Chandra looks back at the Earth
In an unusual observation, a team of scientists has scanned the northern polar region of Earth with NASA’s Chandra X-ray Observatory. The results show that the aurora borealis, or "northern lights," also dance in X-ray light, creating changing bright arcs of X-ray energy above the Earth’s surface.
While other satellite observations had previously detected high-energy X-rays from the Earth auroras, the latest Chandra observations reveal low-energy X-rays generated for the first time during auroral activity.
The researchers, led by Dr. Ron Elsner of NASA’s Marshall Space Flight Center in Huntsville, Ala., used Chandra to observe the Earth 10 times over a four-month period in 2004. The images were created from approximately 20-minute scans during which Chandra was aimed at a fixed point in the sky and the Earth’s motion carried the auroral regions through Chandra’s field of view.
From the ground, the aurora are known to change dramatically over time, and this is also the case in X-ray light. The X-rays in this sample of the Chandra observations, which have been superimposed on an approximate representation of the Earth, are seen here.
Auroras are produced by solar storms that eject clouds of energetic charged particles. These particles are deflected when they encounter the Earth’s magnetic field, but in the process large electric voltages are created. Electrons trapped in the Earth’s magnetic field are accelerated by these voltages and spiral along the magnetic field into the polar regions. There they collide with atoms high in the atmosphere and emit X-rays. Chandra has also observed dramatic auroral activity on Jupiter.
Dr. Anil Bhardwaj is the lead author on a paper describing these results in the Journal of Atmospheric and Solar-Terrestrial Physics. Dr. Bhardwaj was a co-investigator on this project and worked with Dr. Elsner at NASA’s Marshall Space Flight Center while this research was conducted.
The research team also includes Randy Gladstone, Southwest Research Institute, San Antonio, Texas; Nikolai Østgaard, University of Bergen, Norway; Hunter Waite and Tariq Majeed, University of Michigan, Ann Arbor; Thomas Cravens, University of Kansas, Lawrence; Shen-Wu Chang, University of Alabama, Huntsville; and Albert E. Metzger, Jet Propulsion Laboratory, Pasadena, Calif.
Megan Watzke | EurekAlert!
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.
This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...
Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion
Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...