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December/Jan 2007
Howdy Folks!
Well, it's coming to that time of the year when we can expect the cold
and snow. 2007 has been great; we had exciting public programs,
the Friendly House "Starry Nights" program was a success, we
acquired a StarLab portable planetarium and an awesome time at Hidden
Hollow '07.
The public events are now over for 2007, but...there's always
observing! Yes, we do get some clear skies during the cold
months. In "honor" of the upcoming cold & winter (it
doesn't start until later this month), I thought an article on dressing
for the winter might be in order. So, "plow through" the rest of
the M111 to find the article.
Then there was the Christmas meeting (Dec 2nd) and elections.
Want to find out who was elected where? You guessed it, you
gotta read further into the M111... And the initial discussion about
Hidden Hollow '08. And remember, January's RAS meeting is at the
Bob Evans at I-71 and Ste Rt 13. Don't forget to be there,
because we have plans to make!
Happy Holidays!
Barb Hubal\
PS Hidden Hollow '08 is Coming! The dates are May
2nd-4th. Get ready to plan & organize!
And, just a reminder, the observatory had some visitors from Pana, Illinois. Neil
Maron and some of his family visited Warren Rupp on in October.
Want to see his pictures? Check out his website at
http://neil.maron.googlepages.com/mypicturesofwarrenruppobservatory .
Spaceweather.com reported on 24 Oct 07 that astronomers in Japan, Persia and Europe reported that Comet 17P/Holmes was undergoing a spectacular eruption. The comet was 17th magnitude, until the 23rd of October. Then it spectacularly (and unexpectedly) brightened to a 2.5 magnitude fuzzy ball in the constellation Perseus. By the 28th, it was larger than the planet Jupiter. It is visible to the naked eye, and looks like a roughly spherical yellow core with a dimmer, greenish outer core. As of Oct. 31st, no tail has been seen.
What would make a comet explode in this fashion? Actually, a better question is, what would make a comet explode twice in this fashion? This is the second time Comet 17P/Holmes has erupted. The first was in 1892, an outburst that led to the comet's discovery by British astronomer Edwin Holmes.
No one quite knows why it exploded. The answer may be sinkholes. There is growing evidence that some comets and asteroids may have a porous internal structure akin to Swiss cheese. Possibly one of the "holes" suddenly collapsed, exposing many square kilometers of fresh cometary ice to sunlight for the first time. A flurry of sublimation would ensue with mega-jets of dusty gas emerging from the sinkhole to create a cloud around the comet much as we see now.
Because no one can see the comet's nucleus--it is small, far away and hidden inside a Jupiter-sized debris cloud--this "explanation" is no more than conjecture. The true events at the core of Comet Holmes remain unknown.
- information and photos taken from http://www.spaceweather.com (Oct 24-Nov14th)
*******************
11/14/07 Update
Wow! The comet's really moved. It's now very close to Alpha Persei (also known as Mirfak or Algenib)- both could be seen in the club's 8" dob using a 40mm eyepiece. The comet's nucleus is much more diffuse now, and a tail is beginning to form, although it appears short and almost as wide as the comet's nucleus.
**********************************************************
11/19/07 Update
Well, the comet is still a great target for binoculars (whenever the clouds permit viewing, which isn't often in November). Holmes has faded relatively little in terms of astronomers' brightness scale, where it now hovers near magnitude 3. But its light now spreads over a larger area, so its apparent brightness has declined substantially.
Check out more about the comet at astronomy.com: click here!
Winter
has a beautiful sky (when it's not cloudy) and low humidity - a recipe
for good observing. But it can also be bitterly cold - especially
since observing tends to be a rather sedentary activity. Yet
observing can be done comfortably, if you dress for the weather.
Let's review some common tips for warm winter dressing.
Wear
layered clothing that's loose-fitting. Loose clothing traps air
inside, which helps insulate you from the cold. In extreme cold,
be sure
to protect all uncovered skin. However, the most common mistakes people make are wearing layers of cotton
on top, tight-fitting jeans below, and shoes that leave their ankles exposed
causing cold feet. Layers are important, but they must be the right layers, made
out of the right fabric.
In cold weather, you should never wear cotton next to your skin. That
goes for ALL underwear & socks! The reason? Cotton doesn't hold in heat
very well even when dry and it absorbs moisture, so once it's damp, the
moisture conducts heat right through it. If there is any wind, you'll feel a
chill, making it worse. Once it's wet, it takes forever to dry. So the layer
right next to your skin should be a synthetic fabric, such as a treated
polyester. Since polyester is incapable of absorbing moisture, it won't lose its
insulating properties when wet and will dry rapidly.
There actually is a natural fabric that will work next to your skin and
women have known about it for a long time: Silk. It's extremely . . . well
silky, won't absorb moisture and allows other layers to easily slide over it.
It also feels great next to your skin. The warmth it provides given its weight
is amazing.
So the first layer next to
your naked body should be underwear made of either treated poly or silk. The
second layer should be a long sleeve top, bottoms, sock liners for your feet
& glove liners for your hands. These last two items should be lightweight
to make room for additional layers. If you get cold easily, put on a short sleeve
crew neck poly shirt on top of this layer. This will help keep your chest &
back warm. The next layer could be a heavier layer of polyester, or a poly
turtleneck, depending on the weather and your own comfort level.
