Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Why space dust emits radio waves upon crashing into a spacecraft

04.05.2017

A new simulation provides the first mechanism to explain why plasma from hypervelocity impacts generates electromagnetic radiation

When spacecraft and satellites travel through space they encounter tiny, fast moving particles of space dust and debris. If the particle travels fast enough, its impact appears to create electromagnetic radiation (in the form of radio waves) that can damage or even disable the craft's electronic systems.


The high-velocity impact of a piece of dust or orbital debris generates plasma and an associated Radio Frequency emission.

Credit: Fletcher/Close

A new study published this week in the journal Physics of Plasmas, from AIP Publishing, uses computer simulations to show that the cloud of plasma generated from the particle's impact is responsible for creating the damaging electromagnetic pulse. They show that as the plasma expands into the surrounding vacuum, the ions and electrons travel at different speeds and separate in a way that creates radio frequency emissions.

"For the last few decades researchers have studied these hypervelocity impacts and we've noticed that there's radiation from the impacts when the particles are going sufficiently fast," said lead author Alex Fletcher, now a postdoctoral researcher at the Boston University Center for Space Physics. "No one has really been able to explain why it's there, where it comes from or the physical mechanism behind it."

The study is a step towards verifying the theory of senior author Sigrid Close, associate professor of aeronautics and astronautics at Stanford University. In 2010, Close and colleagues published the initial hypothesis that hypervelocity impact plasmas are responsible for a few satellite failures.

To simulate the results from a hypervelocity impact plasma, researchers used a method called particle-in-cell simulation that allows them to model the plasma and the electromagnetic fields simultaneously. They fed the simulation details from a previously developed hydrocode -- a computational tool they used to model the fluid and solid dynamics of the impact. The researchers let the simulation evolve and calculated the radiation produced by the plasma.

When a particle hits a hard surface at high speeds, it vaporizes and ionizes the target, releasing a cloud of dust, gas and plasma. As the plasma expands into the surrounding vacuum (of space), its density drops and it enters a collisionless state where its particles no longer interact directly with one another.

In the current study, the researchers make the assumption that the electrons in this collisionless plasma then travel faster than the larger ions. Their simulation predicts that this large-scale charge separation generates the radiation. The model's results are consistent with Close's initial theory, but predict a higher frequency for the emission than researchers have detected experimentally.

The authors point out that the assumption that the electrons move en masse as they separate from the ions deserves more careful attention. The group is building new simulations to test whether the shift to a collisionless state is sufficient to create the separation.

Fletcher also notes that they have neglected to account for the dust.

"The impact creates dust particles that interact with the plasma," Fletcher said. The dynamics of these "dusty plasmas" are an area for future research.

The next step in the work is to use the simulation to quantify the radiation generated so they can assess the threat to satellites, and devise ways to protect satellites and spacecraft from meteoroids and orbital debris.

"More than half of electrical failures are unexplained because it's very hard to do diagnostics on a satellite that fails in orbit," Fletcher said. "We believe we can attribute some of these failures to this mechanism."

###

The article, "Particle-in-cell simulations of an RF emission mechanism associated with hypervelocity impact plasmas," is authored by Alex Fletcher and Sigrid Close. The article appears in Physics of Plasmas May 2, 2017 (DOI: 10.1063/1.4980833). After that date, it can be accessed http://aip.scitation.org/doi/full/10.1063/1.4980833.

ABOUT THE JOURNAL

Physics of Plasmas is devoted to the publication of original experimental and theoretical work in plasma physics, from basic plasma phenomena to astrophysical and dusty plasmas. See http://pop.aip.org.

Media Contact

Julia Majors
media@aip.org
301-209-3090

 @jasonbardi

http://www.aip.org

Julia Majors | EurekAlert!

Further reports about: radio waves satellite satellites space dust spacecraft vacuum

More articles from Physics and Astronomy:

nachricht NASA detects solar flare pulses at Sun and Earth
17.11.2017 | NASA/Goddard Space Flight Center

nachricht Pluto's hydrocarbon haze keeps dwarf planet colder than expected
16.11.2017 | University of California - Santa Cruz

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: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>