If all the water currently trapped in all the glaciers across the entire world melted, the sea level would rise far more than most people imagine. Almost everyone living anywhere in the world at an elevation of below about 500 feet with a direct drainage to the sea would be directly affected; The sea level rise itself might be a bit over 300 feet, but oceans tend to migrate horizontally when they rise onto previously uninnundated land surfaces. So if you lived at 500 feet above sea level in most of Maine, you'd have a much shorter walk to the rocky shoreline, but if you lived at 500 feet across much of the Gulf Coast it would only be a matter of time until the eroding sea cliff reached you incorporated you into the offshore sediments.
Having said that, Anthropogenic Global Warming has resulted in only modest sea level rise to date, and it is at this point probably true that warming of the ocean causing thermal expansion has been at the same level of magnitude (or greater) than seas rising because of the influx of melted glacial water.
The problem is, it is very difficult to measure either sea level rise or ice loss very accurately, for a number of reasons. But there is a saving grace. Or should I say, GRACE. GRACE is a NASA project; Twin satellites measure changes in the Earth's gravity field in such a way that it is possible to identify changes in the distribution of water. From the GRACE overview statement:
Through a weird quirk of scheduling, I haven't actually taught the intro modern physics course since I started writing pop-science books about modern physics. So, this week has been the first chance I've really had to use material I generated for the books to introduce topics in class.
In the approximately chronological ordering of the course, we're now up to the late 1800's, and the next book we're talking about is Einstein's Clocks, Poincar$eacute;'s Maps, which talks about how Einstein and Henri Poincaré were (arguably) influenced by developments in timekeeping as they looked for the theory that became Special Relativity.
This is a much more academic book than the previous readings, and as such has really long chapters and sections. To space things out a little bit (giving them more time to read), and to give them a better idea of what relativity is about (which I think is helpful when reading Galison's discussion), I've spent the last two classes talking about relativity. Monday's lecture introduced Special Relativity and spacetime, and today's lecture introduced the Equivalence Principle and general relativity. Those slides are a little short on words because I was largely copying figures from the book, and because I'm trying to generate less wordy PowerPoints as a general matter. They should give you the right basic idea, though, and if you want more explanation, well, you can pre-order How to Teach Relativity to Your Dog (or enter our Photoshop contest)...Read the rest of this post... | Read the comments on this post...
Actually, they can't, but they're having fun.Read the comments on this post...
I have a Google alert set up to let me know whenever my name or the title of one of my books turns up in one of the sources they index. This is highly imperfect, sometimes missing interesting articles, and often blorting out 57 different pages on which my name appears in a sidebar link. It comes in handy from time to time, though, such as this morning, when it coughed up a whole bunch of pages linking to the Polish edition of How to Teach Physics to Your Dog:
Finally, dogs in the ancestral homeland of my father's family can learn all about quantum physics. I'm a little surprised to learn that the default dog in Poland is a miniature schnauzer ("Frickin' schnauzers..." Emmy grumbles), but it's always nice to see a new edition. I believe we've already sold Polish rights to How to Teach Relativity to Your Dog as well, so there's that to look forward to.
I don't have physical copies of this yet, but I'll presumably get at least one at some point. Which means I'll be all set for Christmas gifts for my aunts and uncles that year...Read the comments on this post...
A quick reminder: How to Teach Relativity to Your Dog (cover in the left sidebar) will be released at the end of the month. If you'd like to win a signed copy early, though, you can enter our Photoshop contest. Just edit a picture of Emmy into another picture having something to do with physics. Like this:
(See the transcript here for the source of this comment.)
The deadline for entering is this Friday. We've already got some quality entries, but the more the merrier.Read the comments on this post...
Proving that you can find physics in everything, Sean Carroll points to a strange anomaly in the Super Bowl coin toss: the NFC has won 14 coin tosses in a row. The odds of this happening seem to be vanishingly small, making this a 3.8-sigma effect, almost enough to claim the detection of a new particle, and certainly enough to justify the generation of a press release.
