The Near Earth Object Thread

[James Kerman]

Asteroid 2019 CB2 will pass the Earth at 1.04 million kilometers at 1.20am GMT (UTC) on Sunday, February 10.

Image captured from the interactive JPL Solar System Dynamics Small Body Database Browser.

Asteroid 2019 CB2, classed as on “Earth Close Approach”, will breach speeds of nearly 29,125mph or 13.02km per second as it passes our planet and the flyby comes just five days after NASA’s Jet Propulsion Laboratory first observed the rock on February 2. 

As of February 5, 2019, NASA has discovered a total of 19,585 Near-Earth Asteroids (NEAs).  More than 8,500 of these objects measure more 460ft (140m) in diameter – these are additionally dubbed “Potentially Hazardous Asteroids”.  Another 897 of the 19,000 asteroids measure a cataclysmic 3,289ft (one kilometer) or more across.  Asteroid 2019 CB2 is a much smaller object estimated to be in the range of 59ft to 127.9ft (18m to 39m) in diameter.

 

[Scotius]

So, a bunch of potential Chelyabinsks, and a handful of 'city killers' around our neighbourhood. But we can take it - as long as really bad ones, the 'dinosaur killers' stay well away from Earth.

[StrandedonEarth]

I’d like to know how many of them are metallic...

[Scotius]

I wonder... what if we send a bunch of CubeSats equipped with simple instruments (magnetometer perhaps?) to NEO's to check their metallicity? Just to identify the ones with highest concentration of elements we are interested in. Actually, we would only need to precisely measure the size of the obiect, do a fly-by and use changes in trajectory of the probe to pinpoint the mass of the asteroid in question. If its mass would turn out to be higher than a big chunk of rock should have, we could quite safely assume there is a lot of dense metals hidden inside. MarCo probes have proven that CubeSat sized probes are viable, especially near Sun where their solar panels work well.

[kerbiloid]

9 hours ago, StrandedonEarth said:

I’d like to know how many of them are metallic...

+1

Spoiler

 

 

[Green Baron]

The are only very few new discoveries of large NEOs (>1km), most of them are known and tracked by now. Small and midrange objects still show up every now and then.

Impact risk table from jpl https://cneos.jpl.nasa.gov/sentry/

Though some objects will come pretty close in the coming decades/centuries, none has made it on the watch lists for a longer time.

[tater]

At some point these will be considered the resources they are. This is something enabled by much lower cost to orbit, and for larger volumes/masses.

 

[kerbiloid]

Here we get a new method to recognize the alien civilization.

A strange lack of potentially hazardous asteroids around an Earth-like planet.

They've cannibalized them all.