Hydrogen Sulfide and Dust Plumes on Namibia's Coast

Cloudless skies allowed a clear view of dust and hydrogen sulfide plumes along the coast of Namibia in early August 2010. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this natural-color image on Aug. 10, 2010.




Multiple dust plumes blow off the coast toward the ocean, most or all of them probably arising from streambeds. Unlike the reddish-tan sands comprising the dunes directly south of the Kuiseb River, the stream-channel sediments are lighter in color. Wind frequently pushes dust plumes seaward along the Namibian Coast. Easterly trade winds blow from the Indian Ocean over the African continent, losing much of their moisture as they go. The winds are hot and dry as they pass over Namibia’s coastal plain, where they are prone to stir fine sediments.



Even with dust plumes overhead, the marked change in land cover is obvious along the Kuiseb River. South of the river, sand dunes predominate, but the vegetation along the Kuiseb River prevents the dunes from advancing northward. North of the river, the land surface consists primarily of gravel plains punctuated by rocky hills.



Hydrogen sulfide appears as a swath of irridescent green running parallel to the coast north of Walvis Bay. A 2009 study linked the emissions in this region to ocean currents, biological activity in the water column, and carbon-rich organic sediments under the water column. The meeting of hydrogen sulfide gas and oxygen-rich surface waters causes pure sulfur to precipitate into the water. The sulfur’s yellow color makes the water appear green to the satellite sensor.

Image Credit: NASA

Discovery's Processing Goes Smoothly Ahead of Rollover

Space shuttle Discovery continues its launch processing on pace as technicians prepare the spacecraft for its scheduled move on Sept. 8 to the Vehicle Assembly so it can be hoisted into launch position with its external fuel tank and solid rocket boosters. Today's work at NASA's Kennedy Space Center includes checks of the "glass cockpit" systems, known as MEDS for Multifunction Electronic Display Subsystem. Technicians also are pressurizing the main landing gear.




At NASA's Johnson Space Center, STS- 133 astronauts will continue working on spacewalk procedures in the Neutral Buoyancy Laboratory.

Anaxagoras Crater

This image from the Lunar Reconnaissance Orbiter shows the floor of the moon's Anaxagoras crater, including a portion of the crater's anorthositic central uplift. The boulders perched on ridges are eroding out of densely fractured bedrock. This image was taken by the Lunar Reconnaissance Orbiter Camera, or LROC, which consists of a pair of narrow-angle cameras and a single wide-angle camera. The mission is expected to return over 70 terabytes of image data.

Image Credit: NASA/GSFC/Arizona State University

Leak checks on Discovery

Working inside Orbiter Processing Facility-3 at NASA's Kennedy Space Center in Florida, technicians are beginning a three-day leak test of space shuttle Discovery's entry closed loop gaseous nitrogen life support system. Tonight, workers will perform a similar test of the spacecraft's external tank umbilical. The shuttle's glass cockpit displays also are undergoing testing. Discovery is slated to be carried to the Vehicle Assembly Building on Sept. 8. Launch is targeted for Nov. 1.

 

The six STS-133 mission astronauts are in the fixed-base simulator at NASA's Johnson Space Center in Houston, the training base for NASA's astronauts. The crew is rehearsing the installation of ELC-4, a procedure they will perform during the mission to the International Space Station.

Discovery's Closeout Work Proceeding

Fri, 20 Aug 2010 07:19:46 -0500

Spacecraft preparations are moving ahead as technicians at NASA's Kennedy Space Center in Florida perform closeout work in the aft and forward sections of the space shuttle Discovery. The shuttle is slated to be carried to the Vehicle Assembly Building on Sept. 8 where it will be connected to its external fuel tank and a pair of solid rocket boosters. Liftoff is targeted for Nov. 1.

Discovery's astronauts will rehearse the first spacewalk of the mission inside the large pool at Johnson Space Center's Neutral Buoyancy Laboratory in Houston.

Techs to Close Discovery's Payload Bay Doors

The Ku-band antenna that transmits audio, video and data between Earth and the space shuttle will be stowed today inside shuttle Discovery's payload bay before the clamshell doors are closed. The antenna, which resembles a mini-satellite dish, is on a stanchion that folds out from the forward bulkhead inside the cargo bay after the spacecraft reaches orbit. The antenna stowage and door closure are part of the ongoing work at NASA's Kennedy Space Center in Florida to prep Discovery for its roll over to the Vehicle Assembly Building next month. There is will be joined to an external fuel tank and a set of solid rocket boosters for launch on the STS-133 mission. Liftoff is targeted for Nov. 1.

The astronauts of STS-133 are working through a simulated entry and landing today at their training base at NASA's Johnson Space Center in Houston. Such simulations, performed inside a moving replica of a shuttle flight deck, are made as realistic as possible and often force crew members to deal with emergency situations in a safe environment.

