Score
Title
382
AskScience Panel of Scientists XVII
7363
I’ve read that when caterpillars are in their cocoons, they dissolve completely into goo; no original parts survive in the butterfly. How is the butterfly made from the goo? Is there an embryo that grows and uses the goo like a yolk sac? Or does the goo somehow arrange itself into new body parts?
104
How sustainable is our landfill trash disposal model in the US? What's the latest in trash tech?
16392
With all this fuss about net neutrality, exactly how much are we relying on America for our regular global use of the internet?
54
If tooth decay is just caused by the bacteria feeding and producing acid, would a person that just used listerine have the same dental health as a person that brushed without flossing?
16
Does boiling water in a low pressure atmosphere still kill pathogens?
16
My doctor says that chemotherapy works by specifically targeting rapidly-dividing cells, which is how it works to fight cancer and also why it has the side effects that it does. But how does it “know” which cells are rapidly dividing? And how rapidly is “rapidly”?
8
How mixable are different types of plastic? Like PET and HDPE?
15
How are isotopes used in nuclear physics Experiments isolated?
848
In 1996 NASA announced 'evidence of primitive life on early Mars'. In 2000, a second report supported the thesis. What happened next?
3
How are the needles for Atomic Force Microscopes made, and how can the tip be smaller than the atoms they are manipulating? What are their limitations?
8
How are the triple(or more) parachutes commonly seen on capsules returning from space kept apart?
3
What makes a laser shine in a straight line?
82819
Help us fight for net neutrality!
1
How do scientists determine the weight of huge (extinct) animals?
2
what's the difference between ZW and XY chromosomes, how did they evolve, and why are ZW organisms homogametic for males where XY organisms are heterogametic?
4
What's the current state of AIDS? Is it still basically a death sentence, or is it manageable? What are the consequences of getting AIDS nowadays?
1
What happened to the Global Cooling scare of the 1980's?
0
If a pipe was run from space straight into the ocean would water run up it and flow into space?
2
Can animals understand human body language like laughing or smiling?
2
Lithium batteries are being developed to power cars in response to the decline in fossil fuels, but will lithium eventually run out as well?
1
Question from my 4 year old sister, do other animals also get "Boogers"?
1
Is there any short-term geothermal or atmospheric effect that is caused by the sun heating one "side" of the earth at a time?
14
Could an electric vehicle stand a chance in a racing event?
23
If there is an ocean below the ice surface of Europa, is the ice shell buoyant? Geologically supported? Or is it kept in place by the distribution of gravity?
1
Is there a mathematical relationship between Moire patterns, Chladni plate vibration patterns, and the pattern formed by rings when making different cuts from wood?
2
Would readers of character based languages (e.g Chinese) experience dyslexia differently since they don't use strings of letters?
3
How to calculate eigenvalues in the Kirchhoff's thin plate model?
27
Do all individual atoms in a solid emanate their own blackbody radiation?
14
Is there anywhere other than Earth in the Solar system where you could see a total solar eclipse and/or total lunar eclipse equivalent?
4
How did we get solid matter from light? How did Photons and Electrons create solid matter in the early ages of the universe when everything was insanely hot?
3
Since the event at CERN that proved the existence of Higgs bosons/Higgs field, can we now see this event happen regularly now we know ‘where’ to look?
8
Why does turning on an electric blender in the kitchen cause my HD antenna signal to go out in a different room?
6
Can the human body survive breathing pure oxygen at lower pressures?
14
When beryllium-16 decays and produces 2 neutrons simultaneously, what happens to that dineutron?
6
How do we know the earth’s core is super hot and why is it so?
1
How does the pressure of the vacuum of space affect the ISS?
11184
From my kid: Can you put a marshmallow on a stick out into space and roast it with the sun?
3
Given that cerebrospinal fluid flows around the structures of the brain, would messenger chemicals from synaptic activity in one area be passed to, and alter synaptic activity in other regions of the brain?
9
How do we know what the tonsil does?
2
In a compound with an alkene and an alkyne, which would ozone cleave in an oxidative cleavage reaction?
1164 cantgetno197 The wavelength of light that comes out of an X-ray laser is in the tens of nanometers, versus in the hundreds of nanometers that comes out of a "regular" (i.e. visible wavelength) laser and versus the hundreds of millions of nanometers that came out of their fore bearer the maser (Microwave-aser). But, at the end of the day, it's all light and all the same basic mechanism.
