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Those pictures look more like Rorschach tests, or my neighbor the last time she took LSD.

Sky and Telescope also has an article on the comet.

This article also points out the unfortunate fact that when the comet is at it's brightest, it will be directly on the opposite side of the sun, and impossible to observe from the Earth.

Sky and Telescope also has an article on the comet.

This article also points out the unfortunate fact that when the comet is at it's brightest, it will be directly on the opposite side of the sun, and impossible to observe from the Earth.

This formula isn't particularly one you need to test the validity for. It's just like saying that we want stars that are as close to the sun as possible, but putting that in mathematical language so that we can quantitatively compare the stars we're looking at. We obviously pick stars which are as similar to the sun as possible, because as far as we're concerned, they're the most likely to harbour intelligent life.

Now, if you really want an equation that involves handwaving, check out the Drake equation. It's useful, in that it lays out what the factors are which contribute to the number of potentially communicating civilisations are, but as soon as you try to quantify it, you run into all kinds of problems. Different places give very different answers.

85% [wired.com] of their time is required for maintenance.

Very little hard science has been done due to construction delays and retrofitting many of the parts.

The editorial in the December issue of Sky and Telescope grumbles about this. As the author put it, 30 years ago (i.e. Apollo 17) we had three guys at the Moon, making discoveries. Now we have three guys in low Earth orbit, fixing things.

Sigh.

...laura

Unfortunately, the next time Temple-Tuttle (the source of the debris that we're watching) comes through in 30 or so years, it will not be passing close enough to leave a good amount of dust in our orbital path to create the kind of storm we're treated to this year. In fact the next pass after that still won't be close enough. It won't be until 2098 before it passes within .0062 AUs (close enough to get a storm in the following year or three).

All of this information and some great viewing suggestions and times are attainable in a really good article at Sky and Telescope.

As the comet Tempel-Tuttle approaches the Sun toward a May 2031 perihelion, it will pass within 1.5 a.u. of Jupiter in August 2029. This encounter will push the comet closer to the Sun and increase the distance between Earth's orbit and the comet's to 0.0162 a.u. -- their largest separation since 1733. Such a large gulf between the two orbits may preclude any substantial meteor activity for the year 2031, and for several years thereafter, when the next cycle of Leonid storms would normally be expected.

In examining this next Leonid cycle, McNaught has found three outlying dust trails that the Earth will approach in the years 2033 and 2034. "Unfortunately," he notes, "they are probably too distant for any reasonable chance of high activity."

There will be little improvement at the comet's subsequent return in 2065, for the separation between the orbits of the comet and the Earth will have diminished only slightly to 0.0146 a.u.

In 2098 the separation of the orbits shrinks to 0.0062 a.u. And in 2131, for the first time since 1633, the comet crosses our orbital plane slightly outside the Earth's orbit at a distance of 0.0089 a.u. Not until one, or both, of these remote years can our great grandchildren expect to witness a storm of Leonid meteors.

So get out there and see the damn thing. I'm in Northern Thailand, so not much hope for me :-(

This year's Leonid shower will be the last one for a long time to come! Earth won't pass through this comet trail for quite a while. The next probable year for a Leonid shower/storm is 2098, or maybe even 2131!

See this article for explanation. The dates are on page 4.

But for this year, a great show is still expected. So if you have half an option to go outside for a while (say, Nov 19), do so!

After the Sun and Moon. Its been fascinating to watch it get brighter as they add more cylinders and panels every year.

The station is visible in the evenings about one week a month and mornings one week a month, so the orbit can wobble over the US, Russia, Europe, and Japan. Sky & Telescope (set zip code, click on almanac) shows pass times & locations, as do other websites.

If you go to the Sky and Telescope site, you can get awesome charts for locating this asteroid. These charts show all stars at least 9th magnitude in brightness. Using brand new 10x50 binoculars, I can see all 9th magnitude stars, but just barely. The asteroid is predicted to be between 9th and 10th magnitude, so it looks like I'm out of luck. BTW, I'm out in the country with very clear skies. Anyway, go to the Sky and Telescope site (cookies req), download the charts and give it a shot. OK, back to my regular programming...

... is the distinct possibility that a catastrophic asteroid collision could happen with no advance warning at all. For example, on June 17th, the near-Earth asteroid 2002 MN was discovered. This 100-meter-wide asteroid's path was such that it came within 120,000 km of Earth (inside the orbit of the Moon) -- on June 14th, three days before anyone even knew it existed! Story (complete with graphic showing what a close shave it was) is at Sky and Telescope.