Sailing Amongst the Stars

Making the stuff of science fiction into reality, NASA engineers are testing solar sails--a unique propulsion technology that one day could enable deep space missions. Much like the wind pushing a sailboat through water, solar sails rely on sunlight to propel vehicles through space. The sail captures constantly streaming solar particles, called photons, with giant sails built from a lightweight material. Over time, the buildup of these particles provides enough thrust for a small spacecraft to travel in space.

 

This image is of a four-quadrant solar sail system, measuring 66 feet on each side that is being tested in the world's largest vacuum chamber at NASA's Glenn Research Center at Plum Brook Station in Sandusky, Ohio.

Image Credit: NASA

Shuttle Missions' Wakeup Songs

NASA Asks Public for Final Shuttle Missions' Wakeup Songs HOUSTON -- If you like music, the space program and are a little nostalgic, NASA has the perfect opportunity for you. For the first time, the public can help choose songs to wake up the astronauts during the last two scheduled space shuttle missions.

 

Traditionally, the songs played to wake up the astronauts are selected by friends and family of the crews. For the last two scheduled missions, NASA is inviting the public to visit the "Wakeup Song Contest" website to select songs from a list of the top 40 previous wakeup calls or to submit original tunes for consideration. To vote or submit a song, visit:

https://songcontest.nasa.gov/

The two songs with the most votes from the top 40 list will be played as crew wakeup calls on the final scheduled flight of space shuttle Discovery. Discovery's STS-133 mission is targeted to launch on Nov. 1.

 

"We're looking forward to hearing which songs the public wants played for us," STS-133 Commander Steve Lindsey said. "It's going to be a difficult choice, because there have been so many great songs played over the years."

Original songs must have a space theme and be submitted to NASA by 4 p.m. CST on Jan. 10, 2011. The songs will be reviewed by agency officials and the top finalists put to a public vote. The top two songs will be used to wake space shuttle Endeavour's STS-134 crew.

Endeavour's mission is the last scheduled space shuttle flight. It is targeted to launch on Feb. 26, 2011.

 

"Space shuttle crews really enjoy the morning wake-up music," STS-134 Commander Mark Kelly said. "While we don't have the best quality speaker in the space shuttle, it will be interesting to hear what the public comes up with. We are looking forward to it."

The song contest campaign follows NASA's ongoing "Face in Space" project. It invites the public to send electronic images of their faces into orbit aboard one of the final remaining space shuttle missions. To submit your image, visit:

http://faceinspace.nasa.gov/

For more information about the Space Shuttle Program and the STS-133 and STS-134 missions to the International Space Station, visit:

http://www.nasa.gov/shuttle

For spaceflight souvenirs visit the SPACEBOOSTERS Online Store

Massive Attack

This image shows the eruption of a galactic “super-volcano” in the massive galaxy M87, as witnessed by NASA's Chandra X-ray Observatory and NSF's Very Large Array (VLA). At a distance of about 50 million light years, M87 is relatively close to Earth and lies at the center of the Virgo cluster, which contains thousands of galaxies.

The cluster surrounding M87 is filled with hot gas glowing in X-ray light (and shown in blue) that is detected by Chandra. As this gas cools, it can fall toward the galaxy's center where it should continue to cool even faster and form new stars.

However, radio observations with the VLA (red) suggest that in M87 jets of very energetic particles produced by the black hole interrupt this process. These jets lift up the relatively cool gas near the center of the galaxy and produce shock waves in the galaxy's atmosphere because of their supersonic speed. The interaction of this cosmic “eruption” with the galaxy's environment is very similar to that of the Eyjafjallajokull volcano in Iceland that occurred in 2010. With Eyjafjallajokull, pockets of hot gas blasted through the surface of the lava, generating shock waves that can be seen passing through the grey smoke of the volcano. This hot gas then rises up in the atmosphere, dragging the dark ash with it. This process can be seen in a movie of the Eyjafjallajokull volcano where the shock waves propagating in the smoke are followed by the rise of dark ash clouds into the atmosphere.

In the analogy with Eyjafjallajokull, the energetic particles produced in the vicinity of the black hole rise through the X-ray emitting atmosphere of the cluster, lifting up the coolest gas near the center of M87 in their wake. This is similar to the hot volcanic gases drag up the clouds of dark ash. And just like the volcano here on Earth, shockwaves can be seen when the black hole pumps energetic particles into the cluster gas.

Image Credits: X-ray: NASA/CXC/KIPAC/N. Werner et al Radio: NSF/NRAO/AUI/W. Cotton

Tests for PDU Replacement

Wed, 18 Aug 2010 07:56:59 -0500

At NASA Kennedy Space Center's Orbiter Processing Facility-3, crews will test the centerline latch power drive unit, or PDU, actuator that was replaced yesterday on space shuttle Discovery. Then technicians will begin preparations to close the spacecraft's payload bay doors one last time before the spacecraft is moved to the Vehicle Assembly Building next month to be joined to its external fuel tank and solid rocket boosters for launch. Liftoff is targeted for Nov. 1.

At NASA's Johnson Space Center, the STS-133 astronauts will practice flight procedures in their T-38 training aircraft and perform various administrative duties.