*I was going to create diagrams to go along with this post but I just don’t have time today. You’ll have to envision it in your mind’s eye. 

*For more on winter weather in general, check out my reeeeeally old post about winter weather in the south

I will go out on a limb and say that weather-wise, the past 5 days or so have been just about the ugliest, most depressing string of days Nashville and middle TN have seen in quite a while. This is all due to a rather interesting weather scenario across the whole nation. I will attempt to concisely explain the factors involved, and hopefully you’ll also see why these types of storms are so incredibly hard to forecast.

First of all, last weekend (Jan. 11th & 12th) were unseasonably warm and also very rainy, especially Saturday. This was due to a large upper level “cutoff” low pressure system that parked itself right over the southwestern U.S. Because this system was in the upper levels of the atmosphere (about 18,000-30,000 ft) where the main branches of the jet stream exist, it controlled on a broad scale which airmasses were influencing which parts of the nation. The big trough of low pressure stubbornly sat spinning over the western 1/2 of the U.S. for several days, causing the jet stream to dig southward over the west, then shoot northeastward over the midwest and on into the northeast. The southern branch of the jet stream was allowed to surge northward and pump lots of warm moist air from the Gulf and northern Mexico up across the southeast and even into the northeast U.S., bringing the soaking rain and warm temps we had over the weekend. Meanwhile, the northern branch of the jet stream was doing just the opposite, pumping dry frigid air from Canada down over the western and southwestern U.S.

Finally on Sunday Jan. 13th, the huge upper-level low pressure pushed eastward across the nation, and thus the cold arctic air across the west pushed eastward along with it, creating a very sharp cold front at the surface that moved across Nashville that afternoon. You may remember that the temp was a balmy 65F or so Sun. morning, and around 3:30pm it plummeted 15-20 degrees over the course of about 2 hours.

That was part 1 of this crazy chain of events. Now for part 2:

After that initial surge eastward, the upper-level low pressure trough stalled out yet again, leaving that sharp cold front draped roughly along the spine of the southern Appalachians. The cold airmass wedged down at the surface (we all remember from basic science that cold air sinks and warm air rises, right?) but after it stalled out, the southern jet stream was still active. Monday & Tuesday of this week we had a battle between the southern flow of warm Gulf moisture and the stubborn cold airmass that surged eastward Sunday. The warm moist air has been sliding up and over the heavy cold air at the surface and thus we’ve had sleet and freezing rain across the whole middle TN area as the two forces have been at a stalemate. Temps in the mid-levels of the atmosphere have been steadily 6-10 degrees warmer than at the surface. This is an old diagram I made showing a simplified version of how that looks as a cross-section:

icestorm

Judging exactly where that freezing line will be on the surface is nearly impossible. Thus, forecasts for this type of weather are rarely accurate on a local scale. Last night, the Nashville metro area got lucky in that the freezing line at the surface ended up being just to the west of us- the temp held at about 33 or 34 degrees. This large trough is finally going to push further eastward tomorrow, as yet another piece of Gulf moisture and energy combines with a surface-level low pressure system moving east out of Texas. That will bring the possibility of significant snow and ice to east TN, southern VA, and western NC. Nashville will be spared any precipitation from that system, though, and most of the southeast is forecast to remain firmly in the grips of that arctic airmass for at least another week or so, so keep your heavy coats handy.

Image via Universe Today

Image via Universe Today

You may have heard about the killer asteroid aptly named Apophis, which had a chance of hitting earth in 2036 and potentially devastating a good chunk of the human population. Thankfully, scientists have now made more accurate observations of Apophis and ruled out the possibility of it hitting earth.

The asteroid has been on a watch list for many years because in 2029 it will pass very VERY close to earth. So close that it will actually be inside the orbit of some of our satellites! The fear was that if the asteroid passed through a very specific spot as it passed us, the earth’s gravity would tug on it just right so that its orbit would be altered and it would hit earth on its next pass in 2036. Due to limited observations of Apophis, astronomers didn’t know its exact orbit accurately enough to determine if it would pass through this very specific gravitational “keyhole.” Even before this latest observation, which occurred during its latest flyby of earth, the odds of Apophis passing through that keyhole were very slim (about 1 in 100,000 if I remember correctly, but don’t quote me on that) but significant enough to worry. Further observations a few years ago lessened the odds considerably to about 1 in 1,000,000. Now, astronomers are absolutely positive the rock will not pass through that gravitational keyhole, and the rock will never hit earth. They also learned from these latest observations that Apophis is actually larger than originally thought- about 325 meters in diameter, vs. 270. So it’s a really good thing that this rock won’t hit us!

