A newly discovered impact crater on Mars was likely left by an enormous asteroid that slammed into the Red Planet around 3.4 billion years ago and may have triggered an 800-foot-tall “mega-tsunami.” The colossal explosion was similar to the asteroid impact on Earth that wiped out the nonavian dinosaurs, a new study shows. From about … Read more
Astronomers estimate that roughly 85% of all the matter in the universe is dark matter, meaning only 15% of all matter is normal matter. Accounting for dark energy, the name astronomers give to the accelerated expansion of the universe, dark matter makes up roughly 27% of all the mass energy in the cosmos, according to … Read more
The winter solstice heralds the astronomical start of winter and marks the day with the fewest hours of daylight for the year. But what’s the science behind the shortest day and longest night? The winter solstice — and for that matter, the four seasons — occur because Earth is tilted at an angle of about … Read more
A team of scientists has proposed building an “interstellar interceptor,” a spacecraft capable of getting up-close and personal with the next asteroid or comet to enter the solar system. So far, astronomers have spotted two such objects whizzing through our star system: The cigar-shaped interstellar visitor ‘Oumuamua, which was first spotted in October 2017 and … Read more
The universe may seem shapeless because it is so vast, but it does have a form that astronomers can observe. So, what is it shaped like? Physicists think the universe is flat. Several lines of evidence point to this flat universe: light left over from the Big Bang, the rate of expansion of the universe … Read more
Astronomers have detected an enormous extragalactic structure hiding in an uncharted region of space far beyond the Milky Way’s center. This phantom region, known as the zone of avoidance, is a blank spot on our map of the universe, comprising somewhere between 10% and 20% of the night sky. The reason we can’t see it … Read more
Scattered across the vacuum of space are stars, galaxies, stellar remnants and other objects that are billions upon billions of years old. The age of the universe is now thought to be about 13.8 billion years — almost unfathomable. But how do we know that? We can determine the age of the universe (to an … Read more
Scholars may have just discovered a fragment of the world’s oldest complete star map. The map segment, which was found beneath the text on a sheet of medieval parchment, is thought to be a copy of the long-lost star catalog of the second century B.C. Greek astronomer Hipparchus, who made the earliest known attempt to … Read more
A potentially hazardous near-Earth asteroid is spinning faster and faster every year, and researchers aren’t sure why. The space rock, known as 3200 Phaethon, is around 3.4 miles (5.4 kilometers) wide, and its orbit through the solar system takes it closer to the sun than any other named asteroid, reaching a minimum distance of around … Read more
Astronomers have spotted a black hole mysteriously spewing up chunks of a devoured star several years after consuming it. The event, which scientists have classified as AT2018hyz, began in 2018 when astronomers saw the black hole ensnare a hapless star in its strong gravitational pull before shredding it to pieces. Then, three years later, in … Read more
