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Moon east of Spica, west of 2 planets at nightfall August 30

Moon moving toward Mars and Saturn on August 30, joins up with Mars and Saturn on August 31 and moves on toward Antares on September 1

Moon moving toward Mars and Saturn on August 30, joins up with Mars and Saturn on August 31 and moves on toward Antares on September 1.

As darkness falls around the world on August 30, look for the star Spica to the west of tonight’s waxing crescent moon. Planets Mars and Saturn are to the east of tonight’s moon. Remember, west is in the direction of sunset.

Iceland volcano eruption begins but no ash cloud. Aviation warning at orange

Iceland’s volcanic eruption as seen from the air. (source: RUV.is)

Iceland’s volcanic eruption as seen from the air. (source: RUV.is)

UPDATE AUGUST 29, 2014. The eruption at the Bárðarbunga volcano began at midnight local time on Friday. Iceland briefly raised its aviation warning level to red, but no volcanic ash has been detected and the level was returned to orange.

Everything you need to know: zodiacal light or false dawn

The zodiacal light – or false dawn – is an eerie light extending up from the eastern horizon, before sunrise, in autumn. You might also see it in the west after sunset, in springtime, in which case it’s called the false dusk. The light looks like a hazy pyramid of light extending up from the horizon. Follow the links inside to learn more about the zodiacal light.

How far is a light-year?

The Orion Nebula, 1,500 light years from Earth. Image credit: NASA/JPL-Caltech/STScI

The Orion Nebula, 1,500 light years from Earth. Image credit: NASA/JPL-Caltech/STScI


Here’s your FAQ for this Friday ….

Light is the fastest-moving stuff in the universe. It travels at an incredible 300,000 kilometers (186,000 miles) per second. That’s very fast. A light-year is the distance light travels in one year. How far is that?

Purple aurora

Photo credit: Göran Strand

Photo credit: Göran Strand

Very beautiful aurora over Östersund, Sweden. We love aurora season!

Moon near star Spica, heading for Mars and Saturn, on August 29

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

As soon as darkness falls on August 29, look low in the southwest sky for the slender waxing crescent moon and the star Spica. Over the next few days, at nightfall, watch for the moon to move away from Spica and toward the planets Mars and Saturn. Be sure to catch the moon and Spica as soon as darkness falls, for the two will follow the sun beneath the horizon shortly thereafter.

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.