This does not mean we can sit back and relax, however. There are probably thousands of asteroids flying around out there that we haven’t even seen yet, and any of them could be on a collision course with us. It’s a very real threat, and based on our knowledge of past extinctions and impacts, statistically it’s only a matter of time before we get smacked by another one. We just have be able to detect it before it hits us, and have the technology in place to deflect it.

More detailed info can be found at Bad Astronomy and Universe Today.

This is an interesting short documentary episode from Vice’s Motherboard series on Copenhagen Suborbitals, a self-proclaimed “open-source, do-it-yourself space endeavor” started by two really smart guys in Denmark. Basically they want the world to realize that getting to space is actually a very achievable thing for average people if they really truly want to do it. It’s an awesome idea and one that I applaud whole-heartedly. Just watch and be amazed at what these guys have accomplished so far with their DIY approach.

It’s not every day you see a Grammy-nominated musician play a sweaty set of throaty, in-your-face rock ‘n roll jams at a tiny hot wing joint, but that’s just what happened Saturday night here in Nashville. Singer Brittany Howard of the Grammy-nominated Alabama Shakes fronted a Nashville supergroup called Thunderbitch, featuring members of Fly Golden Eagle and Clear Plastic Masks, last Saturday night at East Nashville hot chicken joint Ghot Wingz. I was there snapping photos of this bizarre show, all of which can be seen over at the Cream, along with The Spin’s more thorough review of the happenings. In short, I had to mention it because it’s one of those shows that will go down in history, and I’m proud that it happened in the music town I call home!

In other news, though NASA’s Johnson Space Center Students create fun promotional videos for NASA every year, this year’s is quite impressive. Behold “NASA Johnson Style,” their parody of “Gangnam Style.” :

Curiosity's amazing self-portrait from a few weeks ago. Credit: NASA/JPL

Curiosity’s amazing self-portrait from a few weeks ago. Credit: NASA/JPL

It’s been a very crazy week, and I know this may be old news already for some of you, but I had to post about NASA’s announcement on the Curiosity mission findings that caused such an uproar on the internet a few weeks back. For a detailed explanation of what was found and what it means, check out this article on Universe Today. In short, this was the first time all of Curiosity’s instruments had been used in concert together, and the consistency of the results was exciting. It pointed to organic compounds in the Martian soil, but they can’t say for sure that the Carbon in those compounds is of Martian origin. First they have to determine if the Carbon is actually from Mars, and not a contaminant from earth air trapped in the instruments, then they have to determine whether the Carbon is from a biological or non-biological source. There are lots of possibilities that must be ruled out before we will know for sure what’s in the soil, and where it came from. At the announcement, Curiosity Project Scientist John Grotzinger is quoted as saying, “We’re doing science at the speed of science. But we live in a world that’s sort of at the pace of Instagrams. The enthusiasm that we had, that I had, that our whole team has about what’s going on here, I think it was just misunderstood.” That was after he was questioned about the wild speculation that resulted from his comments in an NPR story about a possible “Earth-shaking” discovery by Curiosity. I just love that a NASA scientist compared the speed of science to the “pace of Instagrams.” Instagram and Science! In the same sentence! That must mean science is hip, right? RIGHT?

In other NASA-related news, it was announced on Tuesday that NASA will build and launch in 2020 another Mars rover very similar to Curiosity. While that may not be the most exciting thing to hear, it shows that NASA is building confidence in its abilities to do mind-blowing things like land a nuclear-powered, car-sized roving science lab on another planet with a rocket-powered sky crane. The more we learn about Mars, the closer we get to putting a man there. Who knows, maybe a prime objective of this new mission will be to actually look for signs of past or current life. No mission to Mars yet has actually had that as an objective. For more on this new mission read this article on New Scientist.

While these next two items aren’t necessarily science-y, they are quite awesome:

Curiosity’s amazing self-portrait from a few weeks ago. Credit: NASA/JPL

NASA scientists have created lots of buzz over the past two days because of an NPR story in which Curiosity’s chief investigator John Grotzinger is quoted as saying the latest round of data from Curiosity’s soil analysis instrument is “gonna be one for the history books.” That’s all the information we’ll get, though, at least for a few weeks. While the scientists are very excited about what they’re seeing, they have to run multiple tests and replicate the results in order to be sure the initial interesting result is not a fluke or a glitch. The instrument in question (SAM) looks for organic molecules in the Martian soil, which are the basic building blocks of life as we know it. While none of the instruments on Curiosity can directly detect the presence of life on Mars, they CAN detect basic organics. Even a confirmation of organic molecules would be a huge, MONUMENTAL discovery.

