David Kirkpatrick

October 18, 2009

IBEX finds solar system surprise

This release is from Friday and I’ve read this news a few different places and caught several releases, but this one is pretty comprehensive and contains a multitude of citations and external links.

Surprises in any scientific research are interesting, and often they are pretty cool.

The release:

Satellite reveals surprising cosmic ‘weather’ at edge of solar system

IMAGE: Priscilla Frisch, Senior Scientist in Astronomy & Astrophysics, and member of the science team, Interstellar Boundary Explorer. Collaborating with former UChicago astronomer Thomas F. Adams, she made the first spectrum…

Click here for more information.

The first solar system energetic particle maps show an unexpected landmark occurring at the outer edge of the solar wind bubble surrounding the solar system. Scientists published these maps, based mostly on data collected from NASA’s Interstellar Boundary Explorer satellite, in the Oct. 15 issue of Science Express, the advance online version of the journal Science.

“Nature is full of surprises, and IBEX has been lucky to discover one of those surprises,” said Priscilla Frisch, a senior scientist in astronomy & astrophysics at the University of Chicago. “The sky maps are dominated by a giant ribbon of energetic neutral atoms extending throughout the sky in an arc that is 300 degrees long.” Energetic neutral atoms form when hot solar wind ions (charged particles) steal electrons from cool interstellar neutral atoms.

IBEX was launched Oct. 19, 2008, to produce the first all-sky maps of the heliosphere, which reaches far beyond the solar system’s most distant planets. Extending more than 100 times farther than the distance from Earth to the sun, the heliosphere marks the region of outer space subjected to the sun’s particle emissions.

The new maps show how high-speed cosmic particle streams collide and mix at the edge of the heliosphere, said Frisch, who co-authored three of a set of IBEX articles appearing in this week’s Science Express. The outgoing solar wind blows at 900,000 miles an hour, crashing into a 60,000-mile-an-hour “breeze” of incoming interstellar gas.

Revealed in the IBEX data, but not predicted in the theoretical heliosphere simulations of three different research groups, was the ribbon itself, formed where the direction of the interstellar magnetic field draping over the heliosphere is perpendicular to the viewpoint of the sun.

IMAGE: Image from one of the IBEX papers published in the Oct. 16, 2009, issue of Science showing a map of the ribbon of energetic neutral atoms (in green and yellow)…

Click here for more information.

Energetic protons create forces as they move through the magnetic field, and when the protons are bathed in interstellar neutrals, they produce energetic neutral atoms. “We’re still trying to understand this unexpected structure, and we believe that the interstellar magnetic forces are associated with the enhanced ENA production at the ribbon,” Frisch said.

IBEX shows that energetic neutral atoms are produced toward the north pole of the ecliptic (the plane traced by the orbit of the planets around the sun), as well as toward the heliosphere tail pointed toward the constellations of Taurus and Orion. “The particle energies change between the poles and tail, but surprisingly not in the ribbon compared to adjacent locations,” Frisch said.

###

BEX is the latest in NASA’s series of low-cost, rapidly developed Small Explorers space missions. Southwest Research Institute in San Antonio, Texas, leads and developed the mission with a team 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.

Citations: N. A. Schwadron, M. Bzowski, G. B. Crew, M. Gruntman, H. Fahr, H. Fichtner, P. C. Frisch, H. O. Funsten, S. Fuselier, J. Heerikhuisen, V. Izmodenov, H. Kucharek, M. Lee, G. Livadiotis, D. J. McComas, E. Moebius, T. Moore, J. Mukherjee, N.V. Pogorelov, C. Prested, D. Reisenfeld, E. Roelof, G.P. Zank, “Comparison of Interstellar Boundary Explorer Observations with 3-D Global Heliospheric Models,” ScienceExpress, Oct. 15, 2009.

