Disturbing Amount of Arctic Ice Melted This Year

The Arctic ice cap melted by an unprecedented amount this year. Especially prominent in media stories was the opening up of the fabled “Northwest Passage”. While there have been many articles covering this (the attention is good!), La Marguerite drew my attention to a very nice piece in the New York Times, entitled “Arctic Melt Unnerves the Experts”. I especially liked their interactive graphic illustrating the extent of sea-ice loss.

This does not bode well for the upcoming years.

Global Warming Forces Cartographers to Redraw Maps

Inel’s blog drew my attention to the publication of the newest edition of the prestigious Times Comprehensive Atlas of the World. We tend to think of updated atlases showing new political boundaries, or new supplementary statistics. But thanks to global climate change, coastlines are changing and ice caps melting. The Times Atlas‘s cartographers had to make far more changes than usual for this last edition, and future editions will clearly have even more changes with which to contend.

The importance of this extends beyond work for cartographers and lines on a map. People live in those areas. They obtain fresh water from those areas. Those areas power their weather. And as Americans are belatedly catching on, that which occurs in one country doesn’t stay confined to that country. The effects ripple out across the globe.

For more information about this, please see Inel’s blog or a New Scientist article.

Modern Fish, Coelacanths, Tiktaalik, and Us

Tiktaalik roseae, illustration
An illustration of Tiktaalik roseae from Wikipedia. Credit: ArthurWeasley.

In the last several years, scientists have mapped in detail the lines of descent that resulted in aquatic vertebrates (fish) being able to survive and function outside water—including lines of descent that today have resulted in the mammals. Periodic discoveries stimulate interest in the media, such as the discovery last year of the 375-million-year-old Tiktaalik, or occasional sightings of coelacanths, an order of fish once thought to be long-extinct. But how are these animals related to each other and to us?

New Scientist published an article last week discussing new research into the coelacanth’s fins (specifically, when the difference between the coelacanth’s symmetric appendages and our asymetric appendages arose). But what I found especially interesting was a graphic demonstrating the relationships between extant lifeforms and notable extinct relatives, including when they are thought to have lived.

Diagram showing relationship between extant fish and tetrapods and extinct relatives.
See full-sized image. Source: New Scientist.

Perhaps this will help provide a framework when reading about these fascinating animals.

Google Earth Adds…the Universe!

I already thought the free Google Earth program was one of the coolest programs out there. Sort of a “digital globe”, you can zoom from looking at the entire Earth right up to your house or favorite location, change viewing angles, and fly to other places. That alone can occupy me to no end, but there is so much more you can do with the program. I think a good side benefit of Google Earth—and I’ve remarked on this before—is that to some degree, I feel it helps promote interest in geography. As one goes about exploring places, it’s difficult not to appreciate their geographical relationships, and eventually one starts exploring other parts of the world, as well.

But now Google’s taken this a step further. In their newest version, they’ve added the ability to explore the sky as well. Complete with Hubble imagery and loads of astronomical tidbits, this is a great new feature and one I hope will stimulate interest in astronomy.

Below is a video demonstration Google has created. There has also been a significant amount of media coverage—see, for instance, articles in New Scientist, SPACE.com, PC World, or other media.

I should note that the astronomical view is displayed as one might see it from Earth—sort of on the inside of a dome, not unlike a planetarium view. You cannot travel out into space. For that, I strongly recommend the excellent, free, and easy-to-use Celestia (wp). It’s beautiful, has an elegant interface, and is quite powerful. Google Earth plays a rather different role, and both programs complement each other nicely. I strongly urge everyone to download and explore both!

Update: Scientific American has a nice article, as well.

Map of Online Communities

XKCD, a webcomic, recently featured this map of online communities.


Map of online communities
See full-size image. XKCD webcomic. Used with permission.

This “map” is deceptively simple, but a surprising amount of information is packed into it, and this ability to convey such information in such an easily grasped format is what makes it so effective. I’d like to think this weblog is somewhere near the eastern edge of the “Blogipeligo.”

Hinode Reveals Sun’s Surface Activity

NASA just released some great images and video clips taken by Hinode, a Japanese space telescope studying the sun. As described by New Scientist,

The restless bubbling and frothing of the Sun’s chaotic surface is astonishing astronomers who have been treated to detailed new images from a Japanese space telescope called Hinode.

The observatory will have as dramatic an impact on our understanding of the Sun as the Hubble Space Telescope has had on our view of the universe beyond, scientists told a NASA press conference in Washington, DC, US, on Wednesday.

(continue reading at New Scientist)

Sun's surface
Image credit: Hinode JAXA/NASA

They’ve released several images, including the one I’ve featured here (see the high-resolution version). The caption states

Taken by Hinode’s Solar Optical Telescope on Nov. 11, 2006, this image reveals the fine scale structure in the chromosphere that extends outward above the top of the convection cells, or granulation, of the photosphere. The structure results from the interaction of hot ionized gas with the magnetic field.

The video clip below really shows off the sun’s surface activity. You can see a higher-resolution version at NASA’s web site, along with other video clips from Hinode.

This incredible activity is taking place along the entire surface of the sun, all the time. It’s amazing: the sun appears unchanging and placid from Earth, yet its surface (and interior) are alive with activity.

