Near Earth Asteroids

[steve_bank]

Distance to mo9n about 0.238900 million miles. Asteroid 1.3 million miles.

‘Near-Earth’ asteroid twice as big as Empire State Building to pass by Tuesday; how to track, view it

An asteroid classified by NASA as a “Near-Earth object” will make its closest approach to our planet for the next 200 years on Tuesday. The asteroid, known as 7482 (1994 PC1), is set to…

ktla.com

An asteroid classified by NASA as a “Near-Earth object” will make its closest approach to our planet for the next 200 years on Tuesday.


The asteroid, known as 7482 (1994 PC1), is set to fly by the planet at 1:51 p.m. PT, traveling at a speed of about 43,754 mph, according to NASA.


“Near-Earth #asteroid 1994 PC1 (~1 km wide) is very well known and has been studied for decades by our #PlanetaryDefense experts,” the space agency tweeted last week. “Rest assured, 1994 PC1 will safely fly past our planet 1.2 million miles away.”

Asteroid twice the size of Empire State Building passes close to Earth

Space rock will come within 1.2 million miles of planet, experts say

www.independent.co.uk

A “potentially hazardous” asteroid twice the size of Empire State Building passed close to Earth on Tuesday, scientists said.

The huge asteroid, which is estimated to be a kilometre wide, flew past Earth at around 4.51pm ET (9.51pm GMT) , according to NASA.


The rock, which is called 7482 (1994 PC1), was passing within 1.2 million miles of our planet, moving at 47,344 miles per hour, says NASA’s Center for Near Earth Object Studies, which tracks objects that could collide with the planet.

Asteroid Watch

www.jpl.nasa.gov

Asteroid Watch: Keeping an Eye on Near-Earth Objects​

Managed for NASA at the Jet Propulsion Laboratory, the Center for Near Earth Object Studies (CNEOS) accurately characterizes the orbits of all known near-Earth objects, predicts their close approaches with Earth, and makes comprehensive impact hazard assessments in support of the agency’s Planetary Defense Coordination Office at NASA Headquarters in Washington.
Near-Earth objects are asteroids and comets with orbits that bring them to within 120 million miles (195 million kilometers) of the Sun, which means they can circulate through the Earth’s orbital neighborhood. Most near-Earth objects are asteroids that range in size from about 10 feet (a few meters) to nearly 25 miles (40 kilometers) across.
The orbit of each object is computed by finding the elliptical path through space that best fits all the available observations, which often span many orbits over many years or decades. As more observations are made, the accuracy of an object's orbit improves dramatically, and it becomes possible to predict where an object will be years or even decades into the future – and whether it could come close to Earth.

recent

NEO Earth Close Approaches

NASA's Near-Earth Object (NEO) web-site. Data related to Earth impact risk, close-approaches, and much more.

cneos.jpl.nasa.gov

 

[Swammerdami]

Clicking the link I see an asteroid ("2021 AE") scheduled for a fly-by Dec 28, 2022 at a likely distance of 16.47 LD but a minimum possible distance of 0.01 LD. That's just 4000 km. (Or, is 0.01 LD a euphemism for zero in their accounting?) The diameter is shown as 17m-39m.

Is that really an asteroid, or is it instead some anomalous report? Google (or rather the lack of any hits) suggests that whatever "2021 AE" is, nobody finds it interesting. (The 2nd smallest minimum distance over the next 12 months is "2018 WH" at 0.38 LD.)

I suppose that even a direct hit by a 39m asteroid would be no big deal (except to those near the impact). How big does an asteroid need to be for collision to be worrisome?

 

[steve_bank]

Large asteroids have passed closer than the moon. I expect NASA is absolutely serious about the reporting. Professional reputaions are involved.

I couldn't find it, there is a real time Earth crossing tracker online.