Category Astronomy/Space

This is the “South Pillar” region of the star-forming region called the Carina Nebula. Like cracking open a watermelon and finding its seeds, the infrared telescope “busted open” this murky cloud to reveal star embryos tucked inside finger-like pillars of thick dust. Credit: NASA

A type of gas found in the voids between galaxies – atomic gas – appears to be part of the star formation process under certain conditions. The findings overturn a long-standing theory about the conditions needed for star formation to take place – a process that happens when dense clouds of dust and gas inside galaxies collapse.

It was previously thought that stars could form only in the presence of a different type of gas – called molecular gas. Atomic gas is composed of individual H atoms...

Coronal loops on the sun that are linked to magnetic fields. Credit: NASA/Solar Dynamics Observatory Read more at: http://phys.org/news/2015-11-physicists-clue-formation-magnetic-fields.html#jCp

Small magnetic perturbations can combine to form large-scale magnetic fields just like those found throughout the universe. Squire and Bhattacharjee at PPPL analyzed the behavior of dynamos, which occur when an electrically charged fluid like plasma swirls in a way that creates and then amplifies a magnetic field. Scientists have known that plasma turbulence can create lots of small magnetic fields, but the mechanism by which those fields could produce a single large field is elusive.

The puzzle consists of the seeming unlikelihood of small disturbances coming together to form something large and o...

This is an optical image with radio lobes (in yellow-red). The supermassive black hole in the red galaxy at the centre (zoomed in inset) has led to the formation of the giant radio lobes. Credit: Prathamesh Tamhane/Yogesh Wadadekar

Astronomers have discovered an extremely rare radio galaxy – a giant, with an extent of 4 million light years caught in its dying phase at an incredible distance of 9 billion light years. This discovery, made by combining observations of the Giant Metrewave Radio Telescope, with other telescopes in space and on the ground, enables us to study properties of the magnetic field in the region between galaxies in the distant universe.

How do galaxies with an optical size of a hundred thousand light years produce radio emission several million light years in extent? I...

Allen Telescope Array. Credit: Seth Shostak, SETI Institute

A recent analysis of data collected by Kepler space telescope has shown that this star, informally known as Tabby’s Star, evidences aperiodic dimming of 20% and more. While several natural explanations for this strong change in luminosity have been proposed, one possibility is that a technologically adept civilization has built megastructures in orbit around star, causing the dimming.

One example of a large-scale astroengineering project would be the construction of a so-called Dyson swarm of solar panels for large-scale energy collection. Other possible structures include artificial space habitats, or a planet-size or larger occulting object intended to provide a long-lasting signal to other galactic inhabitants.

In order to inve...