The Leonid meteor shower is on now! Sadly, it is overcast and snowing here, but maybe if you live somewhere good, you can see it? I believe the peak is somewhere around tomorrow night, but obviously it should be good for a few days.
They are expecting near the peak something like a dozen per hour (sadly, not the five hundred per hour that the Facebook event reports). The excellently-named Fluxtimator can give you details.
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Showing posts with label astronomy. Show all posts
Showing posts with label astronomy. Show all posts
Sunday, November 15, 2009
AWoS vol. 1, no. 4 -- Sex, more from LCROSS, a speech gene, curing people with HIV
Rabbits get functional artificial penises
I don't know how much I want to write about this one. Let's just say that with a lack of permanent consequences, John Bobbit-like incidents could end up being more common. An argument against advancing science if I've ever heard one.
Okay, so the implications are important. We're now able to go into a lab, grow tissue that otherwise wouldn't regrow, and implant it into you. They did it with bladders. They've figured out how to do with with hearts (using a neat cartilage shell). Pretty soon, any organ you need with be grown for you. Organ donors won't be a thing of the past, exactly, but they'll only be necessary for emergency purposes. Even then, I can envision hospitals keeping a few samples of each organ in the incubator at all times, just in case.
So yes, not only is there a decent chance that you're not going to die, ever--except perhaps through some horrible meeting with the front end of a moving truck--but if you survive that accident and your penis gets damaged, they can fix it too.
More from LCROSS
There is water on the Moon.
Not very much water, mind, but it's enough to get people excited. There are implications for one day putting a colony/research station up there: if there is water, then we don't have to drag our own up there.
Even more interesting, I think, is the detection of hydrocarbons. They ought to be common in space, forming on the surfaces of the dust grains that get blown out by exploding stars. A few chemical signatures of organic molecules have been detected out in space, but it's hard to say just how much is out there. The dark craters of the Moon, however, act as a sort of trap for all the crud that floats through our solar system, and the detection of hydrocarbons in there means that there must be more floating all around us in space.
It will be interesting to see if the experts can draw any conclusions about hydrocarbons in space from this data. After all, if organic molecules are abundant in space (and it appears that they are), then maybe that will mean life is commonplace throughout the Universe.
Hey, the Moon has oil on it! No wonder the USA bombed it! This particular mission only cost half a billion, though... a far better investment than other, similar endeavours.
A speech gene
Well, sort of. There have been reports in the newspapers about the discovery of a language gene in humans. The truth about FOXP2 is way more interesting. A single change in a single nucleotide... well, read for yourself.
This could be corrected, perhaps, through gene therapy. If only there were a way to insert the proper genes....
Curing people with HIV
No, not curing people who have HIV, but using HIV to cure people (with other diseases).
The reason diseases like HIV and hepatitis B are so bad is that they are caused by a type of virus called a retrovirus. What this means is that the virus actually inserts its own genetic code into the genes of the organism it is infecting. With influenza, for instance, your body eventually kills the invading viruses, and then it is gone. But with retroviruses, even after your immune system has killed the viruses, the code for making more stays inside your cells, meaning that you will infect yourself over and over again.
However, medical science can take advantage of this! Researchers are now using a part of the HIV virus (the insert-into-genes part) to insert genes for making an enzyme called ALD to break down certain fatty acids into patients with a disease also called ALD (which is, of course, caused by an inability to break down fatty acids). This isn't a completely new idea, but it's one of the first major successes I've read about.
The usual method for curing this is bone marrow transplants. Unfortunately, marrow is hard to come by, and because it's intimately involved in the immune system, the body tends to reject it. Inserting new genes gets around these problems.
This bodes well for the future! One can imagine that maybe diabetes will be cured in a similar way, or anemia, or pretty much any other chronic disease. Remember how a few weeks ago they were curing Parkinson's with gene therapy? Remember how five paragraphs ago they discovered what was causing speech problems in certain people?
(Also, maybe we'll one day be able to change our eye colour on the fly, by inserting the right genes in there. Awesome.)
For more on this specific study, read the article linked from this section's title. It's very well written, far better than I can do. But as you read it, think of how far the implications reach....
That's all I have for this week. In the coming days, expect descriptions of a couple of experiments that someone should do, and maybe a little writeup on a chemist who is unknown today, but was one of the greatest in his time. Also, I might translate this into regular English for you, because it's actually pretty neat. (That issue of JPC A has no fewer than ten articles I really want to read, so I might get too distracted....)
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Wednesday, October 21, 2009
Orionid meteor shower!
I completely forgot to mention this, but the Orionid meteor shower is peaking right now. Sadly, it is too cloudy where I am, but if you're awake, go outside and look around. If you missed the peak tonight, do not fret: there have been many meteors all week, and there will probably continue to be many for a few more days.
NASA has some details.
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NASA has some details.
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Sunday, October 18, 2009
AWoS vol. 1, no. 3 -- Space strikes back!, flies, nearly curing Parkinson's, NEPTUNE, bending light, ptransitional pterodactyl, IBEX results
Hi everyone, and welcome to AWoS. There was a swack of good science reported this week, so much that I can't write it all up here. For those reading on the blog page, you may notice a set of links on the right hand side. Those are the main science-related things I read every week. (Well, in addition to some more technical journals.) But if it's mid-week and you're looking for something interesting, they are good places to look! Plus, ScienceNOW, the news arm of Science, has a Facebook group that will send you interesting stuff all week.
Anyway, let's get to the week's happenings!
Last week, I wrote about how we bombed the Moon. It is now being reported that on September 25, space attacked us!
A family in Ontario woke up to find that their car had been vandalized. The hood was smashed in, and there were rock fragments all around. They filed a police report and left it at that. But later, they heard about an exceptionally bright meteor that had been spotted over Ontario and put the facts together.
Unfortunately, they didn't get much rock out of it. A larger chunk could have paid for the repairs.
Two stories involving Drosophila this week.
The first is that mind control took one step closer to reality. Researchers took some fruit flies and labelled their brain cells so that they could read which ones were responsible for associating a particular smell with an electric shock. This is a pretty good feat in itself: they managed to find that only 12 neurons were responsible for this.
Then they gave different flies some chemicals that would activate brain cells. A tricky bit was in releasing those chemicals. You don't want them just floating everywhere, or else every neuron gets activated, so they made them light-sensitive. Now, instead of shocking the fly when the smell was present, they shone light on the proper cells. Amazingly, the chemical/light-treated flies learned to be scared of the smell in the same way that the shocked flies did.