Of course, there are two problems with Sean's analysis, one classical and one quantum. The classical objection is that what we have a record of is one team winning the toss every time, which does not mean that the coin is doing anything wonky. There's probably somebody out there who has a record of whether the coin came up heads or tails in each of those tosses, but that's not the same thing. To calculate the probabilities correctly, you'd need to know something about the distributions of "heads" vs. "tails" calls by super Bowl team captains, which may or may not be 50-50.
More importantly, though, the quantum objection renders this moot: If you believe in a Many-Worlds or multiverse interpretation of quantum physics, the probability of the NFC winning fourteen consecutive coin flips is 100%-- among the effectively infinite branches of the wavefunction of the universe, there must be one in which the 14-in-a-row streak has occurred. And also one where the AFC has won all 45 Super Bowl coin tosses, and one in which the coin has landed on edge 45 times in a row, and so on.
This might seem like a bucket of cold water thrown on an otherwise fun bit of geeking out, but it's actually a cause for hope. After all, if there are all these improbable universes out there with weird things happening in the coin toss, there must also be universes in which weird things happened in the game. But then, we know that already, from Super Bowl history-- two of my Giants' Super Bowl titles came about in a fashion that clearly indicates some quantum fluctuations in action (the third was a thorough drubbing of the Broncos). At least from where I sit, this puts us in the best of all possible football universes. But for those of you who root for other teams, take heart-- somewhere out there in the multiverse, there's a universe in which the 2007 Patriots went 19-0, and even one in which the Buffalo Bills had an unprecedented run of four consecutive titles in the 90's.
Well, OK, maybe that's a little too unlikely, even for quantum physics...Read the comments on this post...
"More days to come / New places to go
I've got to leave / It's time for a show
Here I am / Rock you like a hurricane!" -The Scorpions It isn't just Earth, of course, where these great cyclonic storms occur, whipping across the planet and wreaking havoc as they rage above the surface. Most famous, perhaps, is Jupiter, whose great red spot has existed for as long as we've been able to see at the necessary resolution.
But one doesn't often think of Saturn when it comes to devastating storms.
(Image credit: Earth-based telescope, retrieved from SolarSystemQuick.com.)
Saturn, quite famously, is a great gas giant planet, second only in size to Jupiter in our Solar System, and renowned for its spectacular rings. And although Saturn's rings are its most obvious feature, the clearly defined, featureless bands along its different latitudes also stand out.
Unless, that is, you've taken a close look in the last year or so.
(Image credit: Trevor Barry, Broken Hill, Australia.)
That is not a featureless band up there in Saturn's Northern Hemisphere!
Quite to the contrary, this is a virtually planet-wide storm plume, whose core is a 3,000-mile-wide thunderstorm, kicking up beacons of warm air and leaving behind ammonia ice crystals, which we can tell from Cassini's observations in the infrared.
(Image credit: NASA / JPL / Univ. of Arizona.)
Cassini, the famed Saturn spacecraft that's been orbiting our ringed neighbor for nearly a decade, first spotted this storm in the earliest stages of its infancy, all the way back in early December, 2010. I've highlighted it, below, visible right at Saturn's terminator.
(Image credit: NASA / JPL-Caltech / Space Science Institute.)
Unlike storms on Earth, which typically last for days or -- in particularly devastating cases -- a few weeks, this storm on Saturn has set a new record.
Lasting for more than 200 days, this Saturnian tempest rages all the way into August of last year, with the storm's head lasting intact at least into May. This made it the longest-lasting storm of this kind ever seen on Saturn; the first one since 1990 and the longest one since the first one was ever observed, all the way back in 1876!
As you can see, it was so powerful that, from February to April, the storm actually lapped itself, with the head of the storm clearly visible in those images.
