[meteorite-list] Toutatis smasher and Vesta

From: MexicoDoug_at_aol.com <MexicoDoug_at_meteoritecentral.com>
Date: Wed Sep 15 15:28:30 2004
Message-ID: <4E2199B3.3CA72058.0BFED528_at_aol.com>

The sky is being invaded by asteroids this month. Only
instead of buying tokens to destroy them in a video game, you
just need a good pair of eyes or pair of binoculars, and clear
skies.

Here's a personal update on Vesta and some info on Toutatis
which you can soon might see in a telescope (or a microscope),
or binoculars in Microscopium:), the constellation that is.
It then passes into Telescopium so take your pick. We won't
get another chance to see such a small space rock under the
microscope, or anywhere else, except in our meteorite
collections, probably for the rest of our lives, let alone
with a telescope as well. Funny? For some of us I hope. So
read on if this sounds related enough to your passion, as you
hold a piece of Vesta in your hands...

Sept. 13-14-15
Everything seemed wrong, but I was determined to see Vesta for
the second time during this opposition. The night before,
September 13 I had seen it for the first time, through 16X
consumer binoculars under reasonably dark skies a bit out of
town, after twisting the arm of my own Vestal Virgin to
accompany me and keep me alert as we drove. (Did you know
that the only high priestesses in Imperial Rome were the
(max.) of 6 Vestal Virgins, whose responsibility was to keep
the Vesta temple flame burning and be examples of good morals.)

But tonight by my own point of view was special. Vesta at
around 3:00 AM would pass less than a quarter of a degree from
the bright star Omega-2 Aquarii (mag. 4.5) - an arc distance
of only about 15 arc-minutes, the same arclength as half the
diameter of the moon.

Wrong because I was on the top of my apartment building in the
middle of the second or third largest metropolitan area in
Mexico, amid sodium vapor lamps and a barrage of light
pollutants from the densely inhabited neighborhood, in a city
in love with light where only half of the electricity is
actually charged to residents. The limiting naked-eye
magnitude was an embarrassing 2.3, terrible by nearly all
standards. Well, almost everything was not promising, but it
was new Moon time, and the sky was basically clear and as dark
as it get hereabouts ... but then there was that diffuse cloud
to reckon with, patching the octant of the sky over Aquarius,
where Vesta was hidden from sight.

It was somewhat of an anticlimax, as the weekend before I had
traveled two states and several hundred kilometers to be under
dark skies to observe Vesta on September 11, with absolutely
dismal results: the perpetually clear desert skies managed to
maintain a cloud cover all night.

So here I was, on September 15 at 3:00 AM, tire from all the
recent travels and overnighters, and praying to the goddess of
the hearth that the clouds would disappear and give me a view
of the third largest confirmed meteorite parent body in the
Solar System. So I set up my camera, and by 3:05 a slight
hole opened up and the very bright star Formalhaut peeked
out. Today I only had my five power opera glasses, but
quickly focused upwards to find the somewhat dimmer Aquarian
stars I refer to as the "reflected curves," six peer stars
that with a little imagination appear to be bilaterally
symmetrical reflected smooth curves (86, 89, 88 and 101, 99,
98 Aqarii), all from 3.7 to 4.7 magnitude. As I savored the
moment in anticipation, the entire cloud almost mysteriously
began to vanish, and their was the "Striking Cobra" in
Aquarius (103, 104, 106, 107, 108 Aquarii etc.), the next
group in line, and immediately coming into view as I moved the
glasses up was Omega-2 Aquarii in the same field of view.
Could I resolve Vesta under these conditions? As my eyes
became accustomed to the dishwater blackness I made out
the "W" formed by HR 8987 (mag. 5.3), Omega-2 Aquarii (mag.
4.5), Omega-1 Aquarii (5.0), and HR 8958 (mag. 5.6). But
where was Vesta, that handsome eucrite clad diogenite speckled
quarry that so often has sent messages in a bottle to earth?
As I looked at HR 8958 wondering whether bad luck would
prevent me from seeing a half magnitude less bright Vesta, it
was unquestionable clear: look at 8958 and Vesta becomes
visible, then look at 8987, and there again was my goal, but
look right at Vesta or Omega-2 and where was Vesta. Well,
astronomers know this "averted vision" allows one to see
dimmer objects in the eyepiece - not looking directly at the
goal.

Not satisfied with an averted look I snapped the trigger of my
camera for a 30 second exposure wondering if the glowing
ribbons of the cloud and pervasive light soup would wash the
photo out. And as the exposure was in progress, I watched
through the opera glasses and concentrated very hard on Omega-
2 and soon Vesta, too, was visible. So I looked directly at
it and could finally behold her. Vesta looked somewhat bluish
as I imagined that this was over 203 million kilometers away
(just 1.37 times the Earth-Sun distance, not bad for an object
between Mars and Jupiter!). As soon as the exposure finished,
I got ready for a second, astronomical favors were no longer
being granted, and as quickly as the cloud had disappeared, a
new one materialized over a broad swath of sky on the mountain
beside my field of view and immediately covered nearly one
full quadrant. A half hour later, the situation was much
worse, and I decided to go to sleep.

Drifting off to sleep, I was already making plans for one more
date with Vesta, and then a trip to darker skies to see
Toutatis on September 27 from 8:30 PM to 9:00 PM, the only
real possibility from here, as it is low and sets early in the
sky and the Harvest Moon will rise at 8:45 PM and interfere
during all other opportunities. Toutatis is a tumbling
dumbbell shaped, three-kilometer along its great axis asteroid
that will undoubtedly be the smallest "natural" astronomical
mass I might ever see in-situ, with my own humble equipment in
my lifetime, ignoring for a moment the potential for small
undiscovered gaseous comets destined for our neighborhood, as
it is the near earth object that most closely will visit the
earth in the next 60 years. Toutatis will arrive about 1.5
million miles away. Well, no doubt we will be hearing about
Armageddon again from some even though our own gigantic Moon
is one-fourth that distance away every day. Well, I guess the
predictability is somewhat comforting to those who worry about
these things. Vesta was good practice this time around, as
Toutatis will be 9th magnitude. That will call for the 16X
binoculars again and much darker skies - and then be at the
limit. Hmmm, maybe a camp out to dark sky strewn field, date
at 8:00 PM sharp, don't be late, with a mountain hiding the
Moonrise, can help contemplate what holding a piece of
Toutatis in my hand would be like, or to imagine the scene
with such a tiny but would-be "deadly" space rock impacted...
Saludos, Doug
Received on Wed 15 Sep 2004 03:28:23 PM PDT