H.O. Funsten, F. Allegrini, G.B. Crew, R. DeMajistre, P.C. Frisch, S.A. Fuselier, M. Gruntman, P. Janzen, D.J. McComas, E. Möbius, B. Randol, D.B. Reisenfeld, E.C. Roelof, N.A. Schwadron, “Structures and Spectral Variations of the Outer Heliosphere in IBEX Energetic Neutral Atom Maps,”Science Express, Oct. 15, 2009.

D.J. McComas, F. Allegrini1, P. Bochsler, M. Bzowski, E.R. Christian, G.B.Crew, R. DeMajistre, H. Fahr, H. Fichtner, P.C. Frisch, H.O. Funsten, S. A. Fuselier, G. Gloeckler, M. Gruntman, J. Heerikhuisen, V. Izmodenov, P.J anzen, P. Knappenberger, S. Krimigis, H. Kucharek, M. Lee, G. Livadiotis, S. Livi, R.J. MacDowall, D. Mitchell, E. Möbius, T. Moore, N.V. Pogorelov, D. Reisenfeld, E. Roelof, L. Saul, N.A. Schwadron, P.W. Valek, R. Vanderspek, P. Wurz, G.P. Zank, “Global Observations of the Interstellar Interaction from the Interstellar Boundary Explorer-IBEX”, ScienceExpress, Oct. 15, 2009.

Related links:

Animation shows how energetic neutral atoms are made in the heliosheath when hot solar wind protons grab an electron from a cold interstellar gas atom. The ENAs can then easily travel back into the solar system, where some are collected by IBEX. Credit: NASA/GSFChttp://www.swri.org/temp/ibexscience/DM/SP_draft1.mov

Solar Journey: The Significant of Our Galactic Environment for the Heliosphere and Earth, Priscilla C. Frisch, editor.http://www.springer.com/astronomy/practical+astronomy/book/978-1-4020-4397-0

IBEX Web page at Southwest Research Institute http://ibex.swri.edu/

NASA’s Interstellar Boundary Explorer mission http://www.nasa.gov/mission_pages/ibex/index.html

To view a video related to this research, please visit http://astro.uchicago.edu/%7Efrisch/soljourn/Hanson/AstroBioScene7Sound.mov

If you’re dying for more on the topic, here’s another press release.

October 15, 2008

NASA and the weakening solar bubble

Filed under: Media, Science, Technology — Tags: , , , , — David Kirkpatrick @ 1:15 pm

Here’s a discussion on an odd and a little unsettling topic. Probabaly just part of usual long-term fluctuations, but we may feel some effects in the meantime. I’ve blogged on the IBEX project before here.

The release:

NASA to Discuss Mission to Study Sun’s Weakening Protective Bubble

GREENBELT, Md., Oct. 15 /PRNewswire-USNewswire/ — NASA will hold a media teleconference on Friday, Oct. 17, at 1 p.m. EDT, to preview the Interstellar Boundary Explorer, or IBEX, mission. The spacecraft may confirm if the sun’s protective bubble surrounding our solar system, called the heliosphere, is about to shrink and weaken. IBEX also will be the first spacecraft to image and map the dynamic interactions taking place where the hot solar wind slams into the cold expanse of space.

(LOGO:  http://www.newscom.com/cgi-bin/prnh/20081007/38461LOGO )

The heliosphere acts as a shield for our solar system, warding off most of the galactic cosmic rays. Recent data indicate the solar wind’s global pressure is the lowest seen since the beginning of the space age.

IBEX is set to launch Oct. 19 from the Kwajalein Atoll, a part of the Marshall Islands in the Pacific Ocean.

Panelists will be:

– David McComas, IBEX principal investigator at Southwest Research Institute in San Antonio

– Nathan Schwadron, co-investigator and IBEX Science Operations Center lead at Boston University

– Stephen Fuselier, co-investigator and IBEX-Lo Sensor lead at Lockheed-Martin Advanced Technology Center in Palo Alto, Calif.