What you might not realize is that Cassini was also able to clearly identify the tail of the storm, by looking in the infrared! Below, in false-color, the red-orange methane clouds are topped by a high blue haze signifying the main end of the tail. (The rings also appear in blue as a thin line, as there is no methane there at all!)
(Image credit: NASA / JPL-Caltech / Space Science Institute.)
Although this is all that NASA released, Cassini is a bit of a special mission. You see, they have a publicly accessible imaging diary over at Cassini Imaging Central Laboratory for OPerationS (CICLOPS).
Want to see how the storm changed from one (Saturnian) day to the next? Taken 11 hours apart, from February 23rd, 2011 to February 24th, you can really see that -- at a scale of 64 miles (104 km) per pixel in the below image -- this giant hurricane is migrating across the face of Saturn at around 100 km/hr!
(Image credit: NASA / JPL-Caltech / Space Science Institute.)
And finally, what can Cassini do, at its highest resolution in (nearly) true color, looking at the storm as it traverses its own wake across the planet? Click on the image for full-resolution, but even at its reduced screen resolution... well, see for yourself!
(Image credit: NASA / JPL-Caltech / Space Science Institute.)
You can follow the entire saga of the Saturn Storm Chronicles' report on last year's record-breaking display over at CICLOPS, but what an amazing view from Cassini!Read the comments on this post...
It's been a little while since I wrote up what I've been doing in my "Brief History of Timekeeping" class, because I was out of town, and then catching up from being out of town. Some of this material has already appeared here, though, so I can hopefully catch up a lot of stuff in one post.
The material that will be most interesting to random readers of the blog is the "How to" section, from a couple of weeks ago, which were the lecture form of the How to Read a Scientific Paper and How to Present Scientific Data posts here. The paper-reading class was on Monday and the data-presentation class on Friday, with a class going through a particular paper on The mechanics of the sandglass sandwiched in between. This also served as the explanation of the working of sand timers, one of our historical timekeeping technologies.
The next week was shortened because I was out of town for the weekend, and introduced mechanical clocks. I started off with this video clip from Connections, which provides a very nice illustration of early mechanical clocks:
Also, you could land an airplane on the lapels of that jacket. As I told the students, I'm just barely old enough to remember the brief moment when that didn't look ridiculous.<.p> Read the rest of this post... | Read the comments on this post...
Popular Science, one of the leading sources of news in technology, science, gadgets, space, green tech and more, is returning as a key Media Partner with the Festival!
In doing so, PopSci joins a growing list of other top science media leaders who will be serving as Festival sponsors, including Popular Mechanics, Scientific American, MIT's Technology Review, Chemical & Engineering News, School Tube.com, ENGINEERING.com, EE Times and PBS Kids.
PopSci has been a major source of science and technology news since its award-winning magazine Popular Science was founded back in 1872. Its online version, PopSci.com, was launched in 1999, and in 2008 this site was redesigned and upgraded to give viewers even more up-to-the-minute tech news and insightful commentary on new innovations, and even scientific angles on the hottest Hollywood movies and stories.
Returning from its stint as a valued Media Partner in the 2010 Festival, Popular Science, like other key media sponsors in next year's event, will run advertisements pro bono via their respective media outlets which will play a key role in not only giving the Festival heightened visibility on a national and international scale, but also will help the event recruit for new satellite venues and participation in the Expo, contests and other activities.
Published by the Bonnier Magazine Group (which also publishes Science Illustrated), Popular Science is long known for its commitment to journalistic excellence in reporting on the latest in innovation, while giving readers an insightful look into what the future of technology holds.
Says Gregg Hano, Senior Vice President of Bonnier Corporate Sales & Technology Group, "We invest in that vision with our media properties everyday, and supporting the USA Science & Engineering Festival is one more way for us to ensure that the next generation will have the skills, knowledge and interest to deliver on that bright future."
We thank Popular Science and our other Media Partners for their valued participation!
