When searching for potentially habitable exoplanets, scientists are forced to take the low-hanging fruit approach. Since Earth is the only planet we know of that is capable of supporting life, this search basically comes down to looking for planets that are “Earth-like”. But what if Earth is not the meter stick for habitability that we all tend to think it is?
That was the subject of a keynote lecture that was recently made at the Goldschmidt Geochemistry Congress, which took place from Aug. 18th to 23rd, in Barcelona, Spain. Here, a team of NASA-supported researchers explained how an examination of what goes into defining habitable zones (HZs) shows that some exoplanets may have better conditions for life to thrive than Earth itself has.
Continue reading “There Could be Planets Out There Which are Even More Habitable than Earth”
When an extraterrestrial object slams into the Earth, it sends molten rock high into the atmosphere. That debris cools and re-crystallizes and falls back down to Earth. Tiny glass beads that form in this process are called microtektites, and researchers in Florida have found microtektites inside fossilized clams.
Continue reading “Fossilized Clams Had Evidence of a Meteorite Impact Inside Them”
In 2008, scientists from Oxford and Aberdeen University made a startling discovery in the northwest of Scotland. Near the village of Ullapool, which sits on the coast opposite the Outer Hebrides, they found a debris deposit created by an ancient meteor impact dated to 1.2 billion years ago. The thickness and extent of the debris suggested that the meteor measured 1 km (0.62 mi) in diameter and took place near to the coast.
Until recently, the precise location of the impact remained a mystery to scientists. But in a paper that recently appeared in the Journal of the Geological Society , a team of British researchers concluded that the crater is located about 15 to 20 km (~9 to 12.5 mi) west of the Scottish coastline in the Minch Basin, where it is buried beneath both water and younger layers of rock.
Continue reading “1.2 billion years ago, a 1-km asteroid smashed into Scotland”
According to a new NASA-funded study that appeared in Astrobiology, the next missions to Mars should be on the lookout for rocks that look like “fettuccine”. The reason for this, according to the research team, is that the formation of these types of rocks is controlled by a form of ancient and hardy bacteria here on Earth that are able to thrive in conditions similar to what Mars experiences today.
Continue reading “Rovers on Mars should be searching for rocks that look like pasta – they’re almost certainly created by life”
A strange feature on the surface of Mars has kept scientists guessing about its origin. It’s a surface deposit of a mineral which is more common in the interiors of planets. A new study shows that this interior mineral was probably brought to the surface by an ancient explosive volcano.
Continue reading “This Strange Feature on Mars was Probably the Result of an Ancient Volcanic Explosion”
Everyone knows an asteroid strike wiped out the dinosaurs, right? Lots of evidence shows that the Chicxulub impact event had terrible consequences for the dinosaurs. But the picture is a little more complicated than that. Extreme volcanic activity may have contributed to the extinction.
Continue reading “Massive Volcanic Eruptions 66 Million Years Ago Happened Almost Exactly When the Dinosaurs Died Off”
A glaciologist has discovered another enormous impact crater under more than a mile of ice in Greenland. This is on the heels of the November 2019 discovery of an impact crater in the same area under the Hiawatha Glacier. The November discovery was the first-ever crater found under ice on Earth.
Continue reading “Another Enormous Crater Found Under the Ice in Greenland”
The Earth wasn’t formed containing the necessary chemicals for life to begin. One well-supported theory, called the “late veneer theory”, suggests that the volatile chemicals needed for life arrived long after the Earth formed, brought here by meteorites. But a new study challenges the late veneer theory.
Evidence shows that the Moon was created when a Mars-sized planet named Theia collided with the Earth. The impact created a debris ring out of which the Moon formed. Now, this new study says that same impact may have delivered the necessary chemicals for life to the young Earth.
Continue reading “Without the Impact that Formed the Moon, We Might Not Have Life on Earth”
Since they were first observed in the 1970s by the Viking missions, the slope streaks that periodically appear along slopes on Mars have continued to intrigue scientists. After years of study, scientists still aren’t sure exactly what causes them. While some believe that “wet” mechanisms are the culprit, others think they are the result of “dry” mechanisms.
Luckily, improvements in high-resolution sensors and imaging capabilities – as well as improved understanding of Mars’ seasonal cycles – is bringing us closer to an answer. Using a terrestrial analog from Bolivia, a research team from Sweden recently conducted a study that explored the mechanisms for streak formation and suggest that wet mechanisms appear to account for more, which could have serious implications for future missions to Mars.
Continue reading “Planetary Scientists Continue to Puzzle Over the Mysterious Slope Streaks on Mars. Liquid? Sand? What’s Causing Them?”
Earth’s last great ice age, known as the Quaternay Glaciation, began roughly 3.2 million years ago. This period was characterized by the expansion of ice sheets out of Antarctica and Greenland, as well as the fluctuation of the Laurentian ice sheet, which covered most of Canada and the United States. The retreat of this glacier is responsible for the creation of millions of standing bodies of water across North America, including the Great Lakes.
While the causes of ice ages have been attributed to a combination of astronomical cycles, atmospheric conditions, ocean currents and plate tectonics, a complete explanation has been lacking thus far. However, according to a new research findings by a team of Rice University geophysicists, Earth’s last ice age may have been caused by shifts in the Earth relative to its spin axis that caused its poles to wander.
Continue reading “The Earth’s Wandering Poles Could Have Caused the Ice Age”