocket has confirmed that the solar system is inside an ancient supernova remnant. Life on Earth survived despite the nearby blasts.