Serpentinization requires water to seep through rocks and to get oxidized. If this new interpretation of the existence of methane is indeed correct, then it clearly implies the existence of the large body of water in the recent past (or at present).
So in either way it turns out, this is a cool finding.
/i do have to wonder sometimes, though, how narrow-minded those astrophysicists/planetary scientists are, as opposed to those geologists who have to work really hard to match their theory/experiment with the abundant amount of sample data points on earth.
Well, well, no surprise here. "Free" wifi surely attracts the cheap folks who either cannot afford or will not shell out $50+ for high-speed bandwidth.
Supersonic means just that -- particles moving faster than the LOCAL speed of sound. It varies slightly at a distance, as you might imagine.
Don't think too much. Generally speaking there is the presence of a "shock" where a supersonic flow turns into subsonic one. That's why you hear about these words often when talking about heliopause.
The termination shock is basically where the wind of the sun meets "the wall" -- as known as interstellar medium.
You know about the solar wind. It's basically a stream of particles flowing out of the Sun's atmosphere at a supersonic speed. The particles would cruise radially out of the Sun and go on and on and on...until it meets a clump of gas associated with semi-primodial stuffs that the Sun and other neighboring stars were made out of. Imagine that the Sun is sitting in a void of space (the emptiness was due to the solar wind sweeping out the material around it).
Anyway, as the particles in the solar wind nears the wall, the particles in the solar wind begins to "feel" the presence of a wall. It's like a wind hitting a building and twirl near the wall of the building. A similar thing happens here and the sensors on board Voyager can sense the motion of these particles "twirling" around. In this case, these particles are slowing down and that's what Voyager I has detected.
As for the precise timing? I don't think there is a clear signature of the "termination" point. It might have been in 2003 or in Dec 2004. In the astronomical standpoint, the distinction is, I believe, not so meaningful.
Phew. That's alot to write. I'd better go to bed now.
Well well, just imagine a chunk of water floating inside a space station. Initially it'd be more or less spherical at rest. But once an astronaut pokes on it, it starts vibrating in many different modes...but its vibration eventually dies down, thanks to the air molecules surrounding the water bubble.
Basically the same thing is happening to the Earth. But in this case, the air (atmosphere) is thinner and there is nothing outisde (vacuum). So dumping the vibration energy takes time. Eventually the energy would turn into heat via friction, however.
If this turns out to be a real thing, it'd be a good news for Emergency Medical Service personnel.
Sterlization is one of the key steps to prevent infection to worsen one's injury. H2O2 etc. is great, but these are somewhat too acidic sometimes and too cumbersome to carry around.
Imagine a case where you climb mountains in cold winters. You have cold foot injuries like trench foots. If one can carry around simple medical material to help sterlize, better yet, help it heal faster, it'd be very nice indeed.
I still have to see (1) how cheap the material is and (2) how portable the medium would be.
This satellite is actually interesting since it may hold a key on how to retain a gap in the A-ring. It has to do with this small body of a satellite perturbing the neighboring, smaller dusts and removing them from the region effectively.
Somelike that can be studied numerically (n-body problems) to prove the ring's composition, etc. A nice test case for n-body problem.
[I really should be moderating today but...oh well.]
I'd usually agree with your sentiment. But this finding is rather important and scientifically useful (for some, not really for me).
The significant thing is this: this moon, how small it is, may regulate the way a gap in the A-ring evolves (or stay clear of smaller rocks),
The effect of the moon's gravity is small, but not small enough to be ignored by the material nearby. Some smart guys can run some numerical analysis to study what the rings are made of, and how a single massive (relatively) body can perturb its surrounding smaller particles.
Would it make a better material for building elevated highways and bridges? It needs to tolerate both weak and strong vibrations (small cars and trucks) all day and night. It needs to be water-proof that cracks don't become serious issue, either.
Hmm, in a few thousand years, the magnetic pole may be so off that the good ol' coordinate system may be redefined / out of existence? And the plate moves, too. Not to mention the Sun zips through interstellar place to make it even more obscure about where this event actually took place?
If he's still alive, maybe we should ask him. Given the changes in scope technology since the HST was designed, perhaps his answer would surprise you more than me?
Not a chance (and he's passed away). But Lyman would agree with me. Or at least his students have.
Furthermore, you need to check the details of your information more accurately. Ground telescopes with adoptive optics (VLT, Gemini, and Subaru, etc.) do well in the NIR/MIR regime. It's because atmospheric disturbance is more manageable / relatively simpler to characterize and to compensate for at these wavebands. But they can't do that in visual that well. There, the HST has no competition at today's technology [*]
[*] There is a speckle method, however, to beat the disturbance. Not trivial, though.
That said, if you are going for IR, ground telescopes are often the right kind of place. Here I don't mean to negate the justification for the JWST. In space, there is no atmosphere; hence the background noise (no air to emit IR) is low and also there is no IR bandpass that is obscured by air, either. In short, the JWST benefits from the excellent sensitivity (