It's now officially February, and the release date for How to Teach Relativity to Your Dog is only a few weeks off-- the official release date is Feb. 28. Of course, I've got a copy already:
If you would like a copy of your very own, you can either wait until the release, or take part in this shameless publicity stunt: The second-ever Dog Physics Photo Contest!
Last time around, we did a LOLEmmy contest for a bound galley proof of the first book. This time, I'm giving away a signed copy of the finished book, so we'll go for something a little trickier: I've picked three pictures from my Flickr set of dog photos, showing Emmy sitting, play-bowing, and moping. Your challenge, should you choose to accept it, is to crop her out of one of those three, and edit her into some other scene. Like this:
The best photoshopped picture of Emmy wins a signed copy of How to Teach Relativity to Your Dog. Rules and conditions below the fold:Read the rest of this post... | Read the comments on this post...
Thursday Eratosthenes Blogging: Measuring Latitude and Longitude with a Sundial [Uncertain Principles]
As I keep saying in various posts, I'm teaching a class on timekeeping this term, which has included discussion of really primitive timekeeping devices like sundials, as well as a discussion of the importance of timekeeping for navigation. To give students an idea of how this works, I arranged an experimental demonstration, coordinated with Rhett at Dot Physics. We've been trying to do this literally for months, but the weather wouldn't cooperate. Until this past weekend, when we finally managed to make measurements that allow us to do some cutting-edge science. For 200 BC, anyway...
So, what did we do? Well, we each made a sundial, and shot time-lapse video of it using a webcam. Here's mine-- note the Lego gnomon, graciously donated to science by SteelyKid (whose attempts to help with "Daddy's 'spermint" weren't enough to earn a co-author credit, but do rate this acknowledgement):
The too-bright first few frames are because I forgot to adjust the exposure initially, and the greying out at the end is because some thick clouds rolled in. This was shot in our back yard in Niskayuna, and simultaneously (in some frame of reference, anyway), Rhett was taking video of his own sundial, in Hammond, LA. I took both videos, and ran them through Tracker video to measure the position of the end of the shadow for each frame, and produced the following results:Read the rest of this post... | Read the comments on this post...
"The Earth's atmosphere is an imperfect window on the universe... atmospheric turbulence blurs the images of celestial objects, even when they are viewed through the most powerful ground-based telescopes." -John Bahcall There's no doubt that the Hubble Space Telescope has given us some of the most spectacular, high resolution views of the Universe. From the most distant galaxies ever seen to stars here in our own galactic backyard, the Hubble Space Telescope has simply dwarfed anything we've been able to do from Earth's surface.
(Image credit: Bill Drelling.)
This is the globular cluster NGC 288, separated by just over 1 degree from the famed Sculptor Galaxy, as seen through a simple 3" telescope. Larger telescopes can, of course, do better, but from high above the Earth's atmosphere, Hubble's 2.4 meter primary mirror has given us this view of this remarkable object.
(Image credit: ESA/Hubble & NASA.)
Absolutely amazing! For over 20 years, Hubble has been returning images like this, with a resolution of just a couple of hundred-thousandths of a degree!
The reason it can do this, of course, isn't its size. At 2.4 meters, Hubble is pretty large, but we have plenty of 8-meter and 10-meter telescopes here on Earth, which could get much better resolution than Hubble if they were in space. No, Hubble's advantage is its location.
(Image credit: NASA, retrieved from the Urban Astronomer.)
While ground-based telescopes have the entire atmosphere to contend with, complete with turbulent air, a slew of different, moving layers, and intervening molecules, Hubble is literally above all that. Despite their extra size, ground based telescopes haven't been able to compete because of the atmosphere.
But a new technology -- adaptive optics -- is changing all of that. Here's how it works.
(Image credit: Gemini Observatories, NSF / AURA, CONICYT.)
