Category Astronomy/Space

Ryugu asteroid samples contain all DNA and RNA building blocks, bolstering origin-of-life theories

The black particles from an asteroid some 300 million kilometres away look unremarkable, but they hold components of life
The black particles from an asteroid some 300 million kilometers away look unremarkable, but they hold components of life.

All the essential ingredients to make the DNA and RNA underpinning life on Earth have been discovered in samples collected from the asteroid Ryugu, scientists said Monday.

The discovery comes after these building blocks of life were detected on another asteroid called Bennu, suggesting they are abundant throughout the solar system.

One longstanding theory is that life first began on Earth when asteroids carrying fundamental elements crashed into our planet long ago.

The asteroids that hurtle through our solar system give scientists a rare chance to study this possibility.

In 2014, the Japanese spacecraft Hayabusa-2 blasted off on a 300-million-kilometer...

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Scientists crack a 20-year nuclear mystery behind the creation of gold

Peter Dyszel

Gold cannot form until certain unstable atomic nuclei break apart. Exactly how those nuclear transformations unfold has long been difficult to determine. Now, nuclear physicists at the University of Tennessee (UT) report three discoveries in a single study that clarify important parts of this process. Their findings could help researchers build improved models of the stellar events that create heavy elements and better predict the behavior of exotic atomic nuclei.

Heavy elements such as gold and platinum are forged under extraordinary conditions, including when stars collapse, explode, or collide. These events trigger the rapid neutron capture process (or r-process for short). During this process, an atomic nucleus absorbs neutrons in rapid succession...

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We are not alone: Our sun escaped together with stellar ‘twins’ from galaxy center

A mass migration of stellar twins.
A mass migration of stellar twins. Stars similar to our Sun form a mass migration from the center of the Milky Way, occurring approximately 4 to 6 billion years ago.
Credit NAOJ

Researchers have uncovered evidence for our sun joining a mass migration of similar “twins” leaving the core regions of our galaxy, 4 to 6 billion years ago. The team created and studied an unprecedentedly accurate catalog of stars and their properties using data from the European Space Agency’s Gaia satellite. Their discovery sheds light on the evolution of our galaxy, particularly the development of the rotating bar-like structure at its center.

While archaeology on Earth studies the human past, galactic archaeology traces the vast journey of stars and galaxies...

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Hydrogen atmosphere could keep exomoons habitable for billions of years

Life-friendly moon
A realistic depiction of a free-floating gas giant planet and its Earth-like moon
© Dahlbüdding/DALL-E

Liquid water is considered essential for life. Surprisingly, however, stable conditions that are conducive to life could exist far from any sun. A research team from the Excellence Cluster ORIGINS at LMU and the Max Planck Institute for Extraterrestrial Physics (MPE) has shown that moons around freefloating planets can keep their water oceans liquid for up to 4.3 billion years by virtue of dense hydrogen atmospheres and tidal heating—that is to say, for almost as long as Earth has existed and sufficient time for complex life to develop.

Planetary systems often form under unstable conditions...

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