Interstellar atoms flow past the Earth as the solar system passes through the surrounding interstellar cloud at 23 kilometers per second (50,000 miles per hour).
The latest IBEX measurements of the interstellar wind direction were discovered to differ from those made by the Ulysses spacecraft in the 1990s. That difference led the IBEX team to compare the IBEX measurements to data gathered by 11 spacecraft between 1972 and 2011.
Statistical testing of the Earth-orbiting and interplanetary spacecraft data showed that, over the past 40 years, the longitude of the interstellar helium wind has changed by 6.8 ± 2.4 degrees.
"We concluded it's highly likely that the direction of the interstellar wind has changed over the past 40 years. It's also highly unlikely that the direction of the interstellar helium wind has remained constant," says Dr. Priscilla Frisch, lead author of the study and a senior scientist in the Department of Astronomy and Astrophysics at the University of Chicago.
"We think the change in wind direction could be explained by turbulence in the interstellar cloud around the Sun," she says.
The spacecraft data used for this study were gathered using three methods to measure the neutral interstellar helium wind direction: IBEX and Ulysses provided direct in situ measurements of the neutral wind; the earliest measurements from the 1970s used fluorescence of solar extreme ultraviolet radiation of the helium atoms near the Sun; and measurements also were included of the helium flow direction from "pickup ions," neutral particles in the solar system that become ionized near the Sun and join the solar wind.
"This result is really stunning," says Dr. Dave McComas, IBEX principal investigator, assistant vice president of the Space Science and Engineering Division at Southwest Research Institute, and an author on the paper. "Previously we thought the very local interstellar medium was very constant, but these results show just how dynamic the solar system’s interaction is."
The paper, "Decades-long Changes of the Interstellar Wind Through our Solar System," by P.C. Frisch, M. Bzowski, G., Livadiotis, D.J. McComas, E. Moebius, H.-R. Mueller, W.R. Pryor, N.A. Schwadron, J.M. Sokol, J.V. Vallerga and J.M. Ajello, was published today in the journal Science.
IBEX is one of NASA's series of low-cost, rapidly developed Small Explorer space missions. Southwest Research Institute in San Antonio leads the IBEX mission with teams of national and international partners. NASA's Goddard Space Flight Center in Greenbelt, Md., manages the Explorers Program for NASA's Science Mission Directorate in Washington.
For more information, contact Maria Martinez at (210) 522-3305, Communications Department, PO Drawer 28510, San Antonio, TX 78228-0510.
Maria Martinez | EurekAlert!
Quantum optics allows us to abandon expensive lasers in spectroscopy
22.11.2017 | Lomonosov Moscow State University
Nano-watch has steady hands
22.11.2017 | University of Vienna
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
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...
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...
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....
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,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
22.11.2017 | Business and Finance
22.11.2017 | Physics and Astronomy
22.11.2017 | Physics and Astronomy