You start by shooting a powerful laser with very well-defined frequencies, like this sodium laser, creating a guide star that's in the direction you're taking your observational data. You're seeing light from all of the actual stars, galaxies, etc. -- you know, the real observing targets -- as well as your artificial guide star. The beauty of using a sodium laser is that, around 100 km up, there's a thin layer of sodium in Earth's atmosphere that will absorb and re-emit the light back towards your telescope.
All the light that comes in, both from your real targets and from your guide star, gets distorted by the atmosphere. But, since you know what your guide star is supposed to look like, you can take the blurred, incoming signal from the guide star, and compute what type of weird, fun house-style mirror you'd need to un-blur the image!
(Image credit: retrieved from Isa Garcia's blog.)
Just like a fun house mirror distorts normal images, the right fun house mirror can fix distorted images, if you create just the right mirror. But if you can create the proper mirror to fix the guide star (i.e., the light from the laser), you can also fix the light from your observing targets! Creating a system that continuously adapts its mirror to the changing atmosphere, giving you an undistorted image of your observing target at the end, is the end-all goal of adaptive optics.
(Video credit: 3 minute visualization of an AO system, by Gemini Observatory.)
And when this is put into practice, adaptive optics is capable of taking what looks like turbulent, nonsense noise and turning it into a crystal-clear, real-time image of what actually lies out there in the Universe.
Want to see it in action? Take a look at this 2006 video of adaptive optics taking on a binary star system; you seriously won't believe it.
(Movie Credit: Guido Brusa, CAAO, Steward Observatory.)
That was then.
Just a couple of months ago, Gemini South Observatory released their first light image from GeMS/GSAOI, the world's most advanced adaptive optics system, attached to the 8-meter Gemini Telescope. And wouldn't you know which object they happened to take a look at for their very first image?
(Image credit: Gemini Observatory / NSF / AURA / CONICYT / GeMS/GSAOI.)
Wouldn't you know: it's globular cluster NGC 288! As the GeMS Principal Investigator, François Rigaut was absolutely amazed at this image, and said,
We couldn't believe our eyes! The image of NGC 288 revealed thousands of pinpoint stars. Its resolution is Hubble-quality - and from the ground this is phenomenal. This is somewhat uncharted territory: no one has ever made images so large with such a high angular resolution.
Although all of that is true, I think University of Toronto Astronomer Roberto Abraham more encapsulated my reaction to this image, when he said,
This is fan-freaking-tastic!!!!!!! And it is! If you horizontally flip and (slightly) rotate the raw image, you can actually overlay it atop the Hubble image back at the top of the page, and compare these two directly!
At this zoomed-out resolution, it doesn't look all that impressive, especially considering the monochrome nature of the ground-based image.
But let's take a look at a very small region -- those four bright horizontal stars towards the center of the above image -- with both the Hubble Space Telescope and the Gemini telescope with the new adaptive optics!
Even at first light -- with its very first image -- the GeMS/GSAOI adaptive optics were easily just as good as Hubble's resolution, the first time that a ground-based telescope has ever done that!
Of course, that was like, two months ago already, so Gemini has since gone on to take even higher resolution images than Hubble can, like this one of NGC 2362.
(Image credit: Gemini Observatory / GeMS/GSAOI.)
Sorry that there's no Hubble image of this to compare with, only a Spitzer image that really looks like a joke, particularly next to the full-resolution Gemini version. When you're looking at the image above, remember that each quadrant is less than one ten-thousandth of a square degree! Highest. Resolution. Image. Ever.
And that's how you defeat Hubble without ever leaving the ground!Read the comments on this post...
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The University of Puerto Rico at Arecibo has a very interesting facility that has put out some fun stuff
And I suspect he's done so willingly. Well, you know what they say about statistics and liars.
Here's the story. The Wall Street Journal and the Daily Mail independently published highly misleading and blatantly idiotic pieces on climate change. We've covered this extensively already over the last few days. Phil Plait, of the Bad Astronomy Blog on Discovermagazine.com, was one of numerous scientists to respond to those flaming examples of horrific bottom feeding journalism with the post "While temperatures rise, denialists reach lower." In that post, he presented a still-image from a moving GIF that has been going around, originally from Skeptical Science. I've used the GIF myself just recently, but I'll re-post it here for your convenience:Read the rest of this post... | Read the comments on this post...
