A guide to cosmic fireworks, from stellar flares to black-hole beacons


Share post:

New Scientist Default Image

TO HUMAN eyes, the night sky is serene, save for the moon and a few wandering planets. Peer into space with a telescope that can scan the entire sky in days, however, and it appears as a great cosmic fireworks display – a riot of bangs and flashes radiating across the electromagnetic spectrum, from radio waves to gamma rays.

Astronomers are eager to catch these fleeting astrophysical phenomena, known as transients, because they can reveal a great deal about the universe, from what matter does in the most extreme conditions to how the cosmos evolved. And we are about to see a lot more of them thanks to the Vera C. Rubin Observatory in Chile, which is expected to detect 10 million transients a night when it switches on next year.

The trouble is that, for the untrained observer, it can be difficult to make sense of transients. For starters, similar-looking outbursts can have different origins and vice versa, such that a single source can give rise to a variety of astrophysical signatures. That alone can make it tricky to keep track of what’s what.

Here, then, is a concise primer that also serves as a guide to the causes and consequences of these ephemeral illuminations – and how, in some cases, they challenge our understanding of the physics that governs the universe.

Stellar flares

A living star’s electromagnetic eruptions

Let’s start with an easy one. A stellar flare is an explosion in the atmosphere of a star that results in an intense flash of radiation across the electromagnetic spectrum. When our sun flares, for instance, we see a sudden burst of brightness before it quickly …

Source link


Please enter your comment!
Please enter your name here

Related articles

Tesla Autopilot arbitration win could set legal benchmark in auto industry

In a victory for Tesla, a California federal judge ruled over the weekend that a group of...

Max Q: Mining moon water

Hello and welcome back to Max Q! In this issue: Mining water on the moon with Starpath Robotics News from...

Republicans still don’t know how to talk to young voters online

In an appeal to younger voters, Republican presidential candidate Vivek Ramaswamy — who proposed raising the voting...

Ousted Flexport CEO Dave Clark strikes back

Dave Clark, the former Amazon executive who was ousted as CEO of Flexport just a year into...