"I've been a Libra my entire life. Now all of the sudden I've been downgraded to a Virgo? Why didn't my previous horoscope warn me about this change?"
Indeed. (Bits and Pieces) Also, "I feel for those who tattooed their sign on their ass. (Not really)"
Showing posts with label Blogs I Like. Show all posts
Showing posts with label Blogs I Like. Show all posts
wallpaper Oh My.
Via Swans on Tea, I found this Flickr collection of sand photos (two pages) by "Mouser NerdBot". Oh my. I need to catch my breath. Now here's the thing I really appreciate: the photographer has done an excellent job of labeling the location and composition of the samples, even, for example, explaining how the garnets below were concentrated from an "ant sand." Check out the enormous original size photos too! 
wallpaper
wallpaper These garnets were extracted from ant sand. Garnet is paramagnetic and can be separated from its surroundings in sand with a strong magnet. These garnets range in size from 1mm to 5mm in diameter. There are presumably larger garnets in the soil in this area, but with ant sand you are limited to things ants can lift and carry.
wallpaper Special Extra Defensive Edition!
Okay, I admit it... I'm a big fan of fiery, provocative and violence-tinged leftist rhetoric. Here's a great example from Circle Jerk at the Square Dance. Click over for #'s 10-1! 15) Why are you blaming conservatives? We didn’t have anything to do with this!
14) Oh, sorry, you actually weren’t blaming conservatives. There’s a lot of that going around.
13) Because, and we want to make this abundantly clear, when we put a crosshairs on someone, we don’t mean they should actually be killed. We mean that they should be eliminated.
12) From office! And not eliminated, no one is saying eliminated. You know, let’s just scrub that from the record. Besides, those weren’t crosshairs. Those were surveyor’s marks, like you’d use when mapping the political landscape or deciding if a bridge should be taken out with an airstrike.
11) Fuck, sorry, we can’t help ourselves with the military analogies. That’s all they are, analogies. You know, Republicans:Godliness::Guns:Freedom.
Top Ten Tuesdays: How are we reacting to the Arizona shooting?
14) Oh, sorry, you actually weren’t blaming conservatives. There’s a lot of that going around.
13) Because, and we want to make this abundantly clear, when we put a crosshairs on someone, we don’t mean they should actually be killed. We mean that they should be eliminated.
12) From office! And not eliminated, no one is saying eliminated. You know, let’s just scrub that from the record. Besides, those weren’t crosshairs. Those were surveyor’s marks, like you’d use when mapping the political landscape or deciding if a bridge should be taken out with an airstrike.
11) Fuck, sorry, we can’t help ourselves with the military analogies. That’s all they are, analogies. You know, Republicans:Godliness::Guns:Freedom.
wallpaper This Made Me Laugh
Titanic Reenactment Club Loses Another 1,300 Members
Doyle Redland reports here, but the headline alone fetched a good guffaw from me.
wallpaper Sand Through the Hourglass: Bits of Geoscience
I'm feeling pretty uninspired. Between staying up too late reading (for several nights running) and what might be a mild cold- which may or may not be part and parcel with the weird, mild headaches that make me feel as if my skull is deforming like a kneaded lump of clay- I just want to go home and go to bed. But I have a backlog of interesting geology and earth science posts I've been meaning to get to, plus a couple more that came up today, so with a minimum of fuss here are some recent bits from the geoblogosphere and related news.
- Silver Fox spent much of the weekend tracking down the original Dutton quote poetically describing Basin and Range as an army of caterpillars crawling north out of Mexico. Like Ron Schott, I'm most familiar with this from the sign at Dante's View in Death Valley, but this has clearly been misquoted many more times than quoted.
- Callan has a slew of mashed-up rocks (what I personally think of as metacrappite, in my own mental categorization of rock groups, without the slightest bit of derogatory intent), in his continuing series on the geology of San Francisco. Also check out the mashed cherts; these are some of the hardest and most competent sedimentary rocks that exist, and to see them folded, spindled and mutilated like taffy should give you a profound respect for the power of the earth.
- Christmas day's EPOD was a stereopair of a beautiful snowflake. I've been meaning to transform this into a wobble-gif, but haven't got to it. I may not. Like I said at the outset...
- Cian at Point Source summarizes her highlights from the recent AGU conference. I'm intrigued by the emphasis I've seen, and not only in her post, on scientists taking a lead role in communicating on their disciplines. As I and numerous others have repeatedly noted, the journalists just aren't getting it done.
- Evelyn at Georneys has a wonderful post about a wonderful map. As familiar as this beautiful bit of cartographic art is to me, I had never realized its importance, nor how recently (alright, okay, I get it, I'm old.) it had been completed. Heartfelt thanks for clarifying, Evelyn.
- Bryan at Hot Topic summarizes a recent interview of James Hansen by Bill McKibben, highlighting the degree of confidence felt among climate scientists regarding global warming, its consequences, and how to ameliorate its effects.
