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The 'Rarity' Column on the CNEOS website
Hi MP Hunters,

I just noticed the 'Rarity' column on the JPL's CNEOS website here:

NEO Earth Close Approaches (

Here's the description of 'Rarity': 

A measure of how infrequent the Earth close approach is for asteroids of the same size and larger: 0 means an average frequency of 100 per year, i.e., roughly every few days or less, 1 corresponds to roughly once a month, 2 to roughly once a year, 3 to roughly once a decade, etc. 'n/a' means that a frequency estimate is not available. See note for details.

This is the link from the Note:

It seems like we're fortunate to have several '1's & '2's in May & June.

This is a neat concept. The article describing the method lists the pass of Apophis as a 6.

Phil S.
Here's a new article about the close approach of (99942) Apophis in 2029:

Asteroid Apophis to be Accompanied by ESA's Ramses Mission During Close Earth Flyby in 2029 - Whatfinger News Summary

It seems like they need to revise their definitions of 'Rarity', though. A 'Rarity'=3 was supposed to happen `once per decade and we just had 2 'Rarity'=3 events in 2 days at the end of June 2024. Maybe since the rate of discovery is so much higher and the number of NEOs exceeds 35,000 now, the probability of higher values of 'Rarity' has increased.

A 6 is still crazy high though.

Glad it's going to miss,

Phil S.

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