Spaceflight Now Home



Spaceflight Now +



Premium video content for our Spaceflight Now Plus subscribers.

NASA budget hearing
This U.S. Senate space subcommittee hearing to examine NASA's proposed Fiscal Year 2008 budget features testimony from NASA Administrator Mike Griffin on February 28.

 Part 1 | Part 2

Hail delays Atlantis
Launch of space shuttle Atlantis is postponed after golf ball-sized hail from a severe storm damaged the foam insulation on the external fuel tank. NASA announces the delay and plans to return the shuttle to the Vehicle Assembly Building for repairs.

 Play

STS-116: ISS re-wiring
Spacewalking astronauts on the December 2006 flight of shuttle Discovery performed a delicate re-wiring of the International Space Station's electrical system and retracted a stubborn solar array wing. The work accomplished critical steps in preparing the station to power the upcoming international science laboratory modules. Some members of the STS-116 crew narrate the highlights of the mission in this post-flight film.

 Play

STS-111: ISS arm gets new mobility
Shuttle Endeavour's visit to the space station in June 2002 brought up the Expedition 5 long-duration resident crew, a load of supplies and the Mobile Base System to serve as the platform for moving the station's robotic arm up and down the truss backbone. The shuttle crew also performed some surgery on the robot arm by replacing a failed joint. The crew narrates the highlights of STS-111 in this post-flight film.

 Play

Delta 2 launches THEMIS
The United Launch Alliance Delta 2 rocket roared away from Cape Canaveral Saturday carrying a quintet of NASA probes that seek to understand the physics behind auroral displays.

 Full Coverage

STS-117: Astronauts meet the press
The STS-117 astronauts meet the press during the traditional pre-flight news conference held at the Johnson Space Center a month prior to launch. The six-person crew will deliver and activate a solar-power module for the International Space Station.

 Play

Atlantis rolls to pad
After a six-hour trip along the three-and-a-half-mile crawlerway from the Vehicle Assembly Building, space shuttle Atlantis arrives at launch pad 39A for the STS-117 mission.

 Roll starts | Pad arrival

Atlantis rollover
Space shuttle Atlantis emerges from its processing hangar at dawn February 7 for the short trip to the Vehicle Assembly Building at Kennedy Space Center's Complex 39.

 Leaving hangar | To VAB

Time-lapse movies:
 Pulling in | Sling

Technical look at
Project Mercury

This documentary takes a look at the technical aspects of Project Mercury, including development of the capsule and the pioneering first manned flights of America's space program.

 Play

Apollo 15: In the Mountains of the Moon
The voyage of Apollo 15 took man to the Hadley Rille area of the moon. Astronauts Dave Scott and Jim Irwin explored the region using a lunar rover, while Al Worden remained in orbit conducting observations. "Apollo 15: In the Mountains of the Moon" is a NASA film looking back at the 1971 flight.

 Play

Skylab's first 40 days
Skylab, America's first space station, began with crippling problems created by an incident during its May 1973 launch. High temperatures and low power conditions aboard the orbital workshop forced engineers to devise corrective measures quickly. Astronauts Pete Conrad, Paul Weitz and Joe Kerwin flew to the station and implemented the repairs, rescuing the spacecraft's mission. This film tells the story of Skylab's first 40 days in space.

 Play

Become a subscriber
More video



Sensor being developed to check for life on Mars
EUROPEAN SPACE AGENCY NEWS RELEASE
Posted: February 28, 2007

NASA-funded researchers are refining a tool that could not only check for the faintest traces of life's molecular building blocks on Mars, but could also determine whether they have been produced by anything alive.


Artist's concept of ExoMars. Credit: European Space Agency
 
The instrument, called Urey: Mars Organic and Oxidant Detector, has already shown its capabilities in one of the most barren climes on Earth, the Atacama Desert in Chile. The European Space Agency has chosen this tool from the United States as part of the science payload for the ExoMars rover planned for launch in 2013. Last month, NASA selected Urey for an instrument-development investment of $750,000.

The European Space Agency plans for the ExoMars rover to grind samples of Martian soil to fine powder and deliver them to a suite of analytical instruments, including Urey, that will search for signs of life. Each sample will be a spoonful of material dug from underground by a robotic drill.

"Urey will be able to detect key molecules associated with life at a sensitivity roughly a million times greater than previous instrumentation," said Dr. Jeffrey Bada of Scripps Institution of Oceanography at the University of California, San Diego. Bada is the principal investigator for an international team of scientists and engineers working on various components of the device.

To aid in interpreting that information, part of the tool would assess how rapidly the environmental conditions on Mars erase those molecular clues.

Dr. Pascale Ehrenfreund of the University of Leiden in the Netherlands, said, "The main objective of ExoMars is to search for life. Urey will be a key instrument for that because it is the one with the highest sensitivity for organic chemicals." Ehrenfreund, one of two deputy principal investigators for Urey, coordinates efforts of team members from five other European countries.

Urey can detect several types of organic molecules, such as amino acids, at concentrations as low as a few parts per trillion.

All life on Earth assembles chains of amino acids to make proteins. However, amino acids can be made either by a living organism or by non-biological means. This means it is possible that Mars has amino acids and other chemical precursors of life but has never had life. To distinguish between that situation and evidence for past or present life on Mars, the Urey instrument team will make use of the knowledge that most types of amino acids can exist in two different forms. One form is referred to as "left-handed" and the other as "right-handed." Just as the right hand on a human mirrors the left, these two forms of an amino acid mirror each other.

