NEOs - A Reminder That End Is Near

Sivaraj Kumar
May 3, 2020
3 min read

NEO stands for Near Earth Objects. Small objects that are orbiting the Sun between 0.983 A.U. to 1.3 A.U. They can be classified as follows,

Not all NEOs are deadly. Only a few of them come very close to Earth. Those which come at a distance less than 0.05 A.U. or 19.5 L.D. are called PHOs (Potentially Hazardous Objects). So PHOs are not necessarily bad. They usually miss Earth.

Let's take a look at the asteroid 2020JA.

2020JA

From the name, we can tell it is discovered in 2020. 2-Jan-2020 to be more specific. It is an Apollo type asteroid and it is going to pass very close to Earth on 4-May-2020.

How close you ask? Let's watch the simulation.

So yeah.... It is scary close but no need to panic. It's not going to hit Earth and it is only 10-20 metres in size. Any object with size 10m or so will burn up in the Earth's atmosphere during its entry.

Its closest approach will happen around 1:29am IST. It will be 1.62 times closer than our Moon and will reach maximum magnitude of ~18. So don't expect to see the asteroid with your naked eye.

Only with long exposure photography, the asteroid can be seen.

On 22 April 2020, an object called '2020HU7' came at 0.38 L.D. reaching a maximum magnitude of 4!!!

A GENTLE REMINDER

NEOs and PHOs are a reminder that there are things which we should be really worried about instead of fighting over old fairytales.

There are now more than 150 asteroids known that come nearer to the Sun than the outermost point of Earth's orbit. These range in diameter from a few meters up to about 8 kilometers!

Asteroid 3200 Phaethon which came as close as 0.07A.U. on 17 Dec 2017.

It is 5.1km in diameter. Wooof!

A 1-2km asteroid is enough to bring huge catastrophe on Earth. An object larger than about 5 kilometers can cause mass extinctions. Also virtually any short-period comet among the 100 or so not currently coming near the Earth could become dangerous after a close passage by Jupiter.

CHANCES OF HITTING EARTH

Okay, so there is a large number of objects in space that can bring havoc on Earth but what is the probability of any such asteroid to hit Earth? In any given year it is roughly 1 in 300,000. So not that much.

Remember...

AN EVENT WHICH IS IMPROBABLE IN 100 YEARS MIGHT BECOME INEVITABLE IN 100 THOUSAND YEARS

A dinosaur-killing asteroid can hit Earth every 50 to 70 million years or so. And the dinosaurs went extinct 65 million years ago. Ugh! That doesn't sound so good. But on the bright side, if the large dinosaurs didn't go extinct tiny mammals wouldn't have the chance to evolve into humans.

WHAT WE SHOULD DO

We need big telescopes, both on ground and space, to conduct a large survey of the sky to map all the comets and asteroids around us. We should have a space force that should be able to act at any time to protect Earth.

We should also create a backup on Mars, if humans become extinct by asteroids or by nuking themselves up, to save consciousness.

Dinosaurs didn't have space force to save them from killer asteroids or from the aftermath of asteroid collision.

These are exciting times though. SpaceX is going to send astronauts for the first time on May 27, 2020. They are also Starship to send humans to the Moon and Mars by 2030.