Space and astronomy news
Venus is often described as a hellscape. The surface temperature breaches the melting point of lead, and though its atmosphere is dominated by carbon dioxide, it contains enough sulfuric acid to satisfy the comparison with Hades.
But conditions throughout Venus’ ample atmosphere aren’t uniform. There are locations where some of life’s building blocks could resist the planet’s inhospitable nature.
Continue reading “Another Building Block of Life Can Handle Venus’ Sulphuric Acid”
When a massive star explodes as a supernova, it does more than release an extraordinary amount of energy. Supernovae explosions are responsible for creating some of the heavy elements, including iron, which is blasted out into space by the explosion. On Earth, there are two accumulations of the iron isotope Fe60 in sea-floor sediments that scientists trace back about two or three million years ago and about five to six million years ago.
The explosions that created the iron also dosed Earth with cosmic radiation.
Continue reading “How a Nearby Supernova Left its Mark on Earth Life”
Earth’s last half-billion years were action-packed. During that time, the climate underwent many changes. There have been changes in ocean levels and ice sheets, changes in the atmosphere’s composition, changes in ocean chemistry, and ongoing biological evolution punctuated with extinction events.
A record of Earth’s temperature over the last 485 million years is helping scientists understand how it all played out and illustrating what could happen if we continue to enrich the atmosphere with carbon.
Continue reading “From Frozen to Sweltering: Earth’s Climate Over the Last 485 Million Years”
NASA’s Juno spacecraft was sent to Jupiter to study the gas giant. But its mission was extended, giving it an opportunity to study the unique moon Io. Io is the most volcanically active body in the Solar System, with over 400 active volcanoes.
Researchers have taken advantage of Juno’s flybys of Io to study how tidal heating affects the moon.
Continue reading “Io’s Volcanoes are Windows into its Hot Interior”
Photosynthesis changed Earth in powerful ways. When photosynthetic organisms appeared, it led to the Great Oxygenation Event. That allowed multicellular life to evolve and resulted in the ozone layer. Life could venture onto land, protected from the Sun’s intense ultraviolet radiation.
But Earth’s photosynthetic organisms evolved under the Sun’s specific illumination. How would plants do under other stars?
Continue reading “Plants Would Still Grow Well Under Alien Skies”
The Sun is midway through its life of fusion. It’s about five billion years old, and though its life is far from over, it will undergo some pronounced changes as it ages. Over the next billion years, the Sun will continue to brighten.
That means things will change here on Earth.
Continue reading “Life Might Thrive on the Surface of Earth for an Extra Billion Years”
The Hubble Deep Field and its successor, the Hubble Ultra-Deep Field, showed us how vast our Universe is and how it teems with galaxies of all shapes and sizes. They focused on tiny patches of the sky that appeared to be empty and revealed the presence of countless galaxies. Now, astronomers are using the Hubble Ultra-Deep Field and follow-up images to reveal the presence of a large number of supermassive black holes in the early Universe.
This is a shocking result because, according to theory, these massive objects shouldn’t have been so plentiful billions of years ago.
Continue reading “The Early Universe Had a Lot of Black Holes”
Astronomers have solid evidence for the existence of stellar-mass black holes and supermassive black holes. However, evidence for Intermediate Black Holes (IMBHs) is more elusive. Their existence remains hypothetical.
However, study by study, evidence is accumulating for IMBHs. The latest comes from the globular cluster M15, where a fast-moving star suggests the presence of something massive. Could it be an elusive IMBH?
Continue reading “A Star Was Kicked Out of a Globular Cluster by an Intermediate-Mass Black Hole”
Is it time for space lasers yet? Almost.
As time passes, ideas that were once confined to the realm of science fiction become more realistic. It’s true of things like using robots to explore other worlds. Space lasers are a well-used element in science fiction, and we’re approaching the time when they could become a reality.
Where would we put them, and what could we use them for?
Continue reading “There are Plenty of Uses for Powerful Lasers in Space. But Where Should We Put Them?”
When the James Webb Space Telescope was launched on Christmas Day in 2021, it faced a whole host of intriguing questions. By the time it finally launched, astronomers had a big list of targets begging for the type of detailed observations that only the powerful infrared space telescope could perform. One of the targets was an ancient, massive galaxy that’s basically dead and forms no new stars.
The results are in, and an international team of astronomers know what happened to the quiescent galaxy.
Continue reading “A Black Hole has Almost Halted Star Formation in its Galaxy”