This matters for Venus because scientists use crater sizes and numbers to estimate the ages of planetary surfaces. Just as trees form rings as they grow, planets without active surface geology accumulate craters over millennia of impacts. By matching a planet's blemishes to the known population of space rocks, scientists can work backward to trace its impact history and get a rough estimate of its surface age. Previous estimates for Venus relied on the handful of objects known to orbit the inner solar system a few decades ago.
Since , NASA's Spaceguard effort has been working to identify and monitor over 90 percent of these near-Earth objects larger than 0. When combined with the revised scaling between asteroids and craters, Bottke found that the estimated age for Venus' skin would change significantly: down to about million years old. McGovern also pointed to research from that suggested crater floors on Venus are filled with basaltic lavas, leading the authors to estimate a planetary surface age of about million years—close to Bottke's range.
According to McGovern, this research is still being debated, which makes the new results even more significant. The result, which Bottke is now submitting for publication, is very surprising, adds comet and asteroid researcher Paul Weissman , a senior scientist at the Planetary Science Institute in California. As the material condensed together, conservation of momentum caused it to spin up and flatten out.
A protoplanetary disk of material formed around the newborn Sun, and it was here that the planets formed. Dust clumped together to form rocks, rocks smashed together into boulders, and mountain-sized objects became protoplanets. But eventually, Venus became the dominant object in the region, sucking in everything with its gravity.
Venus' dense cloud cover has benefits for us Earthlings. It reflects the sun's rays, making the planet the brightest in the night sky. It's often called the morning star or evening star because its bright, steady glow persists either around sunrise or sunset. Ancient peoples spotted these dazzling points in the sky and believed them to be two different objects, one that glows in the morning and another that glows in the evening.
Similar to Mercury, Venus can occasionally be seen making a lazy trip across the sun's face, known as a transit. But while Mercury zips across the sun every 13 to 14 years, Venus transits are much more rare. The planet's orbit is almost a perfect circle but is slightly tipped relative to Earth's path around our star. This means it's incredibly hard for the sun, Venus, and Earth to align in the right way.
The last time a transit of Venus happened was in , and it won't happen again until All rights reserved. On September 14, , scientists announced the possible detection of phosphine gas in the clouds of Venus. Find out more about the tantalizing, if controversial, finding here. Share Tweet Email. Why it's so hard to treat pain in infants. This wild African cat has adapted to life in a big city. Animals Wild Cities This wild African cat has adapted to life in a big city Caracals have learned to hunt around the urban edges of Cape Town, though the predator faces many threats, such as getting hit by cars.
India bets its energy future on solar—in ways both small and big. Environment Planet Possible India bets its energy future on solar—in ways both small and big Grassroots efforts are bringing solar panels to rural villages without electricity, while massive solar arrays are being built across the country. Because Venus is easy to spot with the naked eye, it is impossible to say who discovered the planet.
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