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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.

A new way to search for exomoons

Schematic of a plasma torus around an exoplanet, which is created by the ions injected from an exomoon's ionosphere into the planet's magnetosphere.   Image via UT Arlington

Schematic of a plasma torus around an exoplanet, which is created by the ions injected from an exomoon’s ionosphere into the planet’s magnetosphere. Image by Suman Satyal via UT Arlington

We now know more than 1,800 exoplanets – worlds orbiting distant suns – but zero exomoons. UT Arlington physicists propose a new way to search for them, based on the behavior of one our solar system’s strangest moon’s, Io.

Lifeform of the week: Death’s-head hawkmoth

Image Credit: Jeffdelonge

Image Credit: Jeffdelonge

It’s the insect star of The Silence of the Lambs.

Weak supernova might have left zombie star

The two inset images show before-and-after images captured by NASA’s Hubble Space Telescope of Supernova 2012Z in the spiral galaxy NGC 1309. The white X at the top of the main image marks the location of the supernova in the galaxy.  Image via NASA, ESA

Here is the spiral galaxy NGC 1309. The two inset images show before-and-after images of Supernova 2012Z, as captured by the Hubble Space Telescope. The white X at the top of the main image marks the location of the supernova in the galaxy. Image via NASA, ESA

Astronomers are scrutinizing a star system in a distant galaxy that exploded, possibly leaving behind a zombie star. They say their study of this system will help them understand supernova explosions, which are an important piece of the cosmic puzzle, used to help measure distances in vast space and the expansion of the universe.

Astronomers watch as storms swirl on distant Uranus

Massive storms on Uranus captured August 5 and 6, 2014 as seen by Keck Observatory. Both images were taken by Imke de Pater (UC Berkeley), Larry Sromovosky and Pat Fry (U. Wisconsin), and Heidi Hammel (AURA) using the near-infrared camera NIRC2 with adaptive optics on the 10-m Keck II telescope at a wavelength of 1.6 micron.

Massive storms on the 7th planet, Uranus, captured August 5 and 6, 2014 at Keck Observatory. Image via Imke de Pater, Larry Sromovosky, Pat Fry, and Heidi Hammel.

Astronomers in Hawaii said they were “surprised” by the many bright, swirling storms they observed this week on the planet Uranus, including at least one “monstrous feature.” It just goes to show we haven’t had the equipment to observe Uranus as carefully as we now can, throughout its 84-year orbit.

Iselle and Julio deliver one-two punch to Hawaii

Iselle and Julio bear down on Hawaii.  NASA image.

Iselle and Julio bear down on Hawaii. NASA image.

Two storms are laying siege to Hawaii today: Iselle and Julio. Iselle was downgraded to a tropical storm as its winds battered Hawaii’s Big Island on Thursday night. The center of the storm had been expected to make landfall Thursday, but remained offshore hours after it had been expected to strike. On its current path, Iselle will deliver a direct hit to Big Island of Hawaii and pass just south of the other islands. Hurricane Julio, with winds of over 100 miles per hour, is close behind. It is expected to reach the Hawaiian Islands over the weekend.

Humid cities are worse urban heat islands than dry cities

Atlanta, Georgia is a hot, humid city in the southeastern US. Image Credit: Ed Schipul.

Atlanta, Georgia is a hot, humid city in the southeastern US. Image Credit: Ed Schipul.

Have you ever been in a hot city in the middle of summer then driven to the country where it is noticeably cooler? That extra heat in the city is what scientists refer to as the urban heat island effect. And humid cities across North America have it worse than dry ones, according to a new study.