Interesting Newsletter on NEOs

[bigmasterdrago]

I just ran across this.

The ESA SSA-NEO Coordination Centre has released the December newsletter summarizing the most relevant data and events on asteroids and comets approaching the orbit of the Earth.

https://neo.ssa.esa.int/-/latest-newsletter

[PMSchu]

Thanks BMD, very cool info.

This is great:

Current NEO statistics 
The usual large number of discoveries during the month of November brought the total count of known NEOs above 27 500. 
• Known NEOs: 27 566 asteroids and 117 comets 
• NEOs in risk list*: 1278 
• Number of NEOs designated during last month: 377 
• NEOs discovered since 1 January 2021: 2874

That's a lot of NEOs!

Looks like your chances of observing fast movers is increasing rapidly  /

Phil S.

[bigmasterdrago]

Yes, it's a wealth of info. The counts change so fast that it can become outdated in just a few days. The database at Lowell has 27,673 NEOs listed in the current download. The MPC list contains 27,696 NEOs while JPL has 24,744 in the unnumbered catalog and 2,969 in the numbered (mature, known orbits) catalog. These numbers are from downloads just now. Fun Stuff!!

---

Another interesting data set are the Potentially Hazardous (PHA). MPC has the number at 2,240 showing the most recent confirmed orbit as 2017 YT5 which has the next close approach in August 2084. I feel confident that there are recent discoveries that simply do not have a significant number of observations to confirm a good orbit. If you bring up the list of PHAs in the JPL Unnumbered (unconfirmed orbits), You'll see the recent find as either 2021 WD or 6344 P-L. Could not find much on them since the Minor Planet Center seems to be having web issues at the moment. 2021 WD had a 14LD pass in July 1947 and then another one a month ago at 65LD. I ran it out a few hundred years and the closest pass I see is 9.6LD in July 2232. It's a high inclination (9°) Apollo PHA so not many chances of close encounters. Maybe in thousands of years, but I'll let JPL deal with that.

[bigmasterdrago]

I decided to run it out 5000 years with a minimum distance of 0.01AU and found no hits. Not sure what JPL/Horizons has for close approach data as all I can find is at https://ssd.jpl.nasa.gov/tools/sbdb_look...D&view=OPC

You might think that if it is classed as an Apollo/PHA, they would at least have something definitive in the table.

[ledge1962]

Thanks BMD. There is a lot of info on that site. Some good tools too.