Come the Festival to Hear Featured Author Theodore Gray! [USA Science and Engineering Festival: The Blog]
"The periodic table is the universal catalog of everything you can drop on your foot"
You have the amazing opportunity to hear from best-selling author Theodore Gray at this year's USA Science and Engineering Festival Book Fair! Gray will be speaking at the Teen Non-Fiction Festival Stage at 11:50 am on Saturday, April 28th. His newest book is Theodore Gray's Elements Vault: Treasures of the Periodic Table with Removable Archival Documents and Real Element Samples - Including Pure Gold! Gray's other books, The Elements and Mad Science, are international bestsellers, as is the wildly popular The Elements for iPadebook.
Theodore Gray's Elements Vault picks up where The Elements left off. Organized into the nine major groups of the periodic table, including the alkali metals, the alkali earth metals, the transition metals, the nonmetals, the metalloids, the halogens, the noble gases, the actinides, and the lanthanides, Elements Vault includes all new text, new photographs, and even more information about the elements.
Elements Vault also includes 20 removable historic documents related to the elements and the field of chemistry, such as Einstein's famous letter to Roosevelt explaining the potential of uranium for use in nuclear weapons, a genuine advertisement for lithium-laced 7UP soda, Mendeleev's original notes on the periodic table, and more. Each of these documents is individually packaged in an envelope attached to the book page. The document can be removed and handled and then put back into the book for safekeeping. Also included is a gorgeous 20″ x 10″ poster of the unique rainbow spectrum emitted by each element in the periodic table.
Along with all the information and fascinating facts about the elements, readers will discover the irresistible dry wit and humor of chemist and Popular Science contributor Theodore Gray. Cecil Adams, of "The Straight Dope" says, "Gray...has attained a level of near superhuman geekery that the rest of us can only mutely admire."
"Even if this book weren't absolutely gorgeous, it would still be a worthwhile investment because of how well it works as Coffee Table Education. This is when you leave a book lying around that is so tempting the kids pick it up and start learning stuff without even being asked! Delightful."
I'm using Dava Sobel's Longitude this week in my timekeeping class. The villain of the piece, as it were, is the Reverend Dr. Nevil Maskelyne, who promoted an astronomical method for finding longitude, and played a major role in delaying the payment to John Harrison for his marine chronometers. It's a good story, with lots of science and engineering and politicking.
There's one critical flaw, though, in terms of me teaching this book, which is that I don't really know how to say Maskelyne's name. And even Wikipedia is letting me down, here, by not providing a phonetic rendering of his name. Which means I'm depending on you, my wise and worldly readers, to help me figure this out:
Nobody had even begun to think about quantum physics during Maskelyne's lifetime, so you're only allowed to pick one answer, not a quantum superposition of multiple answers.Read the comments on this post...
Michael Mann, famous climate scientist, has released a book called The Hockey Stick and the Climate Wars: Dispatches from the Front Lines (also available as a Kindle edition). I've not read it yet but I thought you'd like to know about it.
Michael Mann is the guy who came up with the Hockey Stick graph and metaphor. Early reviews are positive:In this meticulous and engaging brief on climate change research and the political backlash to legitimate scientific work, Penn State professor Mann narrates the fight against misinformation from the inside. (Publishers Weekly )
An important and disturbing account of the fossil-fuel industry's well-funded public-relations campaign to sow doubt about the validity of the science of climate change.
Kirkus (STARRED REVIEW)
If you don't believe our climate is changing, read this book. Dr. Mann will change your mind. For us, it's a war of words. Preserve the Earth, and pass the ammunition. (Bill Nye the Science Guy )Read the comments on this post...