- NatGeo has a gallery of images of what are thought to be collapse pits over lava tubes... on Mars.
- The Guardian has the most complete article I've seen on the reopening of Molycorp's Mountain Pass rare earths mine.
- In a semi-related bit of economic news, Krugman's column today deals with rising commodity prices in a recovering economy, on a finite planet. As I've noted before, geology and economics are much more intimately related than I think most people recognize.
- Also at The Guardian, an article that largely dismisses concerns over the recent news about Cr VI in US drinking water. He makes some valid points, and in my reading, I had already come to much the same conclusion- that the panicky reaction was overblown. However, I think the middle ground is more appropriate here. There's no reason to panic, but his level of dismissiveness is unwarranted as well. This should be of concern, and should be studied more carefully.
- Louisiana will be coming to Oregon to study hurricane storm surges. Huh? Oregon State University has one of the largest wave tanks in the world: The Hinsdale Wave Research Laboratory.
- The explosion and subsequent destruction of the Deepwater Horizon, and the ensuing oil spill, made the new chairman of The House Science and Technology Committee, Ralph Hall (R-Texas), feel all warm and fuzzy inside.
"As we saw that thing bubbling out, blossoming out – all that energy, every minute of every hour of every day of every week – that was tremendous to me," he said. "That we could deliver that kind of energy out there – even on an explosion."
You probably don't want to read that entire article if you would prefer to be optimistic regarding science in the US in the near future.
wallpaper Thanks, Paul
Leave it to a Jewish economist to bring Christmas tears to my eyes. I feel strongly that Christmas and nationalism should be firmly separated, but history is history. It's all too easy for me to be pessimitic and cynical, and it does my heart good when another all-too-frequent (and all too frequently right) pessimist finds reason for optimism.
If this season isn't about finding hope, what is it about?
If this season isn't about finding hope, what is it about?
wallpaper Why I Spend More Time With The Guardian (UK) Than NYT
wallpaper Via Wil Wheaton's Tumblr, and I'm not sure if he compiled this graphic, or if he found it elsewhere. The Guardian's homepage is here, and while the homepage of most news sites is not necessarily the best place to start on a regular basis, it's the best place to start exploring. I read a LOT of different news sources, and The Guardian is my favorite by a long shot, even for US news and commentary.
wallpaper The Age of The Earth
When I talk about my age, or my birthday, or similar topics, I have a base line of a documented day I was born and started breathing the atmosphere. When we talk about the age of a tree, we may be talking about a known planting date or the number of annual growth rings counted near the base. For a manufactured item, it might be known from its container, or make and model from a car, and can often be inferred at least approximately from stylistic changes through the years. In each case, there is a particular point in time that we consider a starting point: birth, first growth, manufacturing.
With something like an entire planet, it gets a little more complicated.
There's a new geotweep, Geologic Time, who is planning to tweet our planet's history as it would occur over the course of time if its ~4.54 billion years were compressed into one calendar year. I signed up to follow the other day because it sounds like a fun exercise and because while, yes, I know a great deal about earth history, I expect there will be any number of facts and tidbits that are new to me.
So when Geologic Time tweeted earlier (in a piece that has now apparently been taken down) that the proto-earth was currently in the process of accretion- planetesimals and rocky material falling together to form the young planet- I tweeted back asking "So what defines when protoplanet becomes 'Earth?'" In other words (I meant) what was the moment, event, or datum of some kind, that geoscientists use to say, "Before this point, it was proto-earth; after this point it was earth." Because there has to be a starting point, right?
Well, the short answer appears to be, "No, not exactly." The accretion process was messy and hot. The proportion of radionuclides- which decay and release more heat- was much higher than today. So there are no datable rocks from our planet's earliest history, and thus nothing on our planet that can be dated. The oldest known rocks are about 4 billion years old, and the oldest known mineral grains are detrital zircons from the Jack Hills of Australia, at about 4.4 billion years. The latter value represents an absolute minimum age for the earth.
My assumption had been that there had been more work done with the lunar samples. I know a lot of work and analysis has been done with those over the last 25 years, and I haven't followed it very carefully. I was also quite aware that the precision of radiometric dating had improved a great deal during that interval. As it turns out though, the planetary midnight of 1/1 is still the same as it was when I was a student: the age of the material that created the earth. Meteorites. I've been reading a bit on this topic since it came up this morning, and I'm not going to go into great detail, but essentially, we have the lower bound of about 4.4 billion years and an upper bound of meteorite ages of about 4.55 billion years. The earth had to have formed between those two times.
