Category Astronomy/Space

High-Flying Experiments Demonstrate Potential of Balloon-Borne Infrasound Detection

Experiments conducted high in the skies over New Mexico suggest that balloon-borne sensors could be useful in detecting the infrasound signals generated by small, extraterrestrial debris entering Earth’s atmosphere, according to a report at the 2017 Seismological Society of America’s (SSA) Annual Meeting. Infrasound, sometimes called low-frequency sound, is sound waves that occur at frequencies lower than the limit of human hearing. Infrasound signals can remain strong as they travel over large distances, making them useful for pinpointing the location and size of events such as nuclear explosions, meteorite strikes, volcanic eruptions and sometimes earthquake ruptures.

Ground sensors can detect these signa...

Artist concept of the planetary body 2014 UZ224, more informally known as DeeDee. ALMA was able to observe the faint millimeter-wavelength “glow” emitted by the object, confirming it is roughly 635 kilometers across. At this size, DeeDee should have enough mass to be spherical, the criteria necessary for astronomers to consider it a dwarf planet, though it has yet to receive that official designation. Credit: Alexandra Angelich (NRAO/AUI/NSF)

Using ALMA, astronomers have revealed extraordinary details about a recently discovered far-flung member of our solar system, the planetary body 2014 UZ224 aka DeeDee...

This is an artist’s impression of gas generation from the collision between objects in a debris disk. Credit: RIKEN

By examining the atomic carbon line from 2 young star systems – 49 Ceti and Beta Pictoris – researchers had found atomic carbon in the disk, the first time this observation has been made at sub-millimeter wavelength, hinting that the gas in debris disks is not primordial, but rather is generated from some process of collisions taking place in the debris disk. Many young stars, as well as more middle-aged stars like our sun, have “debris disks” – like the Oort Cloud in our own solar system – that are believed to be remnants of the system’s formation. Recently, radio observations have detected gas within a number of such discs, but it was not clear why the gas was there...

LSU Department of Physics & Astronomy Assistant Professor Ivan Agullo’s new research advances knowledge of a classical theory of electromagnetism. Credit: LSU

Discovery may impact the study of the birth of the universe. Radio waves, microwaves and even light itself are all made of electric and magnetic fields. The classical theory of electromagnetism was completed in the 1860s by James Clerk Maxwell. At the time, Maxwell’s theory was revolutionary, and provided a unified framework to understand electricity, magnetism and optics. Now, new research led by LSU Dept of Physics & Astronomy Assistant Prof. Ivan Agullo, with colleagues from Universidad de Valencia advances knowledge of this theory.

Maxwell’s theory displays a remarkable feature: it remains unaltered under the interchange of the e...