Earth to have close brush with comet

Originally posted by cmdrkeenkid

(...) The computer isn't neccessary at all, if you have a good set of charts and a book teaching you how to use a scope. (A couple other things I would highly reccommend picking up, even if you go the computer route.)

But isn't there a warning going around that computerized telescopes for amateurs (with so-called "GO TO capability", that points the thing at any object you want to see) can be treacherous?!! If the automatic device breaks down, the telescope turns into an expensive piece of useless hardware and suddenly you find yourself there, on a chilly night, in some faraway field, with nothing to do except count the stars.
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Originally posted by Macrento
But isn't there a warning going around that computerized telescopes for amateurs (with so-called "GO TO capability", that points the thing at any object you want to see) can be treacherous?!! If the automatic device breaks down, the telescope turns into an expensive piece of useless hardware and suddenly you find yourself there, on a chilly night, in some faraway field, with nothing to do except count the stars.
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Yeah, it can happen. That's why I said the computer stuff isn't neccessary at all. In fact, I would reccommend not getting it with the computer at all. It's just one more thing to worry about, and with telescopes, you have a lot to worry about. ANyone who has one that gets frequent use out of it (computerized, or not) will tell you how much of a hassle the things can be sometimes!

I look at it this way. For centuries people learned the heavens without electric computers, so why do we need such a reliance on them today? The answer is: We don't. People just don't want to take the time to learn something useful.

Not only that, but experts suggest that beginners should not rush out and buy a telescope. They must spend an entire year watching the constellations with the unaided eye until both hemispheres of the nightsky are as familiar as the streets of one’s neighborhood. It’s amusing to see how the constellations, or the asterisms like the Big Dipper,TUMBLE across the sky during the night. For example, the Big Dipper will first appear to the east in a horizontal position, then, halfway across the sky, you see it standing upright, and, finally, to the west, again stretched out horizontally. As you see this, for the first time you feel you're rotating in space on the surface of the Earth, leaving behind the stars as they go by.

Meanwhile they can have some fun with the handy binoculars, watching the Moon, the tiny dipper of the Pleiades and the windows of the surrounding apartment buildings. Through a window across the street I could once see some bookshelves, and I was surprised that I was able to read the title on the spine of a thick book: BEST GHOST STORIES. It wasn’t a pair of binos, really, but a cheap little red Tasco “pirate” telescope that you stretched or shortened in order to focus on something, a plain device for the field that wouldn’t invert the image like sky telescopes do. This might be initially the best option. "For that money you cannot go wrong."

...but it's the other way around: the Big D. stretches out halfway across the sky, and you see it in a vertical position to the east and west. Sorry --it's that I'm out of practice after three years in a tiny apartment with no view. A suggestion for people holed up in "dungeons" like that one: a local college might have an observatory with a Friday-evening event that starts out with a short lecture, then people take turns looking through the big telescope, or it might have a screen with the image. Or the planetarium might bring out a few small telescopes and place them on the surrounding lawn on certain evenings, or sun scopes at midday.
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Originally posted by Macrento
Meanwhile they can have some fun with... the windows of the surrounding apartment buildings.

Just don't let that get too out of hand, as your mind may wander...

They still have all that same info up. Anyone have any idea why it hasn't bee updated yet? I would think they would know the orbit a bit better by now!

NEO Earth Close-Approaches

Object: 73P/Schwassmann-Wachmann 3-BD
Close-Approach Date: 2006-May-11 21:53 ± 11:11
Miss Distance Nominal (LD/AU): 33.7/0.0867
Miss Distance Minimum Ascending(LD/AU): 0.04/0.00010
V relative (km/s):14.79
V infinity (km/s): 14.78
N sigma: 3
H (mag): n/a

[edit on 5/10/2006 by cmdrkeenkid]

Let's face it, they just don't know. The nominal and minimum miss distances for every one of the fragments being tracked are wildly divergent. In some cases they don't even know which date they'll be passing us. This one will either be 8 million miles away at 10pm tomorrow, or it will have already smashed the crap out of us at 9am.



[edit on 5/10/2006 by mythatsabigprobe]

This quote is taken from here: anyone been following the Schwassmann-Wachmann comet

Originally posted by joepits
a few days ago the nasa site said there is a chance that this comet fragment will come as close as .0001 (about 5000 miles) AU today the 11th. in one of the tables of the data they had 11:11 as one of the statistics. is it a coincidence that this is the number a lot of people have been seeing on clocks, or is this nasa's way of giving us a wake up call that something big is going to happen.

