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Iron from Sahara dust helps fertilize Atlantic Ocean

A dust plume from the Sahara desert. Image Credit: NASA.

A dust plume from the Sahara desert. Image Credit: NASA.

Scientists have found that 71% to 87% of the iron in seawater from the North Atlantic may have originated from dust in the Sahara desert.

Pluto-bound New Horizons update

Pluto and Charon as captured by the New Horizons' spacecraft LORRI camera on July 21, 2014.

The two tiny dots at the center of this image are Pluto and Charon as captured by the New Horizons spacecraft LORRI camera on July 21, 2014.

Pluto and Charon seen dead center in this one-quarter-resolution frame from New Horizons’ LORRI (LOng Range Reconnaissance Imager) Camera. Charon is at the four o’clock position with respect to Pluto. Pluto and Charon were 426.51 million kilometers / 264.86 million miles away at the time from New Horizons and appeared in front of the stars in southern Ophiuchus. The spacecraft is out of hibernation temporarily now, and will remain so through August.

As Comet Siding Spring approaches Mars, NASA gets ready

An illustration of the inner part of the orbit of comet C/2013 A1 Siding Spring.  On October 19, 2014, the comet will have a close pass of the planet Mars.  Its nucleus will miss Mars by about 82,000 miles (132,000 kilometers). The comet's trail of dust particles shed by the nucleus might be wide enough to reach Mars or might also miss it.   Image via NASA/JPL.

An illustration of the inner part of the orbit of comet C/2013 A1 Siding Spring. Image via NASA/JPL.

One of the most anticipated astronomical events of 2014 is the close passage of Comet C/2013 A1 Siding Spring to the planet Mars on October 19, 2014. The comet’s tiny nucleus, or core, will miss Mars by about 82,000 miles (132,000 kilometers). As comets travel through space, though, they leave behind a trail of dust particles, and this trail of debris might be wide enough to reach Mars and encounter its thin atmosphere … or might miss it, too. Follow the links inside to learn more.

As Rosetta approaches its comet, a bright ‘neck’ and hilly terrain

View larger. | Comet 67P/Churyumov–Gerasimenko .  Imaged: Sunday 20 July 2014.

View larger. | Comet 67P/Churyumov–Gerasimenko as imaged by the Rosetta spacecraft on July 20, 2014.

UPDATE July 25, 2014. Some real detail is beginning to show. This image shows the 3.5-by-4-km-sized nucleus of the comet seen closer in at a distance of 5,500 kilometers / 3,400 miles by the Rosetta Mission OSIRIS NAC camera. Surface features on the nucleus are now becoming apparent in these 100-meter resolution images. Looks like the impact crater suspected on the bulbous lobe does exist, and there appear to be some linear depressions and hills on the larger lobe. Both lobes are beginning to show hilly terrain.

Camelopardalids: Just a few centuries late in catching a good show

Frame-by-frame development of a Camelopardalid on 2014 May 24 at 01h58m08s UT. Original recording by Peter C. Slansky; compilation by Jim Albers and Peter Jenniskens.

Frame-by-frame development of a Camelopardalid on 2014 May 24. Scientists who studied the meteors said they ‘dispersed into a cloud of dust.’ Illustration via Peter C. Slansky, Jim Albers and Peter Jenniskens.

Want to watch meteors? You’re in luck. Summer meteor season 2014 is just starting.

The SETI Institute has released new information about the Camelopardalid meteor shower. Remember the Camelopardalids? It was that meteor shower last May – the result of a close passage of Comet 209P/LINEAR – that astronomers predicted would be spectacular … except it wasn’t. Now these same astronomers are saying that, although the weak display of Camelopardalids disappointed backyard observers, this never-before-seen shower has them excited. Sigh. Okay, here’s what they say.

Lifeform of the week: Sea stars

I’m not sure exactly when starfish began insisting on being called “sea stars”, but somewhere along the line they got it into their heads (or central disks perhaps, they don’t have heads per se) that since they are not actually fish, they should no longer be addressed as such. This despite the fact that prairie dogs and sea horses are graciously carrying on with their misleading monikers to spare society the trouble of learning new names.

Reservoir of molten rock under Yellowstone is 2.5 times bigger than thought

Midway Geyser Basin, Yellowstone National Park. Image Credit: Neal Herbert, National Park Service.

Midway Geyser Basin, Yellowstone National Park. Image Credit: Neal Herbert, National Park Service.

Yellowstone National Park and the surrounding area is the site of some of the most powerful volcanic eruptions to have ever occurred on Earth. Thanks to new seismic sensors that have been installed in this area over the past decade, scientists now have better tools to visualize what lies beneath the surface. The latest string of research has found that the reservoir of magma – molten or semi-molten rock – under Yellowstone is about 2.5 times bigger than previously thought.

At twilight … 15 best photos

Photo: Joe Randall

Photo: Joe Randall

Twilight is the time of day between daylight and darkness, whether after sunset or before sunrise. The sun is below the horizon, but its rays are scattered by Earth’s atmosphere to create twilight’s pinks, purples, and blues.

These photos all came from our Facebook friends. You’ll love them!

You’ve got to see these mammatus clouds

Josh Blash caught these mammtus clouds illuminated by lightning over Rye, New Hampshire on July 4, 2014.

View larger. | Josh Blash caught these mammatus clouds illuminated by lightning over Rye, New Hampshire.

Josh Blash called this photo “Mammatus Illumination,” and he wrote:

Here is a lightning shot I took around 12 a.m. on July 4, when storms were moving off the New Hampshire coast. I couldn’t see it at the time, but after looking at my photos I believe these are mammatus clouds being illuminated by lightning.

Rammasun hits China as a super typhoon

Visible satellite image showing Rammasun approaching China on 7/17/14. Image Credit: NASA

Visible satellite image showing Rammasun approaching China on 7/17/14. Image Credit: NASA

The China Meteorological Administration said Rammasun was a super typhoon as it made landfall in Hainan – an island in the southernmost province of China – today (July 18, 2014) at around 6 a.m. EDT (1000 UTC). At that time, it had a sustained wind of 155 mph with gusts near 190 mph. Rammasun, also known as Glenda in the Philippines, struck that country earlier this week as a Category 3 storm.