In the past, scientists that have “blown their load” by prematurely announcing exciting results have been burned by it, so this team really wants to be sure of the accuracy and interpretation of their data before going public. One needn’t look further than NASA’s Martian meteorite fossil fiasco in 1996, or their arsenic-based life announcement in 2010 to know that letting your excitement/amazement at your discovery get in the way of un-biased, fact-based analysis can be disastrous.

I certainly hope that the results they’re guarding/confirming point to organic molecules in the soil they’ve analyzed. Curiosity’s findings thus far prove that large amounts of water once flowed on the surface, right where the rover is exploring. It would make sense to me that some form of basic life once existed there. It also wouldn’t surprise me if one day we discover that the DNA from life there mixed with DNA from life here, and that we’re all part Martian, as the idea of panspermia suggests. Those discoveries are likely years or even decades away from happening, but this is still a very exciting time for science!

This will be my last post before Thanksgiving, so have a happy one!

Today I turn 31. Somehow I’ve managed to go this long without knowing that I shared a birthday with the famous astronomer Edwin Hubble (after whom the Hubble Space Telescope is named). This is cool! Even though I also share my birthday with Joe Biden, Mike D (of the Beastie Boys), and Robert F. Kennedy, by far the coolest is Edwin Hubble. If this is not proof of the immensity of my nerdiness, I don’t know what is.

Hubble was a pioneer in the field of extragalactic astronomy. His work, along with that of his colleagues and observations from other astronomers, led to the realization that the universe is continuously expanding. This is know as the metric expansion of space, and is a key component of the Big Bang Theory. Yeah, pretty serious stuff. I feel pretty cool to share a birthday with Mr. Hubble. Were he still alive, he would be 123 years old.

Michael Eades mentioned this yesterday, but I didn’t get a chance to check it out fully until today. The makers of Google Chrome are doing some very cool experiments with their browser, pushing the limits of what’s possible. This scalable, true-to-scale visualization of our home galaxy, centered on our own Sun, is simply phenomenal. It’s one of the coolest things I’ve seen on the internet in quite some time. Bravo, Chrome-people. Bravo. Do yourself a favor and check it out now.

I don’t announce many non-music events on this blog, but this is one big exception: Neil deGrasse Tyson will be speaking at Vanderbilt University’s Langford Auditorium next Tuesday, Nov. 13th. This guy is a total badass. He is one of the few true “real science” celebrities, and he’s also one of my personal heroes. He’s been on TV countless times- hosting shows on PBS, Discovery Channel, Science Channel and more, as well as guest appearances on The Daily Show and Colbert Report many times. I have no idea what he will talk about, but mark my word it will be entertaining and informative. The guy always manages to succeed in convincing the masses that nerd stuff is cool, and is thus an invaluable ambassador of science to the public. I strongly suggest getting your ticket now via any Ticketmaster outlet. They’re only $5 for non-Vandy students, and $10 for general public. (And free if you’re a Vandy student, staff, or faculty member!)

UPDATE: I didn’t realize this event was already sold out! So, still awesome and I hope you got tickets in time!

Here’s the official Vanderbilt link for more info.

See you there!

First of all allow me to direct you to my girlfriend’s blog, and her post about Hurricane Sandy. In short, her parents live a few blocks from the bay on Long Island, and her childhood home flooded with about 2 feet of water last night. So if you’re the praying type, keep her family in your prayers. If you’re the thinking type, keep them in your thoughts.

I discovered this jaw-dropping, mesmerizing US wind map this morning via Discovery News. This fascinating animation is created by streaming realtime wind speed and direction data from the National Digital Forecast Database and feeding it into software that then generates the animation, graphing out the wind as lines across a map of the U.S. The image at the top of this post is a screenshot of the remnants of Sandy. When you visit it, be sure to click on the map and zoom in on the center of circulation. Get really close- it’s truly mesmerizing. Things like this have always fueled my fascination with weather.

And what would any major event, good or bad, be without some sort of meme coming from it? Please direct your browser toward the hilarity of NYC Mayor Bloomberg’s sign interpreter Lydia Calas. I was watching the weather channel last night when this address was airing live, and her face, coupled with Bloomberg’s pathetic attempt at Spanish, provided us some much-needed comic relief in the midst of all the bad news. Literally within minutes of that airing, there was a joke “Miguel Bloombito” twitter account created. I recommend following…