Amino acids from a non-biological source come in a roughly 50-50 mix of right-handed and left-handed forms. Life on Earth, from the simplest microbes to the largest plants and animals, makes and uses only left-handed amino acids, with rare exceptions. Comparable uniformity -- either all left or all right -- is expected in any extraterrestrial life using building blocks that have mirror-image versions because a mixture would complicate biochemistry.

"The Urey instrument will be able to distinguish between left-handed amino acids and right-handed ones," said Allen Farrington, Urey project manager at NASA's Jet Propulsion Laboratory, which will build the instrument to be sent to Mars.

If Urey were to find an even mix of the mirror-image molecules on Mars, that would suggest life as we know it never began there. All-left or all-right would be strong evidence that life now exists on Mars, with all-right dramatically implying an origin separate from Earth life. Something between 50-50 and uniformity could result if Martian life once existed, because amino acids created biologically gradually change toward an even mixture in the absence of life.

The 1976 NASA Viking mission discovered that strongly oxidizing conditions at the Martian surface complicate experiments to search for life. The Urey instrument has a component, called the Mars oxidant instrument, for examining those conditions.

The oxidant instrument has microsensors coated with various chemical films. "By measuring the reaction of the sensor films with chemicals present in the Martian soil and atmosphere, we can establish if organisms could survive and if evidence of past life would be preserved," said Dr. Richard Quinn, a co-investigator on Urey from the SETI Institute, Mountain View, Calif., who also works at NASA Ames Research Center, Moffett Field, Calif.

"In order to improve our chances of finding chemical evidence of life on Mars, and designing human habitats and other equipment that will function well on Mars' surface, we need to improve our understanding of oxidants in the planet's surface environment," said Dr. Aaron Zent, a Urey co-investigator at NASA Ames.

A Urey component called the sub-critical water extractor handles the task of getting any organic compounds out of each powdered sample the ExoMars rover delivers to the instrument. "It's like an espresso maker," explained JPL's Dr. Frank Grunthaner, a deputy principal investigator for Urey. "We bring the water with us. It is added to the sample, and different types of organic compounds dissolve into the liquid as the temperature increases. We keep it under pressure the whole time."

The dissolved compounds are highly concentrated by stripping away water in a tiny oven.

Then a detector checks for fluorescent glowing, which would indicate the presence of amino acids, some components of DNA and RNA, or other organic compounds that bind to a fluorescing chemical added by the instrument.

A Urey component called the micro-capillary electrophoresis unit has the critical job of separating different types of organic compounds from one another for identification, including separation of mirror-image amino acids from each other. "We have essentially put a laboratory onto a single wafer," said Dr. Richard Mathies of the University of California, Berkeley, a Urey co-investigator. The device for sending to Mars will be a small version incorporating this detection technology, which is already in use for biomedical procedures such as law-enforcement DNA tests and checking for hazardous microbes.

Switzerland will provide electronics design and packaging expertise for Urey. Micro-Cameras and Space Exploration S.A., Neuchatel, will collaborate with JPL and the European Space Agency to accomplish this significant contribution to the heart of the instrument. Dr. Jean-Luc Josset, Urey co-investigator at the University of Neuchatel will coordinate this effort and help provide detector selection and support. JPL is a division of the California Institute of Technology in Pasadena.

Final Shuttle Mission Patch

Free shipping to U.S. addresses!

The crew emblem for the final space shuttle mission is now available in our store. Get this piece of history!
 U.S. STORE
 WORLDWIDE STORE

STS-134 Patch

Free shipping to U.S. addresses!

The final planned flight of space shuttle Endeavour is symbolized in the official embroidered crew patch for STS-134. Available in our store!
 U.S. STORE
 WORLDWIDE STORE

Ares 1-X Patch
The official embroidered patch for the Ares 1-X rocket test flight, is available for purchase.
 U.S. STORE
 WORLDWIDE STORE

Apollo Collage
This beautiful one piece set features the Apollo program emblem surrounded by the individual mission logos.
 U.S. STORE
 WORLDWIDE STORE

Project Orion
The Orion crew exploration vehicle is NASA's first new human spacecraft developed since the space shuttle a quarter-century earlier. The capsule is one of the key elements of returning astronauts to the Moon.
 U.S. STORE


Fallen Heroes Patch Collection
The official patches from Apollo 1, the shuttle Challenger and Columbia crews are available in the store.
 U.S. STORE
 WORLDWIDE STORE


Ares 1-X Patch
The official embroidered patch for the Ares 1-X rocket test flight, is available for purchase.
 U.S. STORE
 WORLDWIDE STORE

Apollo Collage
This beautiful one piece set features the Apollo program emblem surrounded by the individual mission logos.
 U.S. STORE

Expedition 21
The official embroidered patch for the International Space Station Expedition 21 crew is now available from our stores.
 U.S. STORE
 WORLDWIDE STORE

Hubble Patch
The official embroidered patch for mission STS-125, the space shuttle's last planned service call to the Hubble Space Telescope, is available for purchase.
 U.S. STORE
 WORLDWIDE STORE

INDEX | PLUS | NEWS ARCHIVE | LAUNCH SCHEDULE
ASTRONOMY NOW | STORE

ADVERTISE

© 2014 Spaceflight Now Inc.