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This date in science: Definitive discovery of Neptune’s rings

Neptune's rings via Voyager 2.

Neptune has a faint, continuous ring system. This Voyager 2 image is shown at increased brightness, to bring out fainter features.

August 22, 1989. When NASA’s Voyager 2 spacecraft skimmed past the planet Neptune on this date, it discovered a faint but continuous ring system encircling the planet. Scientists had suspected there were rings around Neptune some years earlier. After all, Uranus had rings, discovered in 1977. And, watching from Earth in 1984, astronomers were able to see extra blinks before and after Neptune passed in front of a distant star. Still, Voyager 2 made the definitive discovery of Neptune’s rings a few days before it swept closest to the planet.

Unusual precipitation patterns in the U.S.

Portland, ME on Aug. 13, 2014, via Kevin Burns

Portland, Maine on August 13, 2014 via Kevin Burns

Depending on where you live, you could call 2014 the year of the drought, or the year of the deluge. In early August 2014, we have seen several significant rainfall events occur across the United States. During the week of August 10, for example, a slow moving area of low pressure across the Great Lakes and New England produced widespread showers and storms. Yesterday (August 19), parts of Phoenix (yes, the desert) recorded over four inches of rain in a short time period, thanks to an upper level low pushing into the western United States. Are extreme rainfall events related to climate change, and/or has urban sprawl contributed to flash flooding events due to more concrete and poor sewer systems? The answers to both questions are probably yes. Follow the links inside to learn more.

Lifeform of the week: Brain mushroom

Image Credit: Lebrac

Image Credit: Lebrac

The brain mushroom is that rare species with the distinction of being both edible and poisonous.

Curiosity rover is having wheel problems

View larger. | Curiosity rover's left front wheel at Sol 713 - that is, 713 Martian days since the rover touched down on Mars in 2012.

Curiosity rover’s left front wheel at sol 713 – that is, 713 Martian days since the rover touched down on Mars in 2012.

Emily Lakdawala at the Planetary Society posted an in-depth report today (August 19, 2014) about the ongoing wheel problems of NASA’s Mars Curiosity rover, which has been exploring the surface of the Red Planet since its dramatic touchdown just two years ago this month. Lakdawala writes of:

… punctures, fissures, and ghastly tears. The holes in Curiosity’s wheels have become a major concern to the mission, affecting every day of mission operations and the choice of path to Mount Sharp. Yet mission managers say that, so far, the condition of the wheels has no effect on the rover’s ability to traverse Martian terrain.

The risk of an exploding glacier is heating up in Iceland

The first fissure that opened on Fimmvörðuháls, as seen from Austurgígar in 2010. Image credit: David Karnå/Wikimedia Commons

The first fissure that opened on Fimmvörðuháls, as seen from Austurgígar in 2010. Image credit: David Karnå/Wikimedia Commons

Will lava soon hit glacier ice, unleashing an explosion that would spew ash and steam high in the atmosphere? The Icelandic Meteorology Office (IMO) is monitoring Bárðarbunga, a volcano more than 2,000 meters in elevation, located beneath Vatnajökull, the country’s largest glacier. Since midnight on the morning of August 18, the IMO has detected about 950 eart­hqua­kes at Bárðarbunga. Aviation alert code has been raised to orange.

2014 Gulf of Mexico dead zone has grown to 5,052 square miles

Size of the 2014 dead zone in the Gulf of Mexico. Image via LUMCON and Louisiana State University.

Size of the 2014 dead zone in the Gulf of Mexico. Image via LUMCON and Louisiana State University.

Scientists head out to the Gulf of Mexico every summer to measure the size of the dead zone—an area with oxygen levels that are too low to support most marine life.

Exploring the Trifid Nebula

Componets of the Trifid, by Martin MacPhee

Componets of the Trifid, by Martin MacPhee

The Trifid Nebula is a stellar nursery, a cluster of recently born stars, a bright red hydrogen emission nebula, a lovely blue reflection nebula, and an interesting dark nebula divided into 3 …

Awesomeness from the International Space Station

Second, the southern half of Orion the Hunter with the three belt blue supergiant stars Alnitak, Alnilam and Mintaka visible in the Earth's atmosphere. The blue supergiants Saiph and Rigel.  Below the constellation of Lepus the Hare. To the lower left, the constellation of Canis Major, the Great Dog, with the bight stars, Sirius (the brightest object and one of the closest outside of our solar system), powerful blue giant Mirzam, blue supergiant, Adhara (one of the most powerful stars visible from Earth), the huge immensely powerful yellow supergiant Wezen (another one of the most powerful stars visible from Earth) and the blue supergiant Aludra.

View larger. | A crew member of ISS Expedition 40 recorded this nighttime scene on June 23, 2014. Part of the constellation Orion is near the center of the frame.

What would it be like to view the Earth and the sky from the vantage point of the International Space Station? These three photos from ISS tell the tale.

Watch clouds move over a methane sea on Titan

Methane clouds moving above a large methane sea on Saturn's moon Titan.  Image via Cassini.

Methane clouds moving above a large methane sea on Saturn’s moon Titan. Image via Cassini

Between July 20 and 22, 2014, the Cassini spacecraft – which has been orbiting Saturn since 2004 – tracked a system of clouds developing, then dissipating over a methane sea on Saturn’s large moon, Titan. Earthly scientists call this alien northern sea on Titan by the name Ligeia Mare.

What makes a red rainbow?

Göran Strand of Sweden captured this double red rainbow.  Used with permission.

Photo by Göran Strand. Used with permission.

Astrophotographer Göran Strand of Sweden kindly gave us permission to publish this photo, which a phenomenal double red rainbow. Details … inside.