I'm not sure how I feel about this. On the one hand, science fiction teaches us that mind control is bad. On the other hand, if I could learn all there is to know about physics just by injecting chemicals into my brain and shining some light inside my head, that would save me a lot of school work.
The second story is responsible for the funniest picture ever published in an esteemed science journal. I present it here for your amusement.
It was discovered that male fruit flies will mate with anything that is fly-shaped, regardless of species or gender, if the proper chemical cues identifying those characteristics are not there. Females, on the other hand, have no interest in males without the proper chemicals. (A cynic might apply this to human behaviour by replacing "the proper chemicals" with "wads of cash.")
(If you follow the link above, you will see a picture in which they use green fluorescent protein, the creation of which won the Nobel Prize last year.)
For all the talk about animal discoveries, it's sometimes easy to forget how much these studies affect people.
Parkinson's disease is caused when the brain cells responsible for producing dopamine don't function properly. Dopamine is a neurotransmitter, meaning that it helps to send signals between nerve cells (and brain cells). When the body lacks enough dopamine, signals either can't go through or don't go through properly. This leads to muscle tremors, difficulty in moving, and eventually paralysis. There are all sorts of nasty side effects: if you don't blink enough, then your eyes get sores, for instance.
The standard treatment is to give doses of L-DOPA, which the brain converts into dopamine. The problem is that it gets converted everywhere in the body, leading to dopamine excesses, which in turn cause a loss of fine motor control, and eventually cause liver failure (among other problems). Other experimental treatments are more radical, including wire implants in the brain to stimulate the appropriate brain cells.
Parkinson's is a difficult thing to diagnose, in part because there may be many different ways it can occur. Several different mechanisms have been proposed, and from the evidence, it looks like different people may get the disease for different reasons. That makes finding a cure a difficult prospect.
But there is hope. Stéphane Palfi and co-workers gave some monkeys the equivalent of advanced Parkinson's by injecting them with poisons that disabled their dopamine-producing brain cells. Then, they injected three genes responsible for producing dopamine into the monkeys' brains. The monkeys recovered, and don't appear to show any side-effects.
This is not a cure, exactly. Whatever is affecting the original cells is still there. But by having a different path to produce dopamine, the problems associated with the disease disappear. The down side is that you can't control just how much dopamine is being produced in this way, but it looks like the genes given to the monkeys are regulating themselves.
They're currently starting human trials on this. I don't know if the gene therapy needs to be repeated over time, or if it's a one time thing, but this is good news for a lot of people.
A few years ago, I went to a high performance computing conference at which the guest speaker spoke about a project called NEPTUNE. He'd just come back from a trip to place sensors all over the ocean floor near Vancouver Island, and had interesting things to say. Their technical stuff was amazing: a big power line into which new sensors could be plugged as they were developed, live data acquisition, and a variety of instruments that would give unprecedented measurements of the ocean floor, both in terms of geology and biology. Check out some of the images.
I was reminded this week of NEPTUNE by news that the USA's stimulus package included $100 million for the Ocean Observatories Initiative. Good stuff! They're planning on doing around the world what NEPTUNE is doing off Vancouver Island.
We've all heard about the technology to make invisibility a reality, right? You may recall breathless news reports from last year which invoked the name of Harry Potter and an invisibility cloak. Of course, those were massively overblown--the materials used were only created on a small scale. But it is still interesting.
There's a nice little writeup on metamaterials here, if you missed the hype at the time, and a less accurate but easier to read one here. The exciting part, for physics people, is the phrase " in 2000... a metamaterial was demonstrated to have a permittivity and permeability both less than zero." For non-physicists, that means you can do things with light that don't normally happen, like bend it around objects in weird ways, or make magnetic and electric fields go backwards to what you'd normally expect.
The same technology has been used to capture microwave light and focus it on a point to create heat. Big deal, you say, I used to do that with ants and a magnifying glass all the time. True enough, but what's special here is that essentially all the sunlight being captured is turned to heat: with your magnifying glass, you were getting at best 30%. This has big implications for some types of solar energy.
The authors of the article call their discovery a "black hole." Obviously, this isn't a real black hole. What they mean is that they've developed a device from which light at certain frequencies can't escape because of the electromagnetic properties of the material used. For a real black hole, no light can escape because of gravity. Completely different, and just titled like that to catch attention.
More dinosaur news from China: the discovery of Darwinopterus modular. This is a pterosaur from the Middle Jurassic (call it 165 million years ago) which seems to bridge the gap between primitive pterosaurs and the later pterodactyloids in an interesting way.
The article itself has a pretty chart showing the relationships between the various pterosaurs, and if you love these things as much as I do, you will want to browse The Pterosaur Database. Open the pretty chart, if you will. I'm going to refer to it soon.
Darwinopterus is interesting to evolutionary biologists because its existence supports an idea called modular evolution. We all know how evolution works: creatures more adapted to their environment are more likely to reproduce, so the genes that make them more adapted get passed on. The questions that biologists ask relate to how fast evolution occurs. In particular, is it constant through time, with large external pressures and extinction events only contributing by wiping out the weak, or does evolution happen mostly during these events, and very little during stable periods? (Darwin, after whom this dinosaur is named, favoured the idea that most evolution happened quickly, but also knew that it could occur slowly and steadily as well. This is because he was a very great man who made careful observations and thought hard.)
Modular evolution proposes that creatures evolve in modules. One piece gets adapted. Then another. Then another. I don't know what the name for the other kind is, where everything develops simultaneously.
Darwinopterus has the skull (and some other features) of a late pterodactyloid, but the tail of an early pterosaur. If you leave out the skull, then it looks exactly like a reptile in the red group in that pretty chart. If you leave out the tail, it looks exactly like it should be in the blue group. (These are marked by D1 and D2 on the left side of the diagram. The creature itself fits into the purple bracket, number 7).
So it looks like the modular evolution theory holds in this case. The transition from early flying reptiles to late flying reptiles happened one characteristic at a time, probably brought about by abrupt changes in prey or climate. (When I say "abrupt," I mean "over only a couple million years.") It's probably not good to conclude that all evolution occurs this way, though, which is what some of the newspaper articles are implying.
Pterosaurs: they're like Tyrannosaurs in F-14s.
Titles like that are awesome. They sound sciency.
At the edge of our solar system, well beyond Pluto, there is a divider. At this divider, the particles spit off by the Sun (called the solar wind) hit the cold bubble of interstellar space. Our solar system is in a bubble, of sorts. Space is full of gas (the interstellar medium, or ISM), and the solar wind is pushing this gas away. But it can only push so far, and the region where particles from the Sun are stopped is called the heliopause. It's not spherical, but no one's really sure why. In fact, no one's sure about much with regards to this region.
