“If you’re a really good passer in football, you line up the axis of rotation with the axis of symmetry of the football, and it doesn’t wobble,” McCarthy said. When a player tosses a football, it wobbles slightly as it rotates since it often doesn’t spin around the axis of symmetry, he said. This creates a slight wobble as the Earth rotates, similar to how a football wobbles when it is thrown, he said. The axis our planet rotates on is not lined up with its axis of symmetry, an invisible vertical line that divides the Earth into two equal halves. Some have suggested a correlation with the Chandler wobble, McCarthy said. When they tuck their arms close to their body, their speed increases because their body mass is closer to their center of gravity, McCarthy said.Īs Earth becomes rounder, its mass becomes closer to its center, which increases its rotational speed, he said. When skaters stretch their arms away from their body as they spin, it takes more force for them to rotate, he said. Mysterious bundle of string on Mars' surface found by Perseverance rover NASA's Perseverance rover captured a photo of a small bundle of string while exploring Jezero Crater. It’s the same phenomenon that figure skaters use to increase and decrease their speed, he said. The circular shape helps the planet spin faster, McCarthy said. Since the poles are melting due to the climate crisis, there is less pressure on the top and bottom of the planet, which moves the crust up and makes the Earth rounder, he said. The glaciers at the poles weigh down on the Earth’s crust at the North and South poles, McCarthy said. Researchers do not have a definitive answer on how or why Earth is turning slightly faster, but it may be due to glacial isostatic adjustment, or the movement of land due to melting glaciers, McCarthy said.Įarth is slightly wider than it is tall, which makes it an oblate spheroid, he said. In the past few years, it began speeding up, McCarthy said. Since 1820, scientists documented Earth’s rotation slowing down, according to NASA. When dinosaurs still roamed the planet 70 million years ago, a single day on Earth lasted about 23 1/2 hours, according to a 2020 study published in Paleoceanography and Paleoclimatology. The atomic clock is a standardized unit of measurement that has been used since the 1950s to tell time and measure the Earth’s rotation, said Dennis McCarthy, retired director of time at the US Naval Observatory.ĭespite June 29 breaking a record for the shortest day in modern history, there have been much shorter days on Earth, he said. The previous record was documented on July 19, 2020, when the day measured 1.47 milliseconds shorter than normal. Rare type of galaxy dazzles in new Webb telescope image A large pink speckled galaxy resembling a wheel with with a small inner oval with dusty blue in between on the right with two smaller spiral galaxies about the same size to the left against a black background.
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