My tenth page... The End of the World (the science)

 ASTEROID APOPHIS 

End of the World?

 

There may be millions of asteroids out there, but does that mean we’re doomed just like the dinosaurs? Take a look at the actual risk that asteroids and other near-Earth objects pose, when you need to worry, and when you don’t. Plus, watch our newest video that breaks down the five steps we can take to avoid a planetary disaster: find, track, characterize, deflect, and coordinate and educate.

Pictured: An artist’s impression of an asteroid approaching Earth.

We’re not just preserving life on this planet; we’re looking elsewhere for it too! One of the big questions facing researchers involved in the search for life beyond Earth is how we’ll recognize alien life if we do find it, since all we currently know is Earth-like life. Planetary Society board member and Cornell University planetary scientist Britney Schmidt joins this week’s Planetary Radio to talk about this challenge and share some insights into how researchers like her address it — including with a sub-ice exploring robotic submarine.

 

A huge asteroid is coming near Earth in seven years — and we’re getting ready for it. The 400-meter asteroid Apophis will fly by Earth in 2029, coming closer than our geostationary satellites. Scientists are sure that it won’t hit the Earth, but it will provide an unparalleled opportunity to study an asteroid and to raise public awareness about the asteroid threat. The Planetary Society participated in a conference last week to plan for this event and prepare to make the most of it.

 ASTEROID APOPHIS

Apophis is a near-Earth asteroid, meaning its orbit around the Sun brings it within 1.3 times the distance between the Sun and Earth. Its full name is Apophis 99942. After Apophis was discovered in 2004, the asteroid was given a 2.7% chance of hitting Earth in 2029, causing a great deal of media attention. It also for a time had a small chance of hitting Earth in 2036. Additional observations have shown it will not hit Earth in 2029 or in 2036.

 

Nevertheless, in 2029 Apophis will come closer to Earth than our geostationary communications satellites, likely sparking a great deal of public interest.

 

APOPHIS IN NEW YORK CITY Asteroid Apophis would fit neatly inside The Battery, a park at the tip of Manhattan in New York City. This image shows an artist's concept of Apophis in the park to illustrate its size in comparison to the rest of the New York City skyline. The image is free for media and educational use with attribution.Image: The Planetary Society

How big is Apophis?

 Like most asteroids, Apophis is too small for us to figure out its exact shape and size from Earth. Radar images have shown it measures 450 meters (1500 feet) across its longest axis, equivalent to about 5 football fields and taller than the Empire State Building in New York City. It is approximately 170 meters on its shortest axis.

 

Will Apophis hit Earth?

 Not anytime soon. It definitely will miss Earth in 2029 and 2036, and radar observations of Apophis during the asteroid's flyby in March 2021 ruled out an impact for at least the next 100 years.

 

What would happen if Apophis hit Earth?

 Apophis would cause widespread destruction up to several hundred of kilometers from its impact site. The energy released would be equal more than 1,000 megatons of TNT, or tens to hundreds of nuclear weapons.

 

How big was the asteroid that killed the dinosaurs?

 The asteroid that led to the extinction of the dinosaurs as well as 70% of all species on Earth was at least 10 to 15 kilometers wide. It was much larger than Apophis, though millions of people could still die if an Apophis-sized asteroid struck a major metropolitan area.

 

How close will Apophis come to Earth in 2029?

 On 13 April 2029 Apophis will pass as close as 30,600 kilometers (19,000 miles) above the Earth. If you’re superstitious, that's on a Friday the 13th.

 

How close will Apophis come to Earth in 2036?

 On 30 March 2036 Apophis will pass Earth at a much further distance: 8.4 million kilometers (5.2 million miles). That’s more than 20 times the distance between the Earth and Moon.

Could we stop an asteroid like Apophis?

 With enough warning time before impact, meaning many years, we could change the orbit of an asteroid the size of Apophis enough to cause it to miss the Earth, but this would require a coordinated global effort. To learn more about planetary defense including deflecting asteroids see our planetary defense page

http://planetary.org/defense

 

Will we be able to see Apophis?

 During the 2029 pass Apophis will be visible from Europe, Africa, and western Asia looking like a somewhat bright star (magnitude 3.1) moving rapidly across the sky. It will be much too far away to be visible without telescopes in 2036.

 

Fonte:

Links:

https://www.planetary.org/articles/will-apophis-hit-earth?autologin=true&utm_campaign=downlink&utm_medium=email&utm_source=20220520&s_src=downlink&s_subsrc=20220520

 

How to stop an asteroid from hitting Earth

https://www.planetary.org/video/how-to-stop-an-asteroid-from-hitting-earth?autologin=true&utm_campaign=downlink&utm_medium=email&utm_source=20220520&s_src=downlink&s_subsrc=20220520

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