Subj:	Asteroid 2001 HL31
Date:	5/8/01 10:04:58 PM Pacific Daylight Time
From:    tedwards@tcia.net (Tim Edwards)

Below is some info regarding Asteroid 2001 HL31, which is presently passing the South
Pole at about 30, 200 miles (the Moon is approx 240,000 miles away!). I don't want to
alarm anyone, just thought it was a very interesting discussion on the MPML and very
close call at only 30,000 miles!

Although, the 30,200 is a figure from an amatuer astronomer on the MPML, I doubt the
NEODys, NASA, nor any other public agency would post such a 'close call' on their
site.

more below:


[from the MPML]

Subject: (MPML} RE: Kansas Chatter, 2001HL31
Date: Tue, 8 May 2001 23:12:56 -0400

> > 2001 HL31
> >
> > 2001 05 10 00   11 19.27   -85 57.8   0.051  1.028  109.7  67.6
>  16.1 -517.64  -16.71
> >
> > At 517 arc sec per minute that object will be humming right outside
> our atmosphere almost at 0.0003248 AU!
> >
> > 649 helped confirm this one and has already followed it once.
>
> NEODyS and the MPC aren't currently showing quite that close of an
> approach, ...

>NEODyS shows an MOID of 0.04966 AU. Is that consistent with the apparent
motion numbers? 0.0003248 AU is only 30,200 mi (48,600 km). 2001HL31's
absolute magnitude of H=19.786 corresponds to a diameter of roughly
350-600m, depending on assumed albedo. Did we just miss a globally
consequential impact by a mere 30,000 miles? (!) [I'm probably
"over-sensitive" at the moment...I just finished reading Ed Vega's book (he
>said with a shudder)]

[name withheld]


also:

Subject: {MPML} some chatter in Kansas
Date: Tue, 08 May 2001 22:18:35 -0400

> Here is an amazing opportunity coming up tomorrow night:
>
> 2001 HL31
>
> 2001 05 10 00   11 19.27   -85 57.8   0.051  1.028  109.7  67.6
16.1 -517.64  -16.71
>
> At 517 arc sec per minute that object will be humming right outside
our atmosphere almost at 0.0003248 AU!!!!!!!!!!!!!
>
> 649 helped confirm this one and has already followed it once.

NEODyS and the MPC aren't currently showing quite that close of an
approach, but yeah, to think that I saw it less than a week ago, and
tonight it's flying straight under the south pole!  What else is out
there?

-----

Subject: {MPML} 2001 HL31: not 0.0003248 AU
Date: Wed, 9 May 2001 00:00:50 -0400 (EDT)

>I just cut and pasted that 0.0003248 AU right off of the Spaceguard Central
>Node.  I assume it is correct.  It has not happened yet.  It will be tomorrow
> night.  Southern hemisphere observers will have the best seats for this one.

>2001 HL31's closest approach will be 0.051 AU at this apparition.  The
>SgCN figure must refer to something else than the current close approach
>distance.

[name withheld]

-----


NASA has not posted this one at: http://www.spaceweather.com , and the NEODys site
posts contradictory information here:
http://newton.dm.unipi.it/cgi-bin/neodys/neoibo?objects:2001HL31;main

Additionally, the Orbits calculator has no reference to HL31 here:
http://neo.jpl.nasa.gov/orbits

Looks like they're keeping this one quiet.

Anyone know anything about this 'fly-by'?

Tim



--
*So much to learn and so little time, will we ever find the truth?*

DreamScape
http://timledwards.users.50megs.com/dreamscape.htm