This is according to three studies on two asteroids, one of them close to Earth, published at the end of the week. Scientists are gathering in Washington to discuss the threat from near-Earth objects
Two unrelated asteroids have turned sunlight into an engine that allows them to accelerate the rate of rotation around themselves by returning the sunlight they absorbed into space. This is according to three different studies published this week
Asteroids 2000 PH5 and 1862 Apollo are the first in which a precise measurement of the influence of sunlight reflection on the rotation of "the asteroids, which are relatively small space rocks, was performed. Asteroids are the bodies that have changed the least since the formation of the solar system 4.5 billion years ago." says astronomer Stephen Lowry (Lowry) from the University of Belfast in Ireland, who led the study of asteroid 2000 PH5.
When a large part of the asymmetric asteroid faces the Sun, this causes it to spin because it may radiate more energy from some areas and less from other areas and this causes the spin rate to change. The phenomenon, which has been predicted for a long time but has not been observed until now, is called the Yarkovsky-O'Keefe-Radzievskii-Paddack effect (Yarkovsky-O'Keefe-Radzievskii-Paddack) after the researchers who first described it.
"The Yorp effect plays an important role in changing the trajectory of asteroids between Mars and Jupiter, including moving them into orbits that cross the orbits of planets," says Lori and points to the most alarming phenomenon today - asteroids that threaten to collide with Earth. The strength of the impact is small for the asteroid 2000 PH5 - and it causes its rotation to accelerate by only fractions of a second per year, however, for the Apollo asteroid, which is larger, the cumulative effect causes it to complete another self-rotation in the entire circle of the sun. Find the research.
Asteroid 2000 PH5 is a near-Earth asteroid with a total radius of 57 meters and it completes a self-rotation every 12.17 minutes, meaning a very short day on its surface, certainly compared to the 24-hour self-rotation of the Earth.
Observations made of the asteroid between 2001 and 2005 showed that its day is shortening by a millisecond per year, which means its spin is increasing over time, Lowry says. The study was widely published on March 9 alongside a separate study on the same asteroid led by researcher Patrick Taylor of Cornell, who used radar observations.
"We expect the rate of change to be small, but in theory, it takes millions of years to see a big effect," says Lowry, who added that his team used many telescopes to monitor the asteroid's brightness and rotation rate.
However, as mentioned, a better example of the Yorp effect was given in another study led by Mikko Kaslainen from the Rolf Nunlina Institute in Finland, who discovered as mentioned that the Apollo asteroid, which is 1,400 meters wide, receives a boost from sunlight in the last 40 years so that it is currently performing another rotation, or another asteroid day, every The coffee of the sun. This study was published in the online version of the journal Nature. "The change is relatively large and is clearly visible in the photometric light curves" say the researchers.
Astronomers from all over the world gathered in Washington this week to try and develop a plan to protect the Earth from asteroids. The "Conference for the Protection of the Planet", organized by Aerospace (a government-funded non-profit research organization), brought together dozens of ideas whose purpose is to develop technology to track objects making their way to Earth, and divert them from the collision course. The gathering will also examine the difficult question of whether it is advisable to warn the population if the worst happens?
"The impact of a large asteroid or comet on Earth would have terrible effects," wrote Dr. Brent William Barbee, of Emergent Space Technologies Inc., in a position paper for the meeting. "These events happened and will happen. Nevertheless, for the first time in history, the human race may obtain the necessary technology to prevent the threat."
Many small objects orbiting the Earth disintegrate as they enter the atmosphere, with no effect other than a brief fireworks display. However, a body with a diameter greater than one kilometer, hits the earth once every few hundred thousand years, and a body with a diameter of over six kilometers, which will cause mass extinction, hits the planet once every hundred million years. The experts agree that a giant meteor was already supposed to hit us.
Today, attention is directed towards Apophis, an asteroid with a diameter of 390 meters that was discovered in 2004, and there is a slim chance that it will hit the Earth in 2036. If this happens, the impact will release a hundred thousand times more energy than was released in the nuclear bombing of Hiroshima. Thousands of square kilometers will be directly affected by the explosion. The entire planet will be affected by the dust that will be released into the atmosphere which may cause the destruction of crops around the world.
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This is a level 10 on the Turin scale: a collision that could cause global disaster and climate change, an event that occurs once every 100,000 years or more. The asteroid impact 65 million years ago wiped out the dinosaurs, why not wipe us out? And besides that, in another 20 years we will settle on the moon and another 40 years on Mars, so it doesn't really matter!
If we are all optimistic no one "above" will do anything...
Great article, thanks
Only its ending is apocalyptic and gloomy
As scientists or people from the settlement, we know how to keep calm and not be alarmed by such a severe warning as in the last line of the article, but we must remember
Not everyone knows how to decipher and distill from what is written the poet's intention. Some will read this article and become anxious. It's true, it says there's a slim chance, it's true it's written that they're trying to find ways to divert or disintegrate, it's true that we know about the danger... But still, maybe it's worth trying to end articles on a less dramatic note or on a dramatic but positive note - otherwise, this is a popular magazine.
I hope my feedback will be received positively and not with anger, God forbid, my father. I am a devout reader of your articles and love them very much. Excellent and interesting articles. It's a little scary.
Ami
International cooperation is a high priority.
In order to reduce as much as possible the possible damage of asteroids, which do not distinguish between countries, and their damage is greater than estimated.