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Intriguing cycle of close and far moons

View larger. | Image via Wikipedia.

Image via Wikipedia.

This is why the moon is so ‘super’ tonight. This post explains lunar perigee and includes dates of all closest and farthest moons for each month of 2015.

Milky Way’s black hole is more active!

Image via Chandra X-Ray Observatory

The black hole at the center of our home galaxy, the Milky Way. Image via Chandra X-Ray Observatory

The black hole at the heart of Milky Way – called Sagittarius A* or Sgr A* for short – has within the past year blasted out 10 times its normal rate X-ray flares. Astronomers speculate that the increase in X-rays might be due to the close passage of a mysterious, dusty object that they call G2. But they’re not sure.

Photos from friends: Signs of autumn

Autumn dawn. Dave Sodano wrote,

Autumn dawn. Dave Sodano wrote, ” Went to Steamboat Springs Colorado this weekend in search of fall colors. Found this instead. The 1st cold night of the season on a summer warm lake produced this lovely mist and deep morning colors.”

Thank you to EarthSky friends for posting your wonderful photos showing the signs of autumn. Happy autumn (or spring, if you’re in the Southern Hemisphere) to everyone on this day of the equinox!

Amazing, blazing equinox sunset

I was tempted by EarthSky’s extensive coverage on the equinoxes to check out and photograph the equinox sunset here in Mutare, Zimbabwe on September 22, 2015 and recorded much more than anticipated. To my surprise it turned out to be literally a blazing one due to the fortuitous occurrence of a bush fire concealed behind the exact point on the hill over which the sun went down.

Watch an exoplanet orbit its star

This video is made from a series of images captured between November 2013 and April 2015, and it shows an exoplanet, a planet orbiting a distant star, moving through 18 months of its 22-year orbit around its star. The star is called called Beta Pictoris, and it’s visible, faintly, in the night sky seen from Earth’s Southern Hemisphere. The exoplanet is called Beta Pictoris b.

Fact and fiction of Martian dust storms

View larger. | Artist's concept of a dust storm on Mars.

Artist’s concept of a dust storm on Mars via NASA.

Andy Weir’s great science fiction book The Martian – soon to be released as a movie – has as its premise that a large Martian dust storm strands an astronaut on Mars. Martian dust storms would be unlikely to do that, but they do have consequences for spacecraft on Mars now, and for future Martian astronauts.

New tree of life for 2.3 million species

A draft of a new

A draft of a new evolutionary “tree of life” via Astrobiology.com.

This initial draft – a collaborative effort from scientists at 11 institutions – is based on nearly 500 smaller trees from previously published studies. Click inside to learn more about it.

2015 wildfire season a record-breaker

Smokey sunset, August , 2015, from EarthSky community member Chris Levitan Photography.

Smokey sunset, August , 2015, from EarthSky community member Chris Levitan Photography in Oregon.

The 2015 wildfire season in the United States has already broken records. So far this year, more acres of land have burned as of mid-September than the total annual amount in 2011, which was the 4th worst year for wildfires at least since the 1960s. So will this year be the new fourth worst, third worst, second worst, or worst wildfire year since then? Read on, and take a guess.

Why aren’t day and night exactly equal at the equinox?

January 1, 2015 sunset by Helio de Carvalho Vital in Rio de Janeiro, Brazil.  Shot 3 of 6.

Flattened sunset by Helio de Carvalho Vital in Rio de Janeiro, Brazil. A flattened sunset is an effect of atmospheric refraction. Refraction also gives us a few more minutes of daylight on the equinox than we would have otherwise.

Twice a year – on the March and September equinoxes – everyone worldwide supposedly receives 12 hours of day and 12 hours of night. Yet, in actuality, there is more daylight than nighttime on the day of the equinox. In fact, at mid-temperate latitudes, there is an additional 8 or so minutes of daylight. Why? There are two reasons why we have more than 12 hours of daylight on the day of the day of supposedly equal day and night. Click to find out….

Video: The solar system to scale

At first I thought I wouldn’t watch this, because it’s 7 minutes long. But then I did watch it, and I’m glad I did, because it’s a beautiful and touching depiction of the relationship between solid matter and empty space in our solar system.