Universe Today

September 22, 2021September 23, 2021 by Nancy Atkinson

3,600 Years ago, a 50-Meter-Wide Meteor Exploded in the Sky and Destroyed a City Near the Dead Sea

This is an artist’s depiction of a 10-kilometer (6-mile) diameter asteroid striking the Earth. New evidence in Australia suggests an asteroid 2 to 3 times larger than this struck Earth early in its life. Credit: Don Davis/Southwest Research Institute.

An archeological dig has uncovered evidence of a massive cosmic airburst event approximately 3,600 years ago that destroyed an entire city near the Dead Sea in the Middle East. The event was larger than the famous Tunguska airburst event in Russia in 1908, with a blast 1,000 times more powerful than the Hiroshima atomic bomb. The event flattened the thriving city of Tall el-Hammam, located in what is now Jordan.

September 22, 2021September 25, 2021 by Matt Williams

A Particle Physics Experiment Might Have Directly Observed Dark Energy

An illustration of cosmic expansion. Credit: NASA's Goddard Space Flight Center Conceptual Image Lab

About 25 years ago, astrophysicists noticed something very interesting about the Universe. The fact that it was in a state of expansion had been known since the 1920s, thanks to the observation of Edwin Hubble. But thanks to the observations astronomers were making with the space observatory that bore his name (the Hubble Space Telescope), they began to notice how the rate of cosmic expansion was getting faster!

This has led to the theory that the Universe is filled with an invisible and mysterious force, known as Dark Energy (DE). Decades after it was proposed, scientists are still trying to pin down this elusive force that makes up about 70% of the energy budget of the Universe. According to a recent study by an international team of researchers, the XENON1T experiment may have already detected this elusive force, opening new possibilities for future DE research.

September 22, 2021September 22, 2021 by Andy Tomaswick

NASA has a Ballistic air gun to Hurl Rocks at Space Suits to Test Their Micrometeorite Protection

Shock testing is commonly used throughout engineering to determine how a product will do when impacted by something. That something could be anything from the ground to a cruise missile. Like so much else in space exploration, engineers at NASA are performing the same type of test, just scaled up. Instead of simply dropping the object under test, as is common in most settings, they shoot it with a steel ball going 3000 ft/second.

September 22, 2021September 22, 2021 by David Dickinson

Using Quasars as a New Standard Candle to Define Distance

A new study shows a way to use quasars to gauge distance in the early Universe.

The simple question of ‘how far?’ gets at the heart of the history of modern astronomy. Looking out across our galactic backyard into the primordial Universe, different yardsticks—often referred to as ‘standard candles’ —are used to gauge various distances, from near to far.

September 21, 2021 by Nancy Atkinson

By Using Dashcams and Security Cameras, Astronomers Were Able to Track Down the Location of a Meteorite

A 48-gram piece of the Novo Mesto meteorite. Credit: Bojan Ambroži? (Center of Excellence on Nanoscience and Nanotechnology, Slovenia and https://bojanambrozic.com/).

OK, all you meteorites that are falling to Earth … You are being watched!

The ever-expanding use of security cameras, doorbell cams and vehicle dashcams have increased the number of fireballs that have been spotted streaking across the skies. And sometimes, all that visual data provides the side benefit of allowing rocks from space to be tracked and found.

September 21, 2021September 21, 2021 by Andy Tomaswick

A LEGO® Version of the Very Large Telescope. It Even has a Laser Interferometer

Interferometers are some of the most highly advanced sensor instruments that humans have made. They are used in everything from astronomy to quantum mechanics and have profoundly impacted our understanding of science. But not all interferometers have to be functional. A Dutch astronomer named Frans Snik has just designed one that, while it isn’t function, is inspiring all the same – and it happens to be made out of Lego.

September 20, 2021September 20, 2021 by Alan Boyle

NASA’s VIPER Rover Will Hunt for Water Near Nobile Crater at Moon’s South Pole

A data visualization shows the mountainous area west of Nobile Crater and the smaller craters that litter its rim at the lunar south pole. The region includes permanently shadowed areas where subsurface water ice could persist, as well as sunlit areas that would make it possible to power the VIPER rover. (NASA Graphic)

NASA says its VIPER rover will head for the western edge of Nobile Crater near the moon’s south pole in 2023, targeting a region where shadowed craters are cold enough for water ice to exist, but where enough of the sun’s rays reach to keep the solar-powered robot going.

Today’s announcement provides a focus for a mission that’s meant to blaze a trail for Artemis astronauts who are scheduled to land on the lunar surface by as early as 2024, and for a sustainable lunar settlement that could take shape by the end of the decade.

“Once it’s on the surface, it will search for ice and other resources on and below the lunar surface that could one day be used and harvested for long-term human exploration of the moon,” Lori Glaze, director of the planetary science division at NASA’s Science Mission Directorate, said during a teleconference.

September 20, 2021September 20, 2021 by Evan Gough

How Could we Light our Cities and Still See the Night Sky?

Standing beside the Milky Way. Drowming out the night sky blocks us off from nature, and that's not good for humans. Credit: P. Horálek/ESO

The night sky is a part of humanity’s natural heritage. Gazing up at the heavens is a unifying act, performed by almost every human that’s ever lived. Haven’t you looked up at the night sky and felt it ignite your sense of wonder?

But you can’t see much night sky in a modern city. And the majority of humans live in cities now. How can we regain our heritage? Can quiet contemplation make a comeback?

September 20, 2021September 20, 2021 by Nancy Atkinson

Accurately Forecasting the Weather on Mars and Titan

Illustration by Michael S. Helfenbein; Image courtesy of NASA/JPL-Caltech.

Even meteorologists who forecast the weather on Earth admit that they can’t always accurately predict the weather at a specific location on our planet any given time. And so, attempting to forecast the atmospheric conditions on another world can be downright impossible.

But a new study suggests that an oft-used forecasting technique on Earth can be applied to other worlds as well, such as on Mars or Titan, Saturn’s largest moon.

September 20, 2021September 20, 2021 by Evan Gough

The Moon was Pummeled Even Harder by Asteroids Than it Looks

We intend to explore the Moon, use its resources, and use it as a jumping-off point for missions deeper into the Solar System. For that we need a Lunar GPS. Image Credit: NASA

The Moon’s pitted surface tells a tale of repeated impacts over a long period of time. While Earth’s active geology erases most evidence of impacts, the Moon has no mechanism that can do the same. So there it sits, stark evidence of an impact-rich past.

The visible record of lunar cratering is used to understand Earth’s formation and history since periods of frequent impacts would affect both bodies similarly. But something’s wrong in our understanding of the Moon’s history. Impact crater dating, asteroid dynamics, lunar samples, impact basin-forming simulations, and lunar evolution modelling all suggest there’s some missing evidence from the Moon’s earliest impacts.

New research says that there were even more large, basin-forming impacts than we think. Scientists think that some of those impacts left crater imprints that are nearly invisible.