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What to expect as Rosetta spacecraft approaches its comet

Comet 67P on July 14, 2014

Comet 67P/Churyumov-Gerasimenko on July 14, 2014

Rosetta’s scientific imaging system captured this image of Comet 67P/Churyumov-Gerasimenko last week, on July 14, 2014, from a distance of approximately 12,000 kilometers (8,000 miles). But the best is yet to come. Expect the next image last this week. By August, the Rosetta spacecraft will be moving side by side with its comet. In November, it’ll send a lander to the comet’s surface!

Rising Milky Way, laser light show, Singapore, July 21

The Milky Way, and a laser light show, over Singapore July 21, 2014.  Photo by Justin Ng.  For more about this photo, visit Justin Ng's blog.

The Milky Way, and a laser light show, over Singapore. Photo by Justin Ng.

Justin Ng captured this beautiful scene last night (July 21, 2014) It’s another of his “impossible” shots – that is, photos that inspire more astrophotographers in light-polluted cities to unveil the beauty of the elusive Milky Way galaxy.

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!

lnside the mysterious Yamal crater

The crater, which is 70 meters deep, has an icy lake at its bottom.  Photo by Andrey-Naumenko via Siberian Times.

The crater, which is 70 meters deep, has an icy lake at its bottom. Photo by Andrey-Naumenko via Siberian Times.

The mysterious crater on the Yamal peninsula, discovered by helicopter last week, is not as wide as original aerial estimates suggested. It is now thought to be about 30 meters wide, in contrast to original estimates of up to 100 meters. However, the crater is now known to be up to about 70 meters deep, and it’s seen to have an icy lake at its bottom, with water cascading down its eroding permafrost walls.

Does Earth have a second moon?

Image of Earth with two moons, generated in Celestia software, by Grebenkov in Wikimedia Commons.

Many planets in our solar system have more than one moon. Mars has two moons, Jupiter has 66, Saturn 62, Uranus 27, Neptune 13. But our planet Earth has just one moon. Doesn’t it?

Longest lunar month of 2014 starts on August 25

Simulated view of the cycle of the moon's phases from new moon to new moon. This cycle is known as the lunar month. From the years 1760 to 2200, the longest lunar month was 29 days 19 hours and 58 minutes and the shortest 29 days 6 hours and 34 minutes.

Simulated view of the moon’s phases. The period of time from new moon to new moon is known as the lunar month, lunation or synodic month. From the years 1760 to 2200, the longest lunar month spans 29 days 19 hours and 58 minutes (Dec. 9, 1787 to Jan. 8, 1778) while the shortest lasts for 29 days 6 hours and 34 minutes (June 12 to July 12, 1885).

The longest lunar month of the year begins with the new moon of August 25, 2014, and ends with the new moon of September 24, 2014. This lunar month – the period of time between successive new moons – lasts for 29 days 16 hours and 1 minute. That’s 3 hours and 17 minutes longer than the mean lunar month of 29 days 12 hours and 44 minutes.

Keep watching east before dawn as moon sweeps past planets

On Wednesday morning, July 23, the moon is between the star Aldebaran and the planet Venus.  Look east before dawn.

On Tuesday morning, July 22, the moon is near the star Aldebaran. On Wednesday morning, July 23, the moon is between Aldebaran and the planet Venus. Look east before dawn.

If you’re an early riser, you might know that the old moon has been back in the east before dawn this week. What to expect in the coming mornings, inside.

Transiting exoplanet with longest year yet

Kepler-421b orbits an orange, type K star that is cooler and dimmer than our sun. It circles the star at a distance of about 110 million miles. As a result, this Uranus-sized planet is chilled to a temperature of -135° Fahrenheit.  Caption and illustration via CfA.

The transiting exoplanet with the longest known year is Kepler-421b. It orbits an orange, type K star that is cooler and dimmer than our sun, circling its star at a distance of about 110 million miles. This world is thought to be about the size of Uranus, or about four times larger than Earth. Its surface temperature is estimated at a chilly -135° Fahrenheit. Illustration via CfA.

The techniques for finding exoplanets – or planets orbiting distant stars – favor the discovery of large planets orbiting close to their stars. That’s why astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) were pleased to announce today (July 21, 2014) that they’ve found an exoplanet whose “year” lasts 704 days. That is the longest orbit of any exoplanet discovered via transit to date.