In a way, the alarmist stories about 2002 NT7 are more comforting to the public than the reality of asteroids like MN 2002 that blindside us. If people really realized how little control or even knowledge that we have about such things, they would be pretty freaked.

What a bunch of useless answers. What the person obviously wanted to know is, what point on the earth was facing the asteroid when it passed a point where it could have hit us?

Based on this article, i'd make a rough estimate that it would have crossed earth's orbit path at about 0200h GMT on June 14th. So, all we need to know is what local time zone was at 1200h (sun at highest point, approximately) when it was 0200h GMT.

1200h would be 10 hours east of GMT. My handy-dandy clock tells me that GMT+10h is Brisbane, Sydney, Melbourne, etc. So it sounds like Australia was facing the asteroid at the time it passed...

Hope this answers the original poster's question...

1. Scientists are still assesing the odds on this, as far as what is something to freak about, and why isn't.
2. a number of the Near Ear Orbit tracking pages are properly showing distances not only in Astronomical Units, but also in Lunar distances. This is because for close earth passage the fractions get unweildy, and people freak out at terribly small numbers. That said, a million miles is roughly 4 lunar distances, the sun is somewhat under 400 lunar distances away, etc. It's a good yard stick because people can think with it.
3. odd factoid: since the moon is about 2,000 miles in diameter, this lets you estamate how big the earth would be in the sky if you were standing on the Moon. The Moon is smaller than the distance across of North America or the Nation of Brazil. Imagine an appropriately sized globe in the sky, and there you go.
4. This object did come kinda close. If you make the analogy of the average height of a human equals the size of the earth (5 to 6 feet), then the moon is roughly 200 feet away. In this scenario, the asteroid is roughly like a very high speed BB Pellet (or smaller) wizzing by at a distance of 30 ft or so.
5. Distance estimates I saw said about one sixth the distance of earth to the moon, about 40,000 miles (reports I saw in Sky and Telescope here, pretty diagram included)
6. You can query the Nasa Near Earth Object Database here
7. Veterans in Combat are much more non-chalant than civilians about the risks of small high speed objects in the space about them. Of course, they usually have the option to duck.

Sky and Telescope always have the best data for these kinds of questions.

They have a diagram of the ground track and a timetable giving cities and times of the event.

Sky and Telescope always have the best data for these kinds of questions.

They have a diagram of the ground track and a timetable giving cities and times of the event.

Sky and Telescope always have the best data for these kinds of questions.

They have a diagram of the ground track and a timetable giving cities and times of the event.

Taiwan, the Philippines, and New Guinea will see the eclipse at sunrise on June 11. This Sky and Telescope article has another map.

Taiwan, the Philippines, and New Guinea will see the eclipse at sunrise on June 11. This Sky and Telescope article has another map.

Diskettes transmit too much IR and provide an inferior image, according to this Sky and Telescope article by Ralph Chou, a professor of optometry. Don't fool around, get a #14 shade from a welding supply shop. They're cheap, convenient, and reliable. Mine is a 4x5-inch plate of black ceramic material that turns the Sun a lime green color. When I bought it, the guys at the shop said, "Yeah, we got a few of those left over from the last eclipse. Nobody uses 'em for welding, they're too dark!"

The abstract of the article in Science doesn't mention Mercury either. (Nosy free registration required.) I don't know where the BBC got the idea. It would be cool (hot) if it was true, but don't know who originated it. Another note about the meteorite, referring to "another Vesta," but not Mercury.

Min. req. these days for comet hunting is about a 20" or 22" obsession scope.

Until he died earlier this year, Yuji Hyakutake found comets with his 25x150 binoculars. Even then though, usually it's rewarding just tracking down and finding these things that the professionals find. Having a big telescope doesn't hurt, but it's not absolutely necessary. What really helps is keen eyesight, a certain amount of patience and experience, and an extremely good knowledge of what the sky and background stars should look like in whatever region you're looking.

Big telescopes aren't that much of a big thing, either. I know several people with 20"+ telescopes on homebuilt dobsonian mounts... and they are monster amateur telescopes, with the main significant expenses being the mirror and the time to build it. Apart from that it's just having somewhere to put it. I'm not suggesting that it's something for everyone, but it's hardly out of reach, either.

Is this really new? I don't know where I first heard it, but I know that a "big crunch" has certainly been theorized. I've always thought that it seems likely that a big crunch might cause a big bang to follow. I don't know, maybe I was assuming something.
You're right, the "big crunch" is not new. However, this way of explaining its cause is. From the article I posted earlier, The idea of a cyclic universe has been around ever since the Big Bang was first proposed in the 1930s. But no one could find a way to make the "big crunch" that ends one cycle of the universe "bounce" to become the big bang of the next.
I guffawed at first, too, until I read this better writeup.

