There are two ways of looking at the event that occurred on April 27. The positive way and the pessimistic way. Observatories all over the world are continually surveilling the outer space for possible dangers coming from asteroids and comets that wander like nomads and could intersect their trajectories with that of our planet’s. To represent a danger, the asteroid would have to have a particular dimension and path.
The speed matters too, but if it is big enough and the trajectory intersects Earth’s, it doesn’t matter if they travel at almost 13,000 miles per hour or 53,000 miles per hour. It’s not like we would give it a fine for speed, or we would suspend its driver’s license.
In the last two weeks, the sky agenda was pretty busy with asteroids traveling close to Earth. March 24, 24, 26, 28, and 29, six asteroids were to get as close to Earth as 1 million miles. The largest of them was 1,280 feet wide. But the distance was considered to be pretty close. The most soothing thing of all was that knowing that scientists know when asteroids get close.
The event on March 27 had torn this feeling apart. On the night on March 26, one of the Pan-STARRS survey telescopes reported an unknown object wondering in space. The next night, March 27, NASA’s Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) in Hawaii said that the unknown object is an asteroid. An unobserved seventh asteroid temporarily named P20ZIf8.
A close asteroid took scientists by surprise
An hour later, observatories from China and Germany responded to Pan-STARRS’ alert with worrying information: the asteroid had a 10% probability of hitting Earth.
On April 28, at about 18:49:40 UTC (20:49:40 CEST), P20ZIf8 which became 2020 HS7, came as close to Earth’s center as 42,745 km (26,554 miles). This puts 2020 HS7 in the top 50 closest meteorites that have ever approached Earth.
Luckily, the asteroid wasn’t more prominent than a few meters, so chances are it would’ve been torn apart at the entrance in the atmosphere had it been intersecting its trajectory with Earth’s. The positive way to look at the event is to look at the way scientists concerted their efforts to respond so rapidly to the surprise. The not so optimistic way starts with the little question, “how did they miss it?”.