Astronomy Archives - Page 3 of 29

Category: Astronomy

Satellites and space junk may make dark night skies brighter, hindering astronomy and hiding stars from our view

March 27, 2023

Since time immemorial, humans around the world have gazed up in wonder at the night sky.

The starry night sky has not only inspired countless works of music, art and poetry, but has also played an important role in timekeeping, navigation and agricultural practices in many traditions.

For many cultures, the night sky, with its stars, planets and the Milky Way, is considered just as important a part of the natural environment as the forests, lakes and mountains below.

Starlink satellites already leave streaks on astronomical photographs – but growth in satellites and debris will make the whole sky brighter. ( Rafael Schmall / NOIRLab, CC BY)

Countless people around the world gaze at the night sky: not only amateur and professional astronomers, but also casual observers who enjoy looking up at the stars to contemplate our place in the cosmos.

However, the night sky is changing.

Not only is

Astronomy expert squashes extra-terrestrial rumors about mysterious lights

March 25, 2023

What we know about the lights that streaked across the sky in Sacramento

02:26

SACRAMENTO – When a sudden string of lights raced through the sky Friday night, people whipped out their cell phones to capture it.

“Wow. What is that?!” You could hear the excitement on one viewer’s cell phone video. “I’ve never seen a tail like that. Are these spaceships? That is amazing.”

Raj Dixit says it’s just an old satellite that went ‘belly up.’ The Vice President of the Sacramento Valley Astronomical Society put all the extra-terrestrial rumors to rest.

“This was an old Japanese communication satellite known as ICS. It was lost to the International Space Station back in 2009 and then quickly died and became space junk,” Dixit told CBS13.

While that satellite was launched back in 2009, it took more than

Mysterious radio signal reveals intricate core of galaxy cluster

March 24, 2023

A puzzling radio emission from a galactic cluster located in the constellation may come from the 1.66 million light-year-long radio tail of its dominating central galaxy.

The team that made this discovery also found evidence of mergers between galaxies in the cluster Abell 1213, which is in the constellation of Ursa Major and is located around 647 million light-years from Earth. The findings are the result of astronomers investigating an anomalous radio emission from Abell 1213. In 2009, observations with the Very Large Array (VLA), comprised of 28 radio antennas spread across the Plains of New Mexico, revealed the presence of a diffuse extended emission from the cluster.

This was initially believed to be from a radio halo, a large-scale source of diffuse (spread out) radio emissions found at the heart of a select few galactic clusters that are created when electrons moving in a circle are accelerated to near-light

The forgotten maths genius who laid the foundations for Isaac Newton | Astronomy

March 23, 2023

On a cloudy afternoon in England in 1639, 20-year-old Jeremiah Horrocks became the first person to accurately predict the transit of Venus and measure the distance from the Earth to the sun.

His work proved, for the first time, that Earth is not at the centre of the universe, but revolves around the sun, refuting contemporary religious beliefs and laying the foundations for Isaac Newton’s groundbreaking work on gravity.

Yet today Horrocks has been “almost forgotten” and few are aware of the important contributions he made to the field of astronomy. Due to his untimely death at the age of 22, his work was never published in his lifetime and he never gained widespread recognition for his dazzling mathematical achievements.

“Without Horrocks, all the pieces wouldn’t have been

Let there be (natural) light

March 22, 2023

Light pollution affects every region on Earth, including at the poles and even above us in low-Earth orbit. That isn’t news. But the extent of the problem, laid out in our Focus on dark skies, is startling and should turn us all into activists.

On 23 February 2023, Ynys Enlli in north Wales joined a growing list of geographically remote International Dark Sky Sanctuaries, which includes the Pitcairn Islands and !Ae!Hai Kalahari Heritage Park, South Africa. These sites must meet strict criteria for the quality of the night sky and are only designated after extensive monitoring.

Credit: reproduced under a Creative Commons licence CC BY 4.0

While each additional protected dark sky location is a win, we need to address the underlying causes that necessitate intervention in the first place. Our Focus on dark skies looks at just that. The authors not only point out the various problems — and

Astronomy light, natural