If you look at the complexity of human beings, it's just crazy how many things have to go right to get intelligence. I mean, it took 2-3 BILLION years just to get us, and no other animal form is even close to us.
According to that logic, it took me 4 years to finish the final assignment of my final course in univeristy. What if there was a lot of time where things were happening, but not towards our development as human beings? I'm not saying that you're incorrect, but for the purposes of your final conclusion, I don't think it's valid.

When you combine that with the fact that it only takes 2-3 million years to fill a galaxy once you have intelligent life even at sub-light speeds, that means it's probably never happened before in this galaxy.
Well, our galaxy is about 150,000 light years across. It also has about 400 billion stars. Even if we had the capability to transport lots of people at the speed of light, we could only send 1 person to every ~40 stars! So it's likely that we wouldn't make physical contact with a civilization, but perhaps radio contact. Depending on how long intelligent, radio-capable civilizations last (self annihalation? extinction?) our intelligent, radio-capable years may never overlap with those of other civilizations. Perhaps many intelligent species have evolved and died in this expansion?

So given that intelligence almost never happens, and it took about 1/7th - 1/4th the age of universe for it to happen here, I think that gives evidence that we needed a hell of a lot of universe cycles to get it to happen.
Well, scientists still have no idea if (and definately no idea when) the universe will coalesce. If the cycle takes 1000 billion years, our civilization took only 1% of its lifetime to evolve to this point.

Anyways, it's a lot easier to pick apart a theory than it is to make one :) Your idea is interesting, but I just think that some of the facts aren't sound.

Sky and Telescope also covered this story, but didn't obscure it with piss-poor scientific writing like this other source did.

As an aside, the other source over simplifies things, and leaves you with the feeling that you learned nothing but marketing hype. It's target is obviously non-astronomers (or we would have read the original paper in an original journal.) Because of that, they should have explained "branes" (and other terms) with more than sound-bytes from involved physicists. Think diagrams, break-out boxes, etc.

I can sympathize with what you are trying to do, as I've tried both uses with my Nikon Coolpix 950. The short answer is both are possible, but it isn't likely to be easy to get what you want out of the setup. Once drivers are available, you should be able to use your digital camera as a webcam fairly effectively, though you may have issues with autofocus, flash, and other camera-only adjustments. For astrophotography, it isn't likely you'll be able to get worthwhile images with the Elph, but I've included a few links on how to get started.

Digial Camera Webcams

Digital cameras defintely produce a much more compelling image than a typical webcam. I have a 3Com HomeConnect (a pretty good quality webcam) and it looks just awful compared to my Nikon N950 (not just resolution, but also trueness of color, CCD noise, and sensitivity). The main limitations are that you can't usually take mini-movies or fast sequences, some key functions are often only controllable on camera (for instance auto-focus and flash), and you'll need a power cord for the camera if you don't want to drain the batteries very quickly.

The easiest way to control the camera from a linux box is with Scott Fritzinger's GPL'd gphoto program. gphoto allows basic control of a variety of cameras through serial or USB connection (and supports both interactive and commmand line modes - add a bit of perl and cron and you can do all sorts of fun things). Its still under development, however, and unfortunately doesn't currently support the Digital Elph (PowerShot S100) to my knowledge. I'm not sure how involved it would be to write a USB Elph driver for it, but you can check out the site if you feel up to it.

Digital Cameras and CCD Astrophotography

With astrophotography, you are getting into a rather specialized and involved use of CCD devices and generally speaking, it takes a good bit of expertise and dollars to get good results. You don't mention what you are looking to capture or what existing equipment you have, so I'll point out some of the basics and you can research further from these. FWIW, I'm not by any means an expert here, but I've been looking to jump in, so I'm seeing the same issues.

While there are limited exceptions, CCD astrophotography generally requires the use of specialized equipment. Your Canon Digital Elph doesn't have the required sensitivity (its equivalent to ISO 100 film), ability to take long exposures, long and fast enough lenses, or adapters for telescope mounting. While its possible to use a barn door tracker or equitorial tracking camera mount with the Elph, the results aren't likely to be worth the effort.

If you really get interested in astrophotography, you'll probably want to pony up for a specialized system like those built by Celestron and SBIG. These are highly sensitive, small array CCD cameras with specialized cooling and software for high gain operation. Add a high quality telescope, equitorial tracking mount, and related accessories, and you are talking about no small dollar commitment. Also, you'll need a lot of time and patience to find and capture accurately really good photos. I'd like to try CCD astrophotography out, but will be playing with 35mm (add a T mount and a Meade ETX and you can get started for under $1000) until I decide I'm really committed and move to a less light polluted neighborhood.