Thinking wool for that outer layer? Think again. Wool is a much better insulator than cotton, but
wool will absorb moisture and when it does, it will lose all of
its insulating ability. It also takes forever to dry so don't allow it to get
wet. idea for the outer layer on top is a
fuzzy fleece pullover or jacket. They also have pockets. If it is made of polyester, it won't absorb
moisture and will trap heat very well. Look for one that has large enough pockets on
both sides to hold your hands with gloves on. If
you get cold easily, wear a poly or down vest underneath this layer.
The outer layer can also be a nylon down jacket or a full length coat
that extends below your rump. Realize that even down will lose it's
insulating
ability when wet or compressed too much. It needs room to puff out.
Finally keep in mind that this
outer layer will need to be large enough to accommodate the layers beneath. You
need space for trapped air in these layers and so you can move.
Next, let's talk about your legs. If you layer up your chest well, but
only wear cotton jeans, you'll freeze. Why? First, your rump & legs
have more surface area than your trunk. Two, cotton doesn't insulate very well
and the warm blood that leaves your core will loose its heat as it travels down
your legs to your feet and back again, where your core has to warm it up again.
You'll be alright for awhile, then you'll start to get cold and then you'll
start to shiver. Third, once you reach this point, your body will constrict the
blood vessels going to your legs & feet to maintain your core temperature,
making the situation worse. Fourth, jeans don't block the wind.
So what to do? Silk bottoms under jeans is a first step. Adding poly bottoms between the silk
ones and your jeans is another. Wearing flannel lined jeans is another option.
Get them roomy enough so you can layer underneath them if need be. Or forget
jeans altogether and go with nylon insulated bib overalls, like those you ski
in. These have the advantage of covering your lower back when you sit or bend
over, so that no skin is exposed. Or you can wear sweat bottoms made of fuzzy
polyester and wear plastic or nylon raingear or snowpants over them. This
combination works well because it allows you to move, it traps warm air, the
nylon shell keeps wind from cooling you off, and the suspenders don't constrict
your waist like a belt does. With your rump & legs covered like this,
you'll be very comfortable for long periods of time and your feet will stay
warm.
Now about your feet... Protect them well; if they're cold, the rest of you will be cold too! How to keep your feet warm? Layer them. First a very light long sock made of either
polyester or silk. Next, a heavier sock that will cover your calves. Next, you need a shoe that is large enough to let
you wiggle your toes and trap heat. If your shoes are too small for these
layers, you'll compress the insulation making it less effective and your toes
will be jammed together, so they'll get cold. Insulated after-ski boots work
well as they also cover your ankles. Regular shoes leave your ankles exposed
and you'll loose critical heat. Plus cold air always sinks and that's where
your feet are. Whatever boots you decide on, don't over tighten them. Also, in extreme cold, hard ground seems to rise up through your boots
if you stand there for long periods. Even a simple throw rug or doormat can
help insulate you from the cold ground.
Let's move on up to your
hands. Layering works well here also. Start with a lightweight poly or silk
glove liner, then an intermediate glove if you need it and finally a ski glove.
Don't make the mistake of trying to cram your hand with these additional layers
on into a glove that's too small. Your hands will be cold and uncomfortable and
then you will. You need airspace around your fingers to keep them warm. Since
we have to focus, change eyepieces, turn on flashlights and such, many will
want to use gloves. But if your hands get cold easily, insulated mittens with a
nylon shell over them are warmer because your fingers are all together and
mittens have less surface area by far exposed to the cold than gloves. Another
tip for keeping your hands (and feet) warm is to apply a little greaseless
lotion to them first. It'll act as an additional insulation layer. Matter of
fact, you can do this to your entire body (including your back) if you get cold
easily. A little goes a long way here; you don't want to be sticky.
Finally, we come to your neck & head. A polar fleece neck gaitor (it
looks like a short, wide tube that's open on both ends) will cover your neck
and prevent heat loss, which can be substantial in this area of your body. If
you wear a turtleneck, pull it up all the way under your chin as a first layer
over your neck then put the neck gaitor over it. For your head, there are many
choices. If you get cold easily, you should wear a silk or poly balaclava then
a ski cap or the hood from your jacket (if it has one) over it. A balaclava
looks like a sock, sized for your head, with a oval hole in the side for your
eyes. It covers your head, ears, nose, mouth and neck. Even a lightweight one
will keep you very warm
Think you're overdressed? Remember, if you're going out on a walk, you can get away with less, because your muscles will generate heat as you exercise. For non-aerobic activities, you might have to add a layer here or there. And a few last things to remember:
As you may already know, RAS is a member of the Astronomical League. The League's Observing Clubs offer encouragement and certificates of accomplishment for demonstrating observing skills with a variety of instruments and objects. These include the Messier Club, Binocular Messier Club and the Herschel 400 Club, the Deep Sky Binocular Club, the Southern Skies Binocular Club, the Meteor Club, the Double Star Club, Lunar Club, Globular Cluster Club, Constellation Hunter Club, Southern Sky Telescopic Club and the newly formed Open Cluster, Planetary Nebula, Lunar II and Outreach Clubs.
Hidden Hollow Star Party was October 12-14th 2007. We had some of the finest guest speakers available - Phil Harrington, Terry Mann, Brent Archinal, Jason Shinn, Tom Whiting, Phil Creed and Ron Ravenberg. It was a bit of a cool weekend (lows in the lower forties...), but well worth the chill...because the convention was hot!
Fortunately, we had a good group of volunteers on Thursday and setup went quickly. There were trash cans to put out, a food vendor to locate, furniture to move and rearrange, a speaker's auditorium to set up, and registration packages to prepare.
WANT TO SEE MORE PICTURES?? CLICK HERE!
BD Hubal 8-Dec-2007
Updated: 4-Jan-2008