Actually, the 11:11 is the uncertainty in when it will pass by the Earth. So they're saying it will pass by at 21:53 UT today, give your take 11 hours, 11 minutes. I think it's just a coincidence, not those at NASA warning us.

theres like 60 fragments to this comet because its been breaking up. if one hits the ocean there will be a tsunami. even if its a pretty small chunk, it will still hit because comets don't break up in the atmosphere (they travel way too fast).

Actually, a small chunk would disintegrate in the atmosphere. Comets are mainly ice, and unless it has a considerable amount of mass or is really dense, it wouldn't make it to the ground. There is possibility of a Tunguska like event though, in a comet breaking up like that.

also in the following weeks the tail of the comet will overlap earth's orbit, which will shower us in comet dust which may contain biological material or some other type of energy that is harmful to us. or the dust might make our skies permanetly dark.

Considering we're almost always passing through one comet's tail or anothers, I'd say the chances of that are pretty slim. Meteor showers are caused by the Earth passing though the tail or string of debris left behind from a comet's pass. Here's a list of meteor showers so you can see how often they just are.

[edit on 5/11/2006 by cmdrkeenkid]

You,re gonna laugh,but when i got the server down message this morning i tought you guys had got whacked by the comet.

What,s the time over in the dear old u.s of a? still wearing hardhats and a snorkel just in case? hope to see you tommorrow

btw still laughing my boobies off at the hot fudge sundae tag. naughty i know

[edit on 11-5-2006 by AGENT_T]

Originally posted by AGENT_T
What,s the time over in the dear old u.s of a? still wearing hardhats and a snorkel just in case?

hope to see you tommorrow

It's about 11:30 here on the East Coast.

btw still laughing my boobies off at the hot fudge sundae tag. naughty i know

Yeah, was that you? I just noticed that a few minutes ago, actually.

Yeah, was that you? I just noticed that a few minutes ago, actually.

You know, i kinda wish it was but i,m too much of a goody goody to break board rules.AND i,m saving points for a nice shiny new signature

oops title i mean.. hmmm. what to put????

[edit on 11-5-2006 by AGENT_T]

Originally posted by AGENT_T
i,m saving points for a nice shiny new signature

Signatures don't cost any points. Just click on Settings, then Edit Profile. Also, remember to reset your time zone because for whatever reason whenever you edit your profile it defaults back to +12:00 UT.

Anyway, we digress... Let's get back on topic.

I just noticed something a little odd. I can't seem to figure it out, so maybe it's just a large brainfart on my part. Then again...

NEO Earth Close-Approaches

Close-Approach Date: Date and time (TDB) of closest Earth approach distance. "Nominal Date" is given to appropriate precision. The 3-sigma uncertainty in the time is given in the +/- column in days_hours:minutes format (for example, "2_15:23" is 2 days, 15 hours, 23 minutes).

Miss Distance (LD,AU): The most likely (Nominal) and minimum possible (Minimum) miss distances are given in LD (Lunar Distance) and AU. The minimum possible distance is based on the 3-sigma Earth target-plane error ellipse.

Note what I bolded. Shouldn't that be N-sigma? I just noticed it now, and what I find even more odd is that the N-sigma of 3-BD is 3!

Maybe someone can explain this, please I'm just at a loss. The only thing I can think of is that it's using the number 3 as the amount of axes involved with making the calculation, but I'm not sure if that's right.

Originally posted by cmdrkeenkid

Just don't let that get too out of hand, as your mind may wander...

As a matter of fact, there WAS some reckless eyeballing on the side, but with the naked eye, and it was quite involuntary, in a way.

A lady once appeared entirely in the buff, on a balcony that was enclosed by glass walls, much like an aquarium. All she wore was a towel wrapped around the head like a glorious turban. She was wonderfully unconcerned. There was no time to go bring that little hand-held field telescope. Strike the iron while it's hot, they say. This was in broad daylight.

It must've been months later that I saw a naked couple in bed, but like through a fog. One of those gauzy curtains was in the way. She was lying face down and he was kneeling beside her and massaging her back. This was late in the night.