– Eric Christian, program scientist at NASA Headquarters in Washington

Photo:  http://www.newscom.com/cgi-bin/prnh/20081007/38461LOGO
AP Archive:  http://photoarchive.ap.org/
PRN Photo Desk photodesk@prnewswire.com
Source: NASA
   
Web Site:  http://www.nasa.gov/

September 23, 2008

Solar wind at 50-year low

Filed under: Science — Tags: , , , , , — David Kirkpatrick @ 1:31 pm

This sounds a bit disturbing to me.

The NASA release:

Ulysses Reveals Global Solar Wind Plasma Output at 50-Year Low

WASHINGTON, Sept. 23 /PRNewswire-USNewswire/ — Data from the Ulysses spacecraft, a joint NASA-European Space Agency mission, show the sun has reduced its output of solar wind to the lowest levels since accurate readings became available. The sun’s current state could reduce the natural shielding that envelops our solar system.

“The sun’s million mile-per-hour solar wind inflates a protective bubble, or heliosphere, around the solar system. It influences how things work here on Earth and even out at the boundary of our solar system where it meets the galaxy,” said Dave McComas, Ulysses’ solar wind instrument principal investigator and senior executive director at the Southwest Research Institute in San Antonio. “Ulysses data indicate the solar wind’s global pressure is the lowest we have seen since the beginning of the space age.”

The sun’s solar wind plasma is a stream of charged particles ejected from the sun’s upper atmosphere. The solar wind interacts with every planet in our solar system. It also defines the border between our solar system and interstellar space.

This border, called the heliopause, surrounds our solar system where the solar wind’s strength is no longer great enough to push back the wind of other stars. The region around the heliopause also acts as a shield for our solar system, warding off a significant portion of the cosmic rays outside the galaxy.

“Galactic cosmic rays carry with them radiation from other parts of our galaxy,” said Ed Smith, NASA’s Ulysses project scientist at the Jet Propulsion Laboratory in Pasadena, Calif. “With the solar wind at an all-time low, there is an excellent chance the heliosphere will diminish in size and strength. If that occurs, more galactic cosmic rays will make it into the inner part of our solar system.”

Galactic cosmic rays are of great interest to NASA. Cosmic rays are linked to engineering decisions for unmanned interplanetary spacecraft and exposure limits for astronauts traveling beyond low-Earth orbit.

In 2007, Ulysses made its third rapid scan of the solar wind and magnetic field from the sun’s south to north pole. When the results were compared with observations from the previous solar cycle, the strength of the solar wind pressure and the magnetic field embedded in the solar wind were found to have decreased by 20 percent. The field strength near the spacecraft has decreased by 36 percent.

“The sun cycles between periods of great activity and lesser activity,” Smith said. “Right now, we are in a period of minimal activity that has stretched on longer than anyone anticipated.”

Ulysses was the first mission to survey the space environment over the sun’s poles. Data Ulysses has returned have forever changed the way scientists view our star and its effects. The venerable spacecraft has lasted more than 18 years, or almost four times its expected mission lifetime. The Ulysses solar wind findings were published in a recent edition of Geophysical Research Letters.

The Ulysses spacecraft was carried into Earth orbit aboard space shuttle Discovery on Oct. 6, 1990. From Earth orbit it was propelled toward Jupiter, passing the planet on Feb. 8, 1992. Jupiter’s immense gravity bent the spacecraft’s flight path downward and away from the plane of the planets’ orbits. This placed Ulysses into a final orbit around the sun that would take it over its north and south poles.

The Ulysses spacecraft was provided by ESA, having been built by Astrium GmbH (formerly Dornier Systems) of Friedrichshafen, Germany. NASA provided the launch vehicle and the upper stage boosters. The U.S. Department of Energy supplied a radioisotope thermoelectric generator to power the spacecraft. Science instruments were provided by U.S. and European investigators. The spacecraft is operated from JPL by a joint NASA-ESA team.

More information about the Ulysses mission is available on the Web at:

http://ulysses.jpl.nasa.gov/.

Source: NASA
   

Web Site:  http://www.nasa.gov/