87 antimony121 To perhaps add a few more details to the main difference mentioned already (energy of the light being produced) *and explain differences in the process of creating x-ray beams: It might first be useful to point out that laser light, unlike that from a light bulb, is coherent, so all the light waves are in phase with one another which is a direct result of how the energy is produced. In standard lasers, this energy is coming from the relaxation of excited electrons (excited by some mechanism, pretty much always deliberate to ensure the highest probability for the relaxation of the energy you're wanting, using something like a flash lamp, electric current, or even another laser, depending on the specific type of laser). The relaxation gives off the light you're looking for. Once this happens in one electron, that light prompts a neighboring, similarly excited electron to do the same with the nice bonus of doing so perfectly in phase with the original stimulating light/photon (this is the "stimulation" and "amplification," since you're getting two for the price of one, in the acronym that makes the word laser -- Light Amplification by the Stimulated Emission of Radiation). Since this means you need to have the electrons excited to an energy at least as high as the energy you want to get out of the laser, and for a relatively long amount of time as far as atomic/molecular excitations are concerned, the higher the lasing energy, the harder the process is to control and produce. When you reach the energy of x-rays, this is so much that it will usually just ionize whatever is being excited, stripping off the electron completely, which kills your shot at the whole coherent light production process. The first x-ray lasers got around this by using just the high energy electrons themselves, produced in [linear accelerators](https://portal.slac.stanford.edu/sites/lcls_public/aboutlcls/Pages/About-LCLS.aspx), using magnetic field to giggle them back an forth fast enough to give of coherent x-rays. More recently (and using technology I'm still trying to get my head around fully that totally blows my mind), [table-top x-ray](https://jila.colorado.edu/kmlabs/research/articles/attosecond-nonlinear-optics) lasers are coming out that are made by -- in the absolute simplest of analogies that doesn't completely capture the process -- almost but not quite ionizing atoms by kind of slingshotting electrons around their nuclei in such a way that the angular acceleration it gains has the x-ray energy you want, which it then gives off as it relaxed back to its regular orbit around the nucleus. Again, the details of this one I'm still catching up on so I hopefully I'm not too off on these points and it still makes some kind of sense. Not sure how much you already knew about laser physics, so sorry if this is overly in-depth and telling you stuff you already knew. I didn't mention some of the other aspects that will affect the type of light you get out (such as pulsed lasers vs. CW that are a single wavelength emitted constantly), but I'd be happy to further elaborate if you're interested.
11 LeWorgen The frequency is higher i.e. the energy in an X-ray laser is higher (E=hv, where E is the energy of the photon, h is the plank constant and v is the frequency), therefore more dangerous than a regular (visible-light) laser.
9 BeardySam Lots of good answers here so I'm just throwing in a fact not a lot of people know: the US 'Star Wars' program under Reagan was a space-bourne x-ray laser, using a nuclear bomb to pump the states of the lasing medium.
3 XJindosh Awesome, thanks! Is the difference down to the geometry of the magnets? Or is there other differences between the two? (I.e. input beam properties) I'd imagine for the broadband source you'd need an electron pulse with a larger range of kinetic energies, whilst the converse would be true for the narrow band output? Which leads me to think it's more than the geometry of the magnets....
1161 0 cantgetno197 The wavelength of light that comes out of an X-ray laser is in the tens of nanometers, versus in the hundreds of nanometers that comes out of a "regular" (i.e. visible wavelength) laser and versus the hundreds of millions of nanometers that came out of their fore bearer the maser (Microwave-aser). But, at the end of the day, it's all light and all the same basic mechanism.
89 0 antimony121 To perhaps add a few more details to the main difference mentioned already (energy of the light being produced) *and explain differences in the process of creating x-ray beams: It might first be useful to point out that laser light, unlike that from a light bulb, is coherent, so all the light waves are in phase with one another which is a direct result of how the energy is produced. In standard lasers, this energy is coming from the relaxation of excited electrons (excited by some mechanism, pretty much always deliberate to ensure the highest probability for the relaxation of the energy you're wanting, using something like a flash lamp, electric current, or even another laser, depending on the specific type of laser). The relaxation gives off the light you're looking for. Once this happens in one electron, that light prompts a neighboring, similarly excited electron to do the same with the nice bonus of doing so perfectly in phase with the original stimulating light/photon (this is the "stimulation" and "amplification," since you're getting two for the price of one, in the acronym that makes the word laser -- Light Amplification by the Stimulated Emission of Radiation). Since this means you need to have the electrons excited to an energy at least as high as the energy you want to get out of the laser, and for a relatively long amount of time as far as atomic/molecular excitations are concerned, the higher the lasing energy, the harder the process is to control and produce. When you reach the energy of x-rays, this is so much that it will usually just ionize whatever is being excited, stripping off the electron completely, which kills your shot at the whole coherent light production process. The first x-ray lasers got around this by using just the high energy electrons themselves, produced in [linear accelerators](https://portal.slac.stanford.edu/sites/lcls_public/aboutlcls/Pages/About-LCLS.aspx), using magnetic field to giggle them back an forth fast enough to give of coherent x-rays. More recently (and using technology I'm still trying to get my head around fully that totally blows my mind), [table-top x-ray](https://jila.colorado.edu/kmlabs/research/articles/attosecond-nonlinear-optics) lasers are coming out that are made by -- in the absolute simplest of analogies that doesn't completely capture the process -- almost but not quite ionizing atoms by kind of slingshotting electrons around their nuclei in such a way that the angular acceleration it gains has the x-ray energy you want, which it then gives off as it relaxed back to its regular orbit around the nucleus. Again, the details of this one I'm still catching up on so I hopefully I'm not too off on these points and it still makes some kind of sense. Not sure how much you already knew about laser physics, so sorry if this is overly in-depth and telling you stuff you already knew. I didn't mention some of the other aspects that will affect the type of light you get out (such as pulsed lasers vs. CW that are a single wavelength emitted constantly), but I'd be happy to further elaborate if you're interested.
11 0 LeWorgen The frequency is higher i.e. the energy in an X-ray laser is higher (E=hv, where E is the energy of the photon, h is the plank constant and v is the frequency), therefore more dangerous than a regular (visible-light) laser.
9 0 BeardySam Lots of good answers here so I'm just throwing in a fact not a lot of people know: the US 'Star Wars' program under Reagan was a space-bourne x-ray laser, using a nuclear bomb to pump the states of the lasing medium.
3 0 XJindosh Awesome, thanks! Is the difference down to the geometry of the magnets? Or is there other differences between the two? (I.e. input beam properties) I'd imagine for the broadband source you'd need an electron pulse with a larger range of kinetic energies, whilst the converse would be true for the narrow band output? Which leads me to think it's more than the geometry of the magnets....