That was all. There was a lot more action in the heavens, and on the cordless phone.

I once tripped over the electric cord with the adapter, the one that continually recharges the battery, yanking it off the wall socket, and all of a sudden the tone was gone and I was listening to a funny conversation, loud & clear. A serendipitous discovery: just unplug the adapter so the tone won't interfere, and enjoy.

Also, the telephone line was dead. I'd picked up the phone to see if it was out of order because the dial-up Internet connection didn't seem to be working. This means I was picking up the chat entirely through the ether. (Big hint.)

In the following weeks, an additional finding: nearly all conversations are boring. Even so, the good ones are really good.

So I went out and bought myself a device they call The Watergate. This would allow me to tape record, publish and attain gold and glory. Tragically, I was unable to make it work. The sound volume of the recordings was so weak that they were inaudible. Any helpful tips, please, anyone?




[edit on 11-5-2006 by Macrento]

[edit on 11-5-2006 by Macrento]

Originally posted by cmdrkeenkid
Maybe someone can explain this, please I'm just at a loss. The only thing I can think of is that it's using the number 3 as the amount of axes involved with making the calculation, but I'm not sure if that's right.

I am not sure about the N-Sigma number or why it is 3 for the object, but in statistics, 3- sigma is stating what the confidence level of the interval is. Sigma is the standard deviation from the mean value and 3 sigma means that they are 99.7% or very close to 100% confident that the close approach will occur within the given interval of 11 hours and 11 minutes. So I interpret this as meaning the close approach will occur most likely at 21:53 today, around 9:53 PM EST, but can actually occur anytime between 10:42 AM this morning, and 9:04 AM tomorrow morning, with 100% certainty. It does not mean it is certain to hit us, just when the close approach will occur.

Just as a reference, if they stated an uncertainty 2-Sigma the confidence level would be 95.6% and 1 sigma would be 68.2% confidence level and the time interval would have been less than 11:11.

Relationship between Uncertainty and Confidence Level


So if one lunar distance is 238,857 miles, then the minimum distance of .04 LD is equal to 9554 miles. That’s less than 10,000 miles. The diameter of the Earth is about 8,000 miles, so the minimum distance is just over the diameter of the planet. Is that right?

That is friggin close!

I hope they have just as high confidence on the minimum distance than they do on the time.

As far as I understand it, even if this comet does hit us, it's to small to do any real damage. It most certainly won't be anything comparable to a worldwide extinction event. Even if the comet hadn't fractured, and hit the earth in it complete form, it wouldn't be big enough to wipe out life on earth. So a fractured piece probabyl won't survive the trip through the atmosphere.

My guess would be, even if it were to hit the earth, it would most likely explode in the atmosphere, probably causing some local damage similar to what happened in Russia in 1908. But that's even assuming it hits us, which it most likely won't.

Still, I hope this wakes things up in our government, so they can start giving proper funding to the study of NEO and the prevention of a future strike that will inevitably happen. The last asteroid that passed extremely close to the earth (I forget the name of it, sorry), we did see it until three days after it had passed us. That doesn't exactly inspire confidence.

Well, 3-BD passed without incident.

Neon Haze: We told you so.

Hal9000: Thanks for the clarification!

[edit on 5/11/2006 by cmdrkeenkid]

I'm so confused. LOL! If we're in the window of potential impact time, shouldn't we have a better grasp on if it will or will not hit us?

I looked on the linked site, but couldn't find the one that's supposed to come close today; there's one tomorrow, and several on the 14th, but none for today. Is that because it's already tomorrow some places in the world?

Thanks-
Aimless

Originally posted by cmdrkeenkid
Well, 3-BD passed without incident.

That's good to hear, but I'm curious, how did you find out? Most astronomy/space sites are not even talking about how close it is. I know you work at an observatory, but you probably weren't able to see it yet. Did you hear about it from another observatory? And was anyone else concerned about how close it came?

Hal9000: Thanks for the clarification!

Glad I could help.

Originally posted by Hal9000
That's good to hear, but I'm curious, how did you find out?

It's no longer listed on the NEO Earth Close-Approaches list.

That, or they took it down because it hasn't passed yet, and it'll be impacting. But I highly doubt that.

[edit on 5/11/2006 by cmdrkeenkid]