Wikipedia did offer one bit of information that was new to me, though. "Nevertheless, ancient Archaean lead ores of galena have been used to date the formation of Earth as these represent the earliest formed lead-only minerals on the planet and record the earliest homogeneous lead-lead isotope systems on the planet. These have returned age dates of 4.54 billion years with a precision of as little as 1% margin for error." So there are two independent and consistent paths that get us to the currently accepted age: meteorites and Archaean galena. One particularly interesting inference that I'm tentatively drawing from all this is that the time from protoplanetary disk to fully accreted planets must have been quite short in the grand scheme of things- maybe ten million to a hundred million years, tops.
The two links included above are both to Wikipedia, but two other sites I found particularly informative were Talk Origins, which appears to be primarily to provide ammunition for those refuting young-earthers, and Palaeos.com, The Hadean Age. The latter provides a description and discussion of what happened when during the first eon of the planet's history, and why we think so. From a distance of billions of years, it makes for fascinating and exciting reading, but I'm glad I wasn't there for it. Both have references from as recently as 2007, so while they may not be utterly current, they have definitely helped me come more up to date than I was a few hours ago.
With something like an entire planet, it gets a little more complicated.
There's a new geotweep, Geologic Time, who is planning to tweet our planet's history as it would occur over the course of time if its ~4.54 billion years were compressed into one calendar year. I signed up to follow the other day because it sounds like a fun exercise and because while, yes, I know a great deal about earth history, I expect there will be any number of facts and tidbits that are new to me.
So when Geologic Time tweeted earlier (in a piece that has now apparently been taken down) that the proto-earth was currently in the process of accretion- planetesimals and rocky material falling together to form the young planet- I tweeted back asking "So what defines when protoplanet becomes 'Earth?'" In other words (I meant) what was the moment, event, or datum of some kind, that geoscientists use to say, "Before this point, it was proto-earth; after this point it was earth." Because there has to be a starting point, right?
Well, the short answer appears to be, "No, not exactly." The accretion process was messy and hot. The proportion of radionuclides- which decay and release more heat- was much higher than today. So there are no datable rocks from our planet's earliest history, and thus nothing on our planet that can be dated. The oldest known rocks are about 4 billion years old, and the oldest known mineral grains are detrital zircons from the Jack Hills of Australia, at about 4.4 billion years. The latter value represents an absolute minimum age for the earth.
My assumption had been that there had been more work done with the lunar samples. I know a lot of work and analysis has been done with those over the last 25 years, and I haven't followed it very carefully. I was also quite aware that the precision of radiometric dating had improved a great deal during that interval. As it turns out though, the planetary midnight of 1/1 is still the same as it was when I was a student: the age of the material that created the earth. Meteorites. I've been reading a bit on this topic since it came up this morning, and I'm not going to go into great detail, but essentially, we have the lower bound of about 4.4 billion years and an upper bound of meteorite ages of about 4.55 billion years. The earth had to have formed between those two times.
Wikipedia did offer one bit of information that was new to me, though. "Nevertheless, ancient Archaean lead ores of galena have been used to date the formation of Earth as these represent the earliest formed lead-only minerals on the planet and record the earliest homogeneous lead-lead isotope systems on the planet. These have returned age dates of 4.54 billion years with a precision of as little as 1% margin for error." So there are two independent and consistent paths that get us to the currently accepted age: meteorites and Archaean galena. One particularly interesting inference that I'm tentatively drawing from all this is that the time from protoplanetary disk to fully accreted planets must have been quite short in the grand scheme of things- maybe ten million to a hundred million years, tops.
The two links included above are both to Wikipedia, but two other sites I found particularly informative were Talk Origins, which appears to be primarily to provide ammunition for those refuting young-earthers, and Palaeos.com, The Hadean Age. The latter provides a description and discussion of what happened when during the first eon of the planet's history, and why we think so. From a distance of billions of years, it makes for fascinating and exciting reading, but I'm glad I wasn't there for it. Both have references from as recently as 2007, so while they may not be utterly current, they have definitely helped me come more up to date than I was a few hours ago.
wallpaper The War On Christmas
wallpaper This topic is, for the most part, one that strikes me as inconsequential and frankly, annoyingly distracting. Celebrate Christmas- or whatever holiday(s)- in the manner that works for you and yours, and let others do the same. However, this post by "Dr. Science" at Obsidian Wings struck me as both amusing and interesting:I recall being taught that one reason Washington attacked on Christmas was specifically because (English) American colonists didn't celebrate the holiday. The German Hessian mercenaries did, though, and so would be hung over and vulnerable when Washington and his army made their surprise attack. In other words, at the time of the Revolution Christmas was unAmerican.There is also some discussion of how our so-called "religious" holidays at this time of year are for the most part usurpations of previously-existing pagan holidays around the solstice, with their symbologies and traditions left largely intact, but with a new narrative superposed.
So again, axial tilt is the reason for the season, but whatever it is you care to celebrate during these shortest days of the year, it's all good as far as I'm concerned. Enjoy the season and the longer days to come.
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