Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cosmic rays threaten future deep-space astronaut missions

22.10.2014

Crewed missions to Mars remain an essential goal for NASA, but scientists are only now beginning to understand and characterize the radiation hazards that could make such ventures risky, concludes a new paper by University of New Hampshire scientists.

In a paper published online in the journal Space Weather, associate professor Nathan Schwadron of the UNH Institute for the Study of Earth, Oceans, and Space (EOS) and the department of physics says that due to a highly abnormal and extended lack of solar activity, the solar wind is exhibiting extremely low densities and magnetic field strengths, which causes dangerous levels of hazardous radiation to pervade the space environment.

"The behavior of the sun has recently changed and is now in a state not observed for almost 100 years," says Schwadron, lead author of the paper and principal investigator for the Cosmic Ray Telescope for
the Effects of Radiation (CRaTER) on NASA's Lunar Reconnaissance Orbiter (LRO). He notes that throughout most of the space age, the sun's activity has shown a clockwork 11-year cycle, with approximately six- to eight-year lulls in activity (solar minimum) followed by two- to three-year periods when the sun is more active. "However, starting in about 2006, we observed the longest solar minimum and weakest solar activity observed in the space age."

These conditions brought about the highest intensities of galactic cosmic rays seen since the beginning of the space age, which have created worsening radiation hazards that potentially threaten future deep-space astronaut missions.

"While these conditions are not necessarily a showstopper for long-duration missions to the moon, an asteroid, or even Mars, galactic cosmic ray radiation in particular remains a significant and worsening factor that limits mission durations," says Schwadron.

The study is the capstone article in the Space Weather CRaTER Special Issue, which provides comprehensive findings on space-based radiation as measured by the UNH-led detector. The data provide critical information on the radiation hazards that will be faced by astronauts on extended missions to deep space such as those to Mars. The papers can be viewed here: http://onlinelibrary.wiley.com/10.1002/(ISSN)1542-7390/specialsection/CRATER1

"These data are a fundamental reference for the radiation hazards in near Earth 'geospace' out to Mars and other regions of our sun's vast heliosphere," says Schwadron.

At the heart of CRaTER is material called "tissue equivalent plastic"—a stand-in for human muscle capable of gauging radiation dosage. Ionizing radiation from galactic cosmic rays and solar energetic particles remains a significant challenge to long-duration crewed missions to deep space. Human beings face a variety of consequences ranging from acute effects (radiation sickness) to long-term effects including cancer induction and damage to organs including the heart and brain.

The high radiation levels seen during the sun's last minimum cycle limits the allowable days for typical astronauts behind spacecraft shielding. Given the trend of reducing solar output, the allowable days in space for astronauts is dropping and estimated to be 20 percent lower in the coming solar minimum cycle as compared to the last minimum cycle.

UNH coauthors on the capstone paper titled "Does the worsening radiation environment preclude future manned deep-space exploration?" include Colin Joyce, Marty Quinn, Charles Smith, Sonya Smith, Harlan Spence, and Jody Wilson.

###

The CRaTER investigation is a collaboration with team members at UNH, the University of Tennessee at Knoxville, Southwest Research Institute, Harvard-Smithsonian Center for Astrophysics, The Aerospace Corporation, the University of Michigan, and NASA Goddard Spaceflight Center. For more information on the CRaTER instrument and the LRO mission, visit http://crater.unh.edu.

Support for this research comes from NASA's LRO/CRaTER mission, and NASA'S Earth-Moon-Mars Radiation Environment Module and Corona-Solar Wind Energetic Particle Acceleration projects. Additional support is provided by the National Science Foundation's Frontiers in Earth-System Dynamics program, which funds the UNH-led "Sun-to-Ice" project that uses theory and modeling results to inform the analysis of current space-based NASA measurements of the radiation environment.

The NASA Goddard Space Flight Center in Greenbelt, Md. developed and manages the LRO mission. LRO's current science mission is implemented for NASA's Science Mission Directorate. NASA's Exploration Systems Mission Directorate sponsored LRO's initial one-year exploration mission that concluded in September 2010.

The University of New Hampshire, founded in 1866, is a world-class public research university with the feel of a New England liberal arts college. A land, sea, and space-grant university, UNH is the state's flagship public institution, enrolling 12,300 undergraduate and 2,200 graduate students.

Images to download: http://www.eos.unh.edu/Spheres_1012/graphics/fall12_pics/prediccs2_lg.jpg

Caption: Solar flare observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager and associated coronal mass ejection observed by the Solar and Heliospheric Observatory spacecraft. Solar energetic particles from these events can easily penetrate typical shielding and damage spacecraft electronics and biological cells. Image courtesy of Nathan Schwadron, UNH-EOS.

http://www.eos.unh.edu/Spheres_0312/graphics/spr12_pics/lro_lg.jpg

Caption: Artist's rendition of the Lunar Reconnaissance Orbiter at the moon. The CRaTER telescope is seen pointing out at the bottom right center of the LRO spacecraft. Illustration by Chris Meaney/NASA.

David Sims | Eurek Alert!

More articles from Physics and Astronomy:

nachricht Electrocatalysis can advance green transition
23.01.2017 | Technical University of Denmark

nachricht Quantum optical sensor for the first time tested in space – with a laser system from Berlin
23.01.2017 | Ferdinand-Braun-Institut Leibniz-Institut für Höchstfrequenztechnik

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Tracking movement of immune cells identifies key first steps in inflammatory arthritis

23.01.2017 | Health and Medicine

Electrocatalysis can advance green transition

23.01.2017 | Physics and Astronomy

New technology for mass-production of complex molded composite components

23.01.2017 | Process Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>