The Interstellar Boundary Explorer (IBEX) was built to study the edges of our solar system. It just returned its first results, and they are strange indeed. It has found a ribbon of dense material in the heliopause. They're attributing this to magnetic fields in the interstellar medium, which means all sorts of exciting new science is there to be done. We know almost nothing about how the ISM works, and this is a great start. (Did you know we don't even know if our galaxy has two or four arms? Weird, huh? We know tons of stuff about distant galaxies, but don't even know what our own looks like.)
IBEX is neat because it uses a special method of observation. Normal telescopes pick up light of various frequencies. However, the ISM consists mostly of neutral atoms, which don't emit light, at least not light that we can see. So IBEX was built to capture energetic neutral atoms, or ENAs. When our solar wind comes into contact with the ISM, some of the slow ISM atoms get accelerated, and some of these get shot toward the centre of the Solar System, where we are.
I'm curious, now. Voyager I is out in this ribbon. Where did the Pioneer craft go? Could something like this, an unexpectedly large number of incoming energetic neutral particles, be the cause of the Pioneer anomaly? They meet the criteria: they would slow a spacecraft's acceleration outwards and are otherwise invisible. It would be interesting to compare IBEX's sky map with the trajectories of the spacecraft affected to see if there is a link (of course, taking into account the effect of the Sun's shielding).
I'm just going to link to this and let you read it. Fractional electron charges? The world gets ever weirder.
That's all for this week! I'm going to make myself an origami pterosaur! Coming during the week: another complaint about Dan Brown's latest book (hint--don't read it if you value your sanity), and a few simple science projects that someone should do.
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Anyway, let's get to the week's happenings!
Space strikes back! (Pre-emptively!)
Last week, I wrote about how we bombed the Moon. It is now being reported that on September 25, space attacked us!
A family in Ontario woke up to find that their car had been vandalized. The hood was smashed in, and there were rock fragments all around. They filed a police report and left it at that. But later, they heard about an exceptionally bright meteor that had been spotted over Ontario and put the facts together.
Unfortunately, they didn't get much rock out of it. A larger chunk could have paid for the repairs.
Fruit flies are the best
Two stories involving Drosophila this week.
The first is that mind control took one step closer to reality. Researchers took some fruit flies and labelled their brain cells so that they could read which ones were responsible for associating a particular smell with an electric shock. This is a pretty good feat in itself: they managed to find that only 12 neurons were responsible for this.
Then they gave different flies some chemicals that would activate brain cells. A tricky bit was in releasing those chemicals. You don't want them just floating everywhere, or else every neuron gets activated, so they made them light-sensitive. Now, instead of shocking the fly when the smell was present, they shone light on the proper cells. Amazingly, the chemical/light-treated flies learned to be scared of the smell in the same way that the shocked flies did.
I'm not sure how I feel about this. On the one hand, science fiction teaches us that mind control is bad. On the other hand, if I could learn all there is to know about physics just by injecting chemicals into my brain and shining some light inside my head, that would save me a lot of school work.
The second story is responsible for the funniest picture ever published in an esteemed science journal. I present it here for your amusement.
It was discovered that male fruit flies will mate with anything that is fly-shaped, regardless of species or gender, if the proper chemical cues identifying those characteristics are not there. Females, on the other hand, have no interest in males without the proper chemicals. (A cynic might apply this to human behaviour by replacing "the proper chemicals" with "wads of cash.")
(If you follow the link above, you will see a picture in which they use green fluorescent protein, the creation of which won the Nobel Prize last year.)
Progress in treating Parkinson's
For all the talk about animal discoveries, it's sometimes easy to forget how much these studies affect people.
Parkinson's disease is caused when the brain cells responsible for producing dopamine don't function properly. Dopamine is a neurotransmitter, meaning that it helps to send signals between nerve cells (and brain cells). When the body lacks enough dopamine, signals either can't go through or don't go through properly. This leads to muscle tremors, difficulty in moving, and eventually paralysis. There are all sorts of nasty side effects: if you don't blink enough, then your eyes get sores, for instance.
The standard treatment is to give doses of L-DOPA, which the brain converts into dopamine. The problem is that it gets converted everywhere in the body, leading to dopamine excesses, which in turn cause a loss of fine motor control, and eventually cause liver failure (among other problems). Other experimental treatments are more radical, including wire implants in the brain to stimulate the appropriate brain cells.
Parkinson's is a difficult thing to diagnose, in part because there may be many different ways it can occur. Several different mechanisms have been proposed, and from the evidence, it looks like different people may get the disease for different reasons. That makes finding a cure a difficult prospect.
But there is hope. Stéphane Palfi and co-workers gave some monkeys the equivalent of advanced Parkinson's by injecting them with poisons that disabled their dopamine-producing brain cells. Then, they injected three genes responsible for producing dopamine into the monkeys' brains. The monkeys recovered, and don't appear to show any side-effects.
This is not a cure, exactly. Whatever is affecting the original cells is still there. But by having a different path to produce dopamine, the problems associated with the disease disappear. The down side is that you can't control just how much dopamine is being produced in this way, but it looks like the genes given to the monkeys are regulating themselves.
They're currently starting human trials on this. I don't know if the gene therapy needs to be repeated over time, or if it's a one time thing, but this is good news for a lot of people.
Ocean observations
A few years ago, I went to a high performance computing conference at which the guest speaker spoke about a project called NEPTUNE. He'd just come back from a trip to place sensors all over the ocean floor near Vancouver Island, and had interesting things to say. Their technical stuff was amazing: a big power line into which new sensors could be plugged as they were developed, live data acquisition, and a variety of instruments that would give unprecedented measurements of the ocean floor, both in terms of geology and biology. Check out some of the images.
I was reminded this week of NEPTUNE by news that the USA's stimulus package included $100 million for the Ocean Observatories Initiative. Good stuff! They're planning on doing around the world what NEPTUNE is doing off Vancouver Island.
Bending light
We've all heard about the technology to make invisibility a reality, right? You may recall breathless news reports from last year which invoked the name of Harry Potter and an invisibility cloak. Of course, those were massively overblown--the materials used were only created on a small scale. But it is still interesting.
There's a nice little writeup on metamaterials here, if you missed the hype at the time, and a less accurate but easier to read one here. The exciting part, for physics people, is the phrase " in 2000... a metamaterial was demonstrated to have a permittivity and permeability both less than zero." For non-physicists, that means you can do things with light that don't normally happen, like bend it around objects in weird ways, or make magnetic and electric fields go backwards to what you'd normally expect.