Hinode (formerly known as SOLAR-B), is a satellite with three instruments: the Solar Optical Telescope, X-ray Telescope, and Extreme Ultraviolet Imaging Spectrometer. Its purpose is to study the sun. It is primarily run by JAXA, the Japanese Aerospace Exploration Agency, in collaboration with the space agencies of the United States, the United Kingdom, and the European Union. Read more at NASA’s page.

Crossing Saturn’s Rings

The Cassini imaging team (CICLOPS, the Cassini Imaging Central Laboratory for Operations) just released some new images of Saturn today. Among them is this incredible time-lapse video from photographs Cassini took as it crossed Saturn’s ring plane. You can see how thin the rings are as the orbiter crosses them.

The spacecraft crosses the ring plane twice each orbit. This video represents approximately twelve hours and so runs around a thousand times faster than real time. Cassini starts on the sunlit side of the rings, then crosses to the darker side. We see six moons during the video, though the smaller ones aren’t really visible at the low-resolution version of the video I’ve shown here. A high-resolution version is available at the CICLOPS web site and is definitely worth the download. The first large moon is Enceladus; the second one is Mimas.

The Cassini spacecraft was launched from Earth on 15 October 1997 as part of the Cassini-Huygens mission, a joint project between NASA, the ESA (European Space Agency), and the Italian Space Agency. It entered into Saturn orbit on 1 July 2004. It is the first spacecraft to orbit Saturn and the fourth one to visit it (after Pioneer 11, Voyager 1, and Voyager 2).

(Thanks to the Bad Astronomer for the link!)

Equations on WordPress

WordPress.com just added support for using inline \textrm{\LaTeX{}} [Wikipedia], a freely available protocol for using typesetting and displaying mathematics and other technical information. It is powerful and not too difficult to learn the basics. Equations can now be placed within a paragraph, such as Einstein’s famous and world-changing E=mc^2. Of course, one could use regular HTML to display such an equation (E=mc2), but where \textrm{\LaTeX{}} really shines is for more complex formulas. For instance, the volume of a sphere (using a cylindrical coordinate system) is V=\int_0^{2\pi} \int_0^R \int_{-\sqrt{R^2-r^2}}^{\sqrt{R^2-r^2}} r \, dz \, dr \, d\theta = \frac{4}{3}\pi R^3. This is a very useful feature and I’m quite impressed that WordPress.com has offered it.

Update: WordPress.com has been busy! \textrm{\LaTeX{}} has now been enabled in comments as well. Furthermore, by using the\displaystyle command, one can have the equation display separately on its own line, instead of the vertically compact inline style used above. For instance, the volume equation I previously discussed would be displayed as follows:

\displaystyle V=\int_0^{2\pi} \int_0^R \int_{-\sqrt{R^2-r^2}}^{\sqrt{R^2-r^2}} r \, dz \, dr \, d\theta = \frac{4}{3}\pi R^3

For those unfamiliar with \textrm{\LaTeX{}} , it is really quite easy to learn. For reference, the code I have used here is as follows:

  • $latex \textrm{\LaTeX{}} $
  • $latex E=mc^2 $
  • $latex V=\int_0^{2\pi} \int_0^R \int_{-\sqrt{R^2-r^2}}^{\sqrt{R^2-r^2}} r \, dz \, dr \, d\theta = \frac{4}{3}\pi R^3 $
  • $latex \displaystyle V=\int_0^{2\pi} \int_0^R \int_{-\sqrt{R^2-r^2}}^{\sqrt{R^2-r^2}} r \, dz \, dr \, d\theta = \frac{4}{3}\pi R^3 $

Finally, \textrm{\LaTeX{}} is pronounced with a hard k sound at the end; it comes from the Greek letter Χ (chi). See Wikipedia for more information.

Any questions?

DNA Animations

PZ Meyers posted a neat animation on his weblog “Pharyngula” the other day. The first part shows DNA coiling and packaging; the second part DNA replication.

They’re from a web site called DNA Interactive; you can see more excellent animations there.

I especially like these because they portray the complexity and beauty of these ubiquitous cellular processes, yet also exhibit their chemical, mechanical nature. We tend to personify biological phenomena (“the DNA unwinds, then adds complementary base pairs to each strand”); it’s easy to forget that these are essentially mechanical, step-by-step processes.

And yet they’re still beautiful.

Planet and Star Size Comparison

Via THS Earth/Space Science (a weblog for a 9th-grade science class), I came across this neat animation comparing the relative sizes of planets in our solar system and various stars. It really does a good job!

Humans evolved on Earth, and our brains do a poor job grasping sizes much larger (or much smaller) than that which we’d find in our typical environment. True, we can describe it mathematically, but it’s so difficult to really see the comparison.

Unfortunately, I do not know who the creator of this video is. No credits are given, and a web search was unsucessful. It is perhaps European, based on the spelling of the star names. If anyone has any information, please let me know.

Update: It appears the original video used copyrighted music without permission of the copyright holder, and has been removed. I changed the post to a different version of the video without music.

Update #2: The old link no longer worked (thanks, Sara!) so I updated it.