Sky & Telescope has a pretty good guide on where to start. Some good introductions to astrophotgraphy are:

• Sky and Telescope Imaging Resources
• Amateur Astrophotography links
• CCD Astrophotgraphy (annoying sounds)
• Santa Barbara Imaging Group (SBIG), a leading astro CCD maker
• Pin's Astronomy Page

Have fun, RJS

I can sympathize with what you are trying to do, as I've tried both uses with my Nikon Coolpix 950. The short answer is both are possible, but it isn't likely to be easy to get what you want out of the setup. Once drivers are available, you should be able to use your digital camera as a webcam fairly effectively, though you may have issues with autofocus, flash, and other camera-only adjustments. For astrophotography, it isn't likely you'll be able to get worthwhile images with the Elph, but I've included a few links on how to get started.

Digial Camera Webcams

Digital cameras defintely produce a much more compelling image than a typical webcam. I have a 3Com HomeConnect (a pretty good quality webcam) and it looks just awful compared to my Nikon N950 (not just resolution, but also trueness of color, CCD noise, and sensitivity). The main limitations are that you can't usually take mini-movies or fast sequences, some key functions are often only controllable on camera (for instance auto-focus and flash), and you'll need a power cord for the camera if you don't want to drain the batteries very quickly.

The easiest way to control the camera from a linux box is with Scott Fritzinger's GPL'd gphoto program. gphoto allows basic control of a variety of cameras through serial or USB connection (and supports both interactive and commmand line modes - add a bit of perl and cron and you can do all sorts of fun things). Its still under development, however, and unfortunately doesn't currently support the Digital Elph (PowerShot S100) to my knowledge. I'm not sure how involved it would be to write a USB Elph driver for it, but you can check out the site if you feel up to it.

Digital Cameras and CCD Astrophotography

With astrophotography, you are getting into a rather specialized and involved use of CCD devices and generally speaking, it takes a good bit of expertise and dollars to get good results. You don't mention what you are looking to capture or what existing equipment you have, so I'll point out some of the basics and you can research further from these. FWIW, I'm not by any means an expert here, but I've been looking to jump in, so I'm seeing the same issues.

While there are limited exceptions, CCD astrophotography generally requires the use of specialized equipment. Your Canon Digital Elph doesn't have the required sensitivity (its equivalent to ISO 100 film), ability to take long exposures, long and fast enough lenses, or adapters for telescope mounting. While its possible to use a barn door tracker or equitorial tracking camera mount with the Elph, the results aren't likely to be worth the effort.

If you really get interested in astrophotography, you'll probably want to pony up for a specialized system like those built by Celestron and SBIG. These are highly sensitive, small array CCD cameras with specialized cooling and software for high gain operation. Add a high quality telescope, equitorial tracking mount, and related accessories, and you are talking about no small dollar commitment. Also, you'll need a lot of time and patience to find and capture accurately really good photos. I'd like to try CCD astrophotography out, but will be playing with 35mm (add a T mount and a Meade ETX and you can get started for under $1000) until I decide I'm really committed and move to a less light polluted neighborhood.

Sky & Telescope has a pretty good guide on where to start. Some good introductions to astrophotgraphy are:

• Sky and Telescope Imaging Resources
• Amateur Astrophotography links
• CCD Astrophotgraphy (annoying sounds)
• Santa Barbara Imaging Group (SBIG), a leading astro CCD maker
• Pin's Astronomy Page

Have fun, RJS

I can sympathize with what you are trying to do, as I've tried both uses with my Nikon Coolpix 950. The short answer is both are possible, but it isn't likely to be easy to get what you want out of the setup. Once drivers are available, you should be able to use your digital camera as a webcam fairly effectively, though you may have issues with autofocus, flash, and other camera-only adjustments. For astrophotography, it isn't likely you'll be able to get worthwhile images with the Elph, but I've included a few links on how to get started.

Digial Camera Webcams

Digital cameras defintely produce a much more compelling image than a typical webcam. I have a 3Com HomeConnect (a pretty good quality webcam) and it looks just awful compared to my Nikon N950 (not just resolution, but also trueness of color, CCD noise, and sensitivity). The main limitations are that you can't usually take mini-movies or fast sequences, some key functions are often only controllable on camera (for instance auto-focus and flash), and you'll need a power cord for the camera if you don't want to drain the batteries very quickly.

The easiest way to control the camera from a linux box is with Scott Fritzinger's GPL'd gphoto program. gphoto allows basic control of a variety of cameras through serial or USB connection (and supports both interactive and commmand line modes - add a bit of perl and cron and you can do all sorts of fun things). Its still under development, however, and unfortunately doesn't currently support the Digital Elph (PowerShot S100) to my knowledge. I'm not sure how involved it would be to write a USB Elph driver for it, but you can check out the site if you feel up to it.

Digital Cameras and CCD Astrophotography

With astrophotography, you are getting into a rather specialized and involved use of CCD devices and generally speaking, it takes a good bit of expertise and dollars to get good results. You don't mention what you are looking to capture or what existing equipment you have, so I'll point out some of the basics and you can research further from these. FWIW, I'm not by any means an expert here, but I've been looking to jump in, so I'm seeing the same issues.

While there are limited exceptions, CCD astrophotography generally requires the use of specialized equipment. Your Canon Digital Elph doesn't have the required sensitivity (its equivalent to ISO 100 film), ability to take long exposures, long and fast enough lenses, or adapters for telescope mounting. While its possible to use a barn door tracker or equitorial tracking camera mount with the Elph, the results aren't likely to be worth the effort.

If you really get interested in astrophotography, you'll probably want to pony up for a specialized system like those built by Celestron and SBIG. These are highly sensitive, small array CCD cameras with specialized cooling and software for high gain operation. Add a high quality telescope, equitorial tracking mount, and related accessories, and you are talking about no small dollar commitment. Also, you'll need a lot of time and patience to find and capture accurately really good photos. I'd like to try CCD astrophotography out, but will be playing with 35mm (add a T mount and a Meade ETX and you can get started for under $1000) until I decide I'm really committed and move to a less light polluted neighborhood.

Sky & Telescope has a pretty good guide on where to start. Some good introductions to astrophotgraphy are:

• Sky and Telescope Imaging Resources
• Amateur Astrophotography links
• CCD Astrophotgraphy (annoying sounds)
• Santa Barbara Imaging Group (SBIG), a leading astro CCD maker
• Pin's Astronomy Page

Have fun, RJS

1. Naked-eye observing (more rewarding than many people realize - especially those who haven't experienced country skies - if you can get to a nice, open area that's as far away from light pollution as possible). Check out the Internation Dark Sky Association for more information about "light pollution".
   
   
2. Buy a good pair of binoculars. Head to your library and quickly glance at the covers of the last two or three years of two magazines: "Astronomy" and "Sky and Telescope". It's guaranteed you'll see a review mentioned on the cover for binoculars that are especially well-suited for astronomy. Both magazines have typically done reviews of binoculars every few years.
   
   
3. If you've got the money to take a bit more of a risk (in case your daughter's interest fades in a year or two), then yes, consider buying a telescope. But as others have mentioned, stay away from "department store" telescopes (e.g. "Tasco" brand, etc.). A frequent indicator of an inferior telescope is one that tries to dazzle you with how much it magnifies things. It's often hard for beginners to understand, but this point is crucial for first time telescope buyers: magnification is not what you should be concerned about when buying a telescope! Any scope can be made to magnify any amount, just by changing the eyepiece. The critical things include the scope's ability to gather light (generally, the bigger the aperture the better), the tripod (don't consider this to be minor!), optical quality, overall construction, and so on.
   

1. Naked-eye observing (more rewarding than many people realize - especially those who haven't experienced country skies - if you can get to a nice, open area that's as far away from light pollution as possible). Check out the Internation Dark Sky Association for more information about "light pollution".
   
   
2. Buy a good pair of binoculars. Head to your library and quickly glance at the covers of the last two or three years of two magazines: "Astronomy" and "Sky and Telescope". It's guaranteed you'll see a review mentioned on the cover for binoculars that are especially well-suited for astronomy. Both magazines have typically done reviews of binoculars every few years.
   
   
3. If you've got the money to take a bit more of a risk (in case your daughter's interest fades in a year or two), then yes, consider buying a telescope. But as others have mentioned, stay away from "department store" telescopes (e.g. "Tasco" brand, etc.). A frequent indicator of an inferior telescope is one that tries to dazzle you with how much it magnifies things. It's often hard for beginners to understand, but this point is crucial for first time telescope buyers: magnification is not what you should be concerned about when buying a telescope! Any scope can be made to magnify any amount, just by changing the eyepiece. The critical things include the scope's ability to gather light (generally, the bigger the aperture the better), the tripod (don't consider this to be minor!), optical quality, overall construction, and so on.