The same technology has been used to capture microwave light and focus it on a point to create heat. Big deal, you say, I used to do that with ants and a magnifying glass all the time. True enough, but what's special here is that essentially all the sunlight being captured is turned to heat: with your magnifying glass, you were getting at best 30%. This has big implications for some types of solar energy.
The authors of the article call their discovery a "black hole." Obviously, this isn't a real black hole. What they mean is that they've developed a device from which light at certain frequencies can't escape because of the electromagnetic properties of the material used. For a real black hole, no light can escape because of gravity. Completely different, and just titled like that to catch attention.
Ptransitional pterodactyl
More dinosaur news from China: the discovery of Darwinopterus modular. This is a pterosaur from the Middle Jurassic (call it 165 million years ago) which seems to bridge the gap between primitive pterosaurs and the later pterodactyloids in an interesting way.
The article itself has a pretty chart showing the relationships between the various pterosaurs, and if you love these things as much as I do, you will want to browse The Pterosaur Database. Open the pretty chart, if you will. I'm going to refer to it soon.
Darwinopterus is interesting to evolutionary biologists because its existence supports an idea called modular evolution. We all know how evolution works: creatures more adapted to their environment are more likely to reproduce, so the genes that make them more adapted get passed on. The questions that biologists ask relate to how fast evolution occurs. In particular, is it constant through time, with large external pressures and extinction events only contributing by wiping out the weak, or does evolution happen mostly during these events, and very little during stable periods? (Darwin, after whom this dinosaur is named, favoured the idea that most evolution happened quickly, but also knew that it could occur slowly and steadily as well. This is because he was a very great man who made careful observations and thought hard.)
Modular evolution proposes that creatures evolve in modules. One piece gets adapted. Then another. Then another. I don't know what the name for the other kind is, where everything develops simultaneously.
Darwinopterus has the skull (and some other features) of a late pterodactyloid, but the tail of an early pterosaur. If you leave out the skull, then it looks exactly like a reptile in the red group in that pretty chart. If you leave out the tail, it looks exactly like it should be in the blue group. (These are marked by D1 and D2 on the left side of the diagram. The creature itself fits into the purple bracket, number 7).
So it looks like the modular evolution theory holds in this case. The transition from early flying reptiles to late flying reptiles happened one characteristic at a time, probably brought about by abrupt changes in prey or climate. (When I say "abrupt," I mean "over only a couple million years.") It's probably not good to conclude that all evolution occurs this way, though, which is what some of the newspaper articles are implying.
Pterosaurs: they're like Tyrannosaurs in F-14s.
High pressure region in the heliopause, and first direct detection of H and O in the ISM
Titles like that are awesome. They sound sciency.
At the edge of our solar system, well beyond Pluto, there is a divider. At this divider, the particles spit off by the Sun (called the solar wind) hit the cold bubble of interstellar space. Our solar system is in a bubble, of sorts. Space is full of gas (the interstellar medium, or ISM), and the solar wind is pushing this gas away. But it can only push so far, and the region where particles from the Sun are stopped is called the heliopause. It's not spherical, but no one's really sure why. In fact, no one's sure about much with regards to this region.
The Interstellar Boundary Explorer (IBEX) was built to study the edges of our solar system. It just returned its first results, and they are strange indeed. It has found a ribbon of dense material in the heliopause. They're attributing this to magnetic fields in the interstellar medium, which means all sorts of exciting new science is there to be done. We know almost nothing about how the ISM works, and this is a great start. (Did you know we don't even know if our galaxy has two or four arms? Weird, huh? We know tons of stuff about distant galaxies, but don't even know what our own looks like.)
IBEX is neat because it uses a special method of observation. Normal telescopes pick up light of various frequencies. However, the ISM consists mostly of neutral atoms, which don't emit light, at least not light that we can see. So IBEX was built to capture energetic neutral atoms, or ENAs. When our solar wind comes into contact with the ISM, some of the slow ISM atoms get accelerated, and some of these get shot toward the centre of the Solar System, where we are.
I'm curious, now. Voyager I is out in this ribbon. Where did the Pioneer craft go? Could something like this, an unexpectedly large number of incoming energetic neutral particles, be the cause of the Pioneer anomaly? They meet the criteria: they would slow a spacecraft's acceleration outwards and are otherwise invisible. It would be interesting to compare IBEX's sky map with the trajectories of the spacecraft affected to see if there is a link (of course, taking into account the effect of the Sun's shielding).
Fractional Hall Effect in graphene
I'm just going to link to this and let you read it. Fractional electron charges? The world gets ever weirder.
That's all for this week! I'm going to make myself an origami pterosaur! Coming during the week: another complaint about Dan Brown's latest book (hint--don't read it if you value your sanity), and a few simple science projects that someone should do.
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Thursday, October 8, 2009
AWoS Vol. 1, No. 2 -- bombing the Moon, Mercury, a new disease, LHC update, evolution of the ear
Bombing the Moon: LCROSS impact
Out of acceptable land-based targets, the United States this week went boldly where no man has bombed before: the Moon.
The Moon is, of course, the Earth's oldest enemy. Constantly messing up our oceans with its gravity... making our days longer... and who can forget when, following an attack reminiscent of 9/11, it splintered off to form its own society in the bloody revolution of 4 527 000 006 B.C.? So it's about time we got revenge.
On October 9, at 4:30 a.m. PDT, the Lunar Crater Observation and Sensing Satellite (LCROSS for short) performed one of the best experiments ever conceived. The idea is that we want to know if there is water on the Moon. More specifically, we want to know what chemicals make up the dirt under the surface, and the most important of these is water. Adding to the excitement, recent observations from a few orbiting space craft found chemical signatures that hinted there might be water in some of the craters on the Moon's poles.
The bottoms of these craters are permanently dark, and since the Moon has no atmosphere, there's no way for air to carry heat to them. That makes them very cold, which in turn means that water can get trapped under the surface and not escape to space. (Water deposited right on the surface will long since have turned into a gas and escaped into space, but a small layer of dust can lock it in.)
My (admittedly limited) education makes me think that the obervations are mostly of mineral hydroxides, and not water, but since water is everywhere in space, I wouldn't bet against it. I'm not sure if they compared the dark craters with lit craters, but that would probably help. But that's way less fun than what they did.
How do you look under the surface of a rock that is 370 000 km away? Easy... you send up a space revolver with a 2 tonne bullet and shoot it. Then you watch what comes out in the expected big cloud of debris, both with visual observations, and with a variety of more sciency things. Many of us dragged ourselves out into the cold morning air to try to watch this, but sadly, not much happened. They picked a crater that looked promising (changing the target just a couple of days before impact), but the expected dust plume didn't show up. Maybe the Moon is stickier than we thought. Cheese, anyone?
