Blazar Variability

An artist’s conception of a blazar, a galay powered by an active nucleus. Blazars are the most common sources detected by NASA’s Fermi gamma-ray spacecraft. Astronomers have modeled the bright, variable emission from the blazar CTA102 between 2013-2017 using data taken from the gamma-ray to radio bands. They are able to explain the multiuwavelegnth variability observed using a geometrical model for the rapidly moving jets. Credit: M. Weiss/CfA

Active galactic nuclei (AGN) are supermassive black holes at the centers of galaxies that are accreting material. These AGN emit jets of charged particles that move at speeds close to that of light, transporting huge amounts of energy away from the central black hole region and radiating across the electromagnetic spectrum...

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Paving the way for Spintronic RAMs: A deeper look into a powerful spin phenomenon

Figure 1. An extremely simple MRAM
An extremely simple MRAM

The proposed combination of materials serves as a memory unit by supporting read and write operations. The spin injection by the topological insulator (TI) material reverses the magnetization of the ferromagnetic (FM) material, representing the “write” operation. Furthermore, the spin injection can also change the overall resistance of the materials, which can be sensed through an external circuit, representing the “read” operation.

Scientists at Tokyo Institute of Technology (Tokyo Tech) explore a new material combination that sets the stage for magnetic random access memories, which rely on spin – an intrinsic property of electrons – and could outperform current storage devices...

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Learning from the Bears

Grizzly bears’ muscles manage to survive hibernation virtually unharmed. Researchers are trying to understand the mechanisms behind this ability in order to help bedridden patients.
© Gotthardt Lab, MDC

Grizzly bears spend many months in hibernation, but their muscles do not suffer from the lack of movement. In the journal Scientific Reports, a team led by Michael Gotthardt reports on how they manage to do this. The grizzly bears’ strategy could help prevent muscle atrophy in humans as well.

A grizzly bear only knows three seasons during the year. Its time of activity starts between March and May. Around September the bear begins to eat large quantities of food. And sometime between November and January, it falls into hibernation...

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Giant Magnetic Ropes seen in Whale Galaxy’s Halo

Composite image of galaxy NGC 4631, the
Composite image of the galaxy NGC 4631, the “Whale Galaxy,” revealing large magnetic structures.
Credit: Composite image by Jayanne English of the University of Manitoba, with NRAO VLA radio data from Silvia Carolina Mora-Partiarroyo and Marita Krause of the Max-Planck Institute for Radio Astronomy

Using the National Science Foundation’s Karl G. Jansky Very Large Array radio telescope, a team of astronomers has captured for the first time an image of large-scale, coherent, magnetic fields in the halo of a faraway spiral galaxy, confirming theoretical modeling of how galaxies generate magnetic fields and potentially increasing knowledge of how galaxies form and evolve.

The international consortium, led by scientists from the Max Planck Institute for Radio Astronomy in Bonn, Germany, and...

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