Apparently some of the good telescopes out there can see a bright patch where the bullet hit. The craft itself also crashed (intentionally), which I guess makes this more of a suicide bombing than the overthrow of a Lunarian dictatorship, but I don't know if they're spotted that site yet. There was a tiny blip on the spectrometer which suggests that there might have been water, but more will become known in the next few months.
(I heard so many good jokes about this experiment that I can not include them all here. I just have to say that my friends are awesome, and that I'm glad WTC jokes are finally acceptable to make.)
MESSENGER
In other space news, the MESSENGER craft is currently flying by Mercury for the third time, and it's sending back some nice pictures. One of the really exciting things is the discovery of volcanoes. Go to that site and browse the gallery. Seriously.
What's next for MESSENGER? Well, it's got to slingshot away for a while to lose some more speed, and they they're going to bring it back in and put it into orbit. That will happen in 2011. The path it has taken to get there is pretty complicated--again, check out their web site to see pictures of its travels and a description of what they had to do to get them. It is like the craft finished college and went on a backpacking tour of the inner Solar System.
A New Disease
Well, sort of. There's this thing called Chronic Fatigue Syndrome. It basically means that you're tired all the time. The thing is, no one is really sure that it really exists. Certainly, lots of people are tired. But is it a disease?
New research suggests that for many people, it might be. They took 101 people diagnosed with CFS, and 218 people without, and looked at the differences. What they found was that 67% of the people with CFS had a virus called XMRV (I guess that's 67 people). Only 4% of the healthy people had it (call it 8 people).
That's a striking result! There's definitely a link, and a strong one at that. The question now is: is it the right way? That is, do people get CFS because they have the virus, or are they more likely to get the virus because they have CFS? There's reason to think that the virus is causing the disease: it infects immune cells, which would cause inflammation, a common thing seen in CFS patients. Related viruses in mice lower red cell counts, which would make you tired.
It's going to be cool to see where this goes. There are also cancer research implications here, because the XMRV virus and related viruses are commonly found in prostate cancer patients. (I remember learning about cancer in an organic chem class many years ago, and I asked the professor that since RNA transcription was involved in cancer spreads, if perhaps retroviruses were responsible for some metastic cancers. He said no one knew, but that it was a good idea. Recent studies seem to be supporting this, but nothing is concrete. It looks so obvious to me, so of course it's obvious to biologists, but they still haven't shown it. The point of this story is that it goes to show how difficult this kind of research is.)
The Large Hadron Collider
I was looking this week for some more information about the LHC. For those who don't know, the LHC is the biggest science experiment ever. There's an enormous tunnel in Switzerland, and they're going to fire some protons through it at ludicrous speed, crash them together (insert Princess Diana joke), and watch what comes out (another Diana joke).
It takes enough energy to do this that they've had to reconfigure the European power grid, and they have to run at times when people aren't using a lot of electricity.
It first started up about a year ago. And ended a year ago. A short circuit blew out a big chunk of it, and it's taken a long time to repair everything and make sure it doesn't happen again. It looks like a mid-November restart is in the works, though.
The way I found out about the restart date is through an article that said someone working on it possibly had terrorist ties. Why do we even care about that? There is incredible science about to happen, and we're worried that one worker among thousands might be linked to a terrorist (or linked to a guy who is linked to a terrorist)? That drives me nuts.
Evolution of the ear
In the early Cretaceous (say, 120 million years ago), mammals were just getting a foothold in the world. The first marsupials were evolving, and Tyrannosaurs did not yet roam the Earth. Birds were starting to split off from dinosaurs. We're talking a mere 20 million years after Archaeopteryx. Flowering plants were just coming into being. In general, life was exciting.
With dinosaurs eating everything in sight, how did mammals make it through the next 55 million years to the Cretaceous-Tertiary extinction, where the dinosaurs died? By being good at hearing! The mammalian ear is pretty amazing. You have these tiny little bones, all set up to amplify sound in a big way. Sometimes, creationists will point to the ear because they have a crayon jammed in there. Other times, they will point to it as evidence for their cause, saying it is too complicated to have evolved (and therefore a god or gods--but not a spaghetti monster--created us).
Well, now we know just how it evolved! We had a good idea already, but now there is concrete evidence. (That is a fossil pun, by the way.) Maotherium was discovered in China, with fossils so good that they found fur imprints. Awesome!
What does it tell us about hearing? The word we are looking for here is heterochrony. It means "different timing," and is used in biology to say that the time in your life at which you developed some organ (or whatever developmental thing you want to talk about) is different from that of someone else, typically an ancestor. The best example is the axolotl, which additionally exhibits something called neoteny, meaning that it never grows up. The ancestors of axolotl did grow up, which makes it ever more interesting. It's like evolution is going backwards! The best part of axolotl is that you can stress it out and make it grow up. It's seriously the best animal ever, you guys.
Okay, enough axolotl loving. Ears. Ears.
Ears. Modern mammals have this bit of cartilage called Meckel’s cartilage, which holds the ear bones to the jaw as they develop. Soon before or after birth, this cartilage dissolves, leaving a functional (and sensitive) ear. Maotherium had Meckel's cartilage, but it didn't disappear! It instead turned into bone, fusing the jaw to the ear. This is heterochrony: the structure was always there, but it develops in a different way now.
So Maotherium probably wasn't great at hearing by modern standards, except that it could put its chin on the ground and hear very well. Snakes hear like this, and our common ancestor likely had a rudimentary form of it. Snakes evolved to specialize in hearing those ground vibrations, while mammals who could hear with their heads in a compromising position (in the air, while eating leaves or whatever) had an evolutionary advantage. Maotherium heard things better than the animals around it. And then there was an animals whose Meckel's cartilage didn't harden into bone. It had an advantage. And then one came along with a modern ear. And eventually, here we are! (I'm not sure if we're directly descended, but it's close enough.)
The original paper is here if you can get access. It's pretty neat.
That's it for this week. I'm off to look at pictures of axolotls! Tune in next week: same science time, same science channel.
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AWoS Vol. 1, No. 1 -- Nobel Prize week, Saturn, a distant ancestor, and man-made northern lights
I like Nobel Prize week more than I like my birthday (which I do not celebrate). More than Christmas (though I love buying gifts). More than a fat, rare steak--but less than that same steak wrapped in bacon. But it should be clear that I like it a lot.
Mmm... bacon....
I just spent an hour on the Nobel Prize web site reading and thinking about an old acceptance lecture, that of Dudley Herschbach. This is why I love Nobel week. It reminds me that people are smart. Lots of smart people are described as doing lots of smart things, and also it has the Otto Stern cigar story.
I'm going to do these out of order, because it will take less explaining this way. Trust me.
Ada Yonath, Venkatraman Ramakrishnan, and Thomas Steitz
(I put Ada Yonath's name first because she's a woman, and only four women have won a chemistry Nobel. My thesis advisor will, at the slightest provocation, tell you all about how Rosalind Franklin got screwed out of her share of the Prize with Watson and Crick, who discovered DNA. Franklin was dead at the time they got the prize, so she was ineligible. But I agree that she should get a lot more recognition than she does. Yonath was also the first person to get a crystal structure for a ribosome, so that's a good non-sexist reason to put her first.)
The chemistry prize frequently goes to advances in what should more properly be called biology. Or maybe that's just the physical chemist in me talking. Anyway, that's what happened this year, but since it involves my favourite molecule in the world, I am not too upset. Having never taken biology, I only learned about this in my fourth year of chemistry, in a "hah hah we'll review some stuff to start the semester" class. It was probably the greatest thing I learned that entire year, and that was the year I learned that you could wrap steaks in bacon.
So here's how life works. You have some DNA, which contains a bunch of chemicals in a certain order (they call this the genetic code). The DNA is divided up into parts, and when you stick some other chemicals on to hold them together, you get what are called chromosomes. The most famous are the X and Y chromosomes: women have two Xs, while men have one X and one Y. But DNA doesn't make you live, really. Chromosomes are what you get from your parents... not genes, as is commonly said. I mean, the genes are on the chromosomes, and sometimes spread across a few chromosomes, but it's really the chromosomes that are being passed on. (You got 23 from your mom, and 23 complementary ones from your dad, unless you have a genetic disease of some sort.)
Your body runs on proteins, which are these enormous (relatively speaking) molecules that actually do stuff, like make a nerve send a signal, tell your immune system to kill invaders, or make delicious bacon-wrapped steaks oh-so-nutritious. The trouble is in turning DNA into proteins. Imagine you have a long, thin strip of paper with holes punched in it. These holes, taken in groups, can be read as letters. That's DNA. Now, you're given a roomful of this paper and told to build the house that they describe. How are you going to do that?
The first step is to figure out what's written on the paper. You need a translator. Now, you could do this by hand, but you're smarter than that. You go buy yourself an old computer that can read ticker tapes, put a bit of the paper in, and tell it to read. In addition, you program the computer to figure out where every letter starts and ends, and to put it all into words, which it then makes sure are forward and not backward. Oh, and when the thing says, "get a hammer," the computer should scour your room for scrap metal, melt it down, carve a handle, and make you a hammer.
This is what a ribosome does! Holy cow! You have billions of these little computers inside your body, doing impossibly complex things!
So what the winners this year did was make crystals of these biological computers/factories, and use those to figure out what they look like. Why is this useful? Well, every species has roughly the same parts inside each cell, but there are a few small differences. In particular, bacteria have a slightly different ribosome than people do. (A few billion years of divergent evolution will do that.) So if you can make chemicals that destroy bacterial ribosomes, but not human ones, you can give it to a person and kill the bacteria in that person, but not the person. Hurrah! So knowing what the ribosome looks like means you can make computer models of it, and use those to develop antibiotics to cure sick people. Of course, there are many other uses, and we haven't discovered them all yet.
Science: making your life better since the day you were born.
Elizabeth Blackburn, Jack Szostak,and Carol Greider
Back in the 1970s, DNA had just been figured out, and molecular biology was getting exciting. Read the thing on chromosomes I wrote before. I told you I chose this order for a reason.
So how do you get a new set of chromosomes into a cell? How do you make copies of your chromosomes to pass onto your children? There is something called DNA replication, and it's done by a bunch of proteins, led by one called DNA polymerase. DNA comes in a pair of strands wound together, so to copy it, the DNA polymerase has to unwind the strand, copy it bit by bit, and wind it back up. It goes something like this:
1. find a "primer," which is a bit of DNA or RNA that splits the wound DNA strand
2. wait for the primer to attach, then attach to the primed DNA
3. loop:
3.1 look at the next bit of information
3.2 copy it and attach it to the last copied one (or the primer, at the start)
3.3 proofread and correct if necessary
4. when done, break off
Simple, right? Well, the hard part is the "when done" part. The end parts have a repeating sequence of 6 chunks of information, called a telomere. DNA polymerase can only work in one direction, and replication stops when a telomere sequence is reached (kind of), so the end telomeres get chopped off. If this happens enough times, then your chromosomes start to get too short to work. Not good!
How does the body overcome this? These researchers found a protein called telomerase. Blackburn found the repeating sequence that we now called a telomere. Szostak found out that chromosome fragments break down, and the two of them figured out that it was because of the telomeres. Then, Blackburn and Greider found out why: an enzyme called telomerase. Telomerase seeks out DNA and adds telomeres to the end.
This is important because telomeres are a big part of getting old. You age because your telomeres are getting shorter. They're also a big part of cancer: cancerous cells can divide quickly without dying because they create a lot of telomerase. And right now, people are curing cancer using this fact.
Charles Kao, Willard Boyle, George Smith
There are two different discoveries here, but the Nobel committee lumped them into a single prize. They're more engineering things than pure physics, but still useful.
Kao got half the prize for figuring out how to make fibre optics practical. Are you using the Internet? Then you are probably getting information that has been passed through fibre optics.
Fibre optics work by bending and reflecting light within a glass tube. Ever looked at your living room window at night and seen your reflection? Well, that reflection is how fibre optics work. Without going into it too much, Kao figured out that the reason early fibre optics weren't very good was that the glass wasn't pure enough. He did some calculations to show that it was possible, and then lobbied the right scientists to get it done.
Boyle and Smith worked at Bell Labs. I don't know how many Nobel Prizes have gone to people who've worked there, but I bet it's more than a couple. Great things come from Bell Labs. They invented the CCD, which is the electronic sensor used in your digital camera and cell phone, and also in most astronomical imaging equipment and modern medical imaging.
Think of a CCD like an ice cube tray, and the light coming in as rain drops. If light is brighter in one place, the hole in the tray corresponding to that will get full faster. Every once in a while, someone comes along and sucks up the water with a straw, and in that way figures out how the rain is distributed. That corresponds to light and dark areas in your photograph. Colour is just done by having three ice cube trays: one accepts only red water, one only green, and one only blue.
This is my favourite headline ever.
The Spitzer telescope, which observes in the infrared, has found a big ring that's farther out from Saturn than any other. They figure that it's due to material being kicked off one of the moons. The cool thing is that the material from this ring is coating one of the other moons, making the side of it going into the wind (so to speak) dark, like if you threw a snowball through a smoky room.
At the moment, Saturn is at equinox, so all the other rings are pretty much invisible from Earth. However, this new ring is tilted a bit, so it's clearly visible... well, if you can see infrared light.
I like this one because the discovery was made 17 years ago, but it was kept quiet until just now, so that good science could be done. It wasn't secret, but most of the people studying the fossil waited until the others were ready to publish, and they did it all together.
The main fossil described in these papers is named Ardipithecus, and is the oldest fossil from which we're descended since the split that lead to chimpanzees. It's 4.4 million years old: the famous Lucy (an Australopithecus) is a youthful 3.2 million, while the chimp split was about 6 million years ago.
The fossil is cool because it shows that there was a lot of evolution between the split and now. The most used example is that Ardipithecus has hands that aren't like any living great ape, but there are many more things like this.
The most important part is that we can't think of chimpanzees as being what our ancestors looked like. We never looked like chimps. Instead, we were something quite different, and became specialized to several different environments since. (A few million years from now, maybe our ancestors will have extra fingers so that they can type faster, and a few million after that, they will have none because they don't need to type any more.)
This one's interesting because there's a conspiracy theory that the HAARP (High Frequency Active Auroral Research) program is using radio waves to control people's minds. Enough said on that. (The web site has a wicked cautionary statement, though.)
Basically, they have a radio station. A super-powered radio station. And way up north, there are lots of charged particles floating around in the atmosphere, because of the way the Earth's magnetic field directs particles from the Sun around. So they turn up the juice and start cranking their funky beats out to the radios of the reindeer and polar bears, and something cool happens.
When you bring a lot of ions close together, they collide, and electrons get bumped around, emitting light in the process. That's how the northern lights work: all the ions get close together near the pole, collide, and give off light. The radio waves have a magnetic field, and that directs the ions close enough to make this happen on command.
Recently, they've more than tripled their power output. What it means is that you can now see the light from the experiments. Before, they probably used radar or something to "see" it. (I admit, I skimmed that section.)
Their antenna shoots radio waves, which are, well, waves. So you get a pattern in the sky that looks like you just threw a rock into a pond. But what they found was that there were streaks coming out from the centre, like if your rock hit a bunch of beavers and they all started swimming away from the middle. They did some math and figured out that their radio waves were now powerful enough to cause some of the neutral (non-ionic) molecules to ionize... which meams those regions could light up, too.
So they're not just using the ions already in the atmosphere any more. They're making their own! I don't know if it's direct ionization (knocking electrons off with each radio wave hit), or if there is something more complicated going on, but I bet it's a bit of both. (If they need someone good with molecular dynamics for modelling work.... *waves hand wildly in the air*)
That's the end of our flagship issue! I hope you enjoyed it. Suggestions are much appreciated. I'm thinking of maybe breaking future issues into smaller segments, stealing pictures to go with articles, and a couple other things.
Until next time, stay sciency!
**************************************************
Mmm... bacon....
I just spent an hour on the Nobel Prize web site reading and thinking about an old acceptance lecture, that of Dudley Herschbach. This is why I love Nobel week. It reminds me that people are smart. Lots of smart people are described as doing lots of smart things, and also it has the Otto Stern cigar story.
I'm going to do these out of order, because it will take less explaining this way. Trust me.
Nobel Prize in Chemistry
Ada Yonath, Venkatraman Ramakrishnan, and Thomas Steitz
(I put Ada Yonath's name first because she's a woman, and only four women have won a chemistry Nobel. My thesis advisor will, at the slightest provocation, tell you all about how Rosalind Franklin got screwed out of her share of the Prize with Watson and Crick, who discovered DNA. Franklin was dead at the time they got the prize, so she was ineligible. But I agree that she should get a lot more recognition than she does. Yonath was also the first person to get a crystal structure for a ribosome, so that's a good non-sexist reason to put her first.)
The chemistry prize frequently goes to advances in what should more properly be called biology. Or maybe that's just the physical chemist in me talking. Anyway, that's what happened this year, but since it involves my favourite molecule in the world, I am not too upset. Having never taken biology, I only learned about this in my fourth year of chemistry, in a "hah hah we'll review some stuff to start the semester" class. It was probably the greatest thing I learned that entire year, and that was the year I learned that you could wrap steaks in bacon.
So here's how life works. You have some DNA, which contains a bunch of chemicals in a certain order (they call this the genetic code). The DNA is divided up into parts, and when you stick some other chemicals on to hold them together, you get what are called chromosomes. The most famous are the X and Y chromosomes: women have two Xs, while men have one X and one Y. But DNA doesn't make you live, really. Chromosomes are what you get from your parents... not genes, as is commonly said. I mean, the genes are on the chromosomes, and sometimes spread across a few chromosomes, but it's really the chromosomes that are being passed on. (You got 23 from your mom, and 23 complementary ones from your dad, unless you have a genetic disease of some sort.)
Your body runs on proteins, which are these enormous (relatively speaking) molecules that actually do stuff, like make a nerve send a signal, tell your immune system to kill invaders, or make delicious bacon-wrapped steaks oh-so-nutritious. The trouble is in turning DNA into proteins. Imagine you have a long, thin strip of paper with holes punched in it. These holes, taken in groups, can be read as letters. That's DNA. Now, you're given a roomful of this paper and told to build the house that they describe. How are you going to do that?
The first step is to figure out what's written on the paper. You need a translator. Now, you could do this by hand, but you're smarter than that. You go buy yourself an old computer that can read ticker tapes, put a bit of the paper in, and tell it to read. In addition, you program the computer to figure out where every letter starts and ends, and to put it all into words, which it then makes sure are forward and not backward. Oh, and when the thing says, "get a hammer," the computer should scour your room for scrap metal, melt it down, carve a handle, and make you a hammer.
This is what a ribosome does! Holy cow! You have billions of these little computers inside your body, doing impossibly complex things!
So what the winners this year did was make crystals of these biological computers/factories, and use those to figure out what they look like. Why is this useful? Well, every species has roughly the same parts inside each cell, but there are a few small differences. In particular, bacteria have a slightly different ribosome than people do. (A few billion years of divergent evolution will do that.) So if you can make chemicals that destroy bacterial ribosomes, but not human ones, you can give it to a person and kill the bacteria in that person, but not the person. Hurrah! So knowing what the ribosome looks like means you can make computer models of it, and use those to develop antibiotics to cure sick people. Of course, there are many other uses, and we haven't discovered them all yet.
Science: making your life better since the day you were born.
Nobel Prize in Physiology or Medicine
Elizabeth Blackburn, Jack Szostak,and Carol Greider
Back in the 1970s, DNA had just been figured out, and molecular biology was getting exciting. Read the thing on chromosomes I wrote before. I told you I chose this order for a reason.
So how do you get a new set of chromosomes into a cell? How do you make copies of your chromosomes to pass onto your children? There is something called DNA replication, and it's done by a bunch of proteins, led by one called DNA polymerase. DNA comes in a pair of strands wound together, so to copy it, the DNA polymerase has to unwind the strand, copy it bit by bit, and wind it back up. It goes something like this:
1. find a "primer," which is a bit of DNA or RNA that splits the wound DNA strand
2. wait for the primer to attach, then attach to the primed DNA
3. loop:
3.1 look at the next bit of information
3.2 copy it and attach it to the last copied one (or the primer, at the start)
3.3 proofread and correct if necessary
4. when done, break off
Simple, right? Well, the hard part is the "when done" part. The end parts have a repeating sequence of 6 chunks of information, called a telomere. DNA polymerase can only work in one direction, and replication stops when a telomere sequence is reached (kind of), so the end telomeres get chopped off. If this happens enough times, then your chromosomes start to get too short to work. Not good!
How does the body overcome this? These researchers found a protein called telomerase. Blackburn found the repeating sequence that we now called a telomere. Szostak found out that chromosome fragments break down, and the two of them figured out that it was because of the telomeres. Then, Blackburn and Greider found out why: an enzyme called telomerase. Telomerase seeks out DNA and adds telomeres to the end.
This is important because telomeres are a big part of getting old. You age because your telomeres are getting shorter. They're also a big part of cancer: cancerous cells can divide quickly without dying because they create a lot of telomerase. And right now, people are curing cancer using this fact.
Nobel Prize in Physics
Charles Kao, Willard Boyle, George Smith
There are two different discoveries here, but the Nobel committee lumped them into a single prize. They're more engineering things than pure physics, but still useful.
Kao got half the prize for figuring out how to make fibre optics practical. Are you using the Internet? Then you are probably getting information that has been passed through fibre optics.
Fibre optics work by bending and reflecting light within a glass tube. Ever looked at your living room window at night and seen your reflection? Well, that reflection is how fibre optics work. Without going into it too much, Kao figured out that the reason early fibre optics weren't very good was that the glass wasn't pure enough. He did some calculations to show that it was possible, and then lobbied the right scientists to get it done.
Boyle and Smith worked at Bell Labs. I don't know how many Nobel Prizes have gone to people who've worked there, but I bet it's more than a couple. Great things come from Bell Labs. They invented the CCD, which is the electronic sensor used in your digital camera and cell phone, and also in most astronomical imaging equipment and modern medical imaging.
Think of a CCD like an ice cube tray, and the light coming in as rain drops. If light is brighter in one place, the hole in the tray corresponding to that will get full faster. Every once in a while, someone comes along and sucks up the water with a straw, and in that way figures out how the rain is distributed. That corresponds to light and dark areas in your photograph. Colour is just done by having three ice cube trays: one accepts only red water, one only green, and one only blue.
Giant ring around Saturn found
This is my favourite headline ever.
The Spitzer telescope, which observes in the infrared, has found a big ring that's farther out from Saturn than any other. They figure that it's due to material being kicked off one of the moons. The cool thing is that the material from this ring is coating one of the other moons, making the side of it going into the wind (so to speak) dark, like if you threw a snowball through a smoky room.
At the moment, Saturn is at equinox, so all the other rings are pretty much invisible from Earth. However, this new ring is tilted a bit, so it's clearly visible... well, if you can see infrared light.
An early ancestor of humans
I like this one because the discovery was made 17 years ago, but it was kept quiet until just now, so that good science could be done. It wasn't secret, but most of the people studying the fossil waited until the others were ready to publish, and they did it all together.
The main fossil described in these papers is named Ardipithecus, and is the oldest fossil from which we're descended since the split that lead to chimpanzees. It's 4.4 million years old: the famous Lucy (an Australopithecus) is a youthful 3.2 million, while the chimp split was about 6 million years ago.
The fossil is cool because it shows that there was a lot of evolution between the split and now. The most used example is that Ardipithecus has hands that aren't like any living great ape, but there are many more things like this.
The most important part is that we can't think of chimpanzees as being what our ancestors looked like. We never looked like chimps. Instead, we were something quite different, and became specialized to several different environments since. (A few million years from now, maybe our ancestors will have extra fingers so that they can type faster, and a few million after that, they will have none because they don't need to type any more.)
Artificial northern lights
This one's interesting because there's a conspiracy theory that the HAARP (High Frequency Active Auroral Research) program is using radio waves to control people's minds. Enough said on that. (The web site has a wicked cautionary statement, though.)
Basically, they have a radio station. A super-powered radio station. And way up north, there are lots of charged particles floating around in the atmosphere, because of the way the Earth's magnetic field directs particles from the Sun around. So they turn up the juice and start cranking their funky beats out to the radios of the reindeer and polar bears, and something cool happens.
When you bring a lot of ions close together, they collide, and electrons get bumped around, emitting light in the process. That's how the northern lights work: all the ions get close together near the pole, collide, and give off light. The radio waves have a magnetic field, and that directs the ions close enough to make this happen on command.
Recently, they've more than tripled their power output. What it means is that you can now see the light from the experiments. Before, they probably used radar or something to "see" it. (I admit, I skimmed that section.)
Their antenna shoots radio waves, which are, well, waves. So you get a pattern in the sky that looks like you just threw a rock into a pond. But what they found was that there were streaks coming out from the centre, like if your rock hit a bunch of beavers and they all started swimming away from the middle. They did some math and figured out that their radio waves were now powerful enough to cause some of the neutral (non-ionic) molecules to ionize... which meams those regions could light up, too.
So they're not just using the ions already in the atmosphere any more. They're making their own! I don't know if it's direct ionization (knocking electrons off with each radio wave hit), or if there is something more complicated going on, but I bet it's a bit of both. (If they need someone good with molecular dynamics for modelling work.... *waves hand wildly in the air*)
That's the end of our flagship issue! I hope you enjoyed it. Suggestions are much appreciated. I'm thinking of maybe breaking future issues into smaller segments, stealing pictures to go with articles, and a couple other things.
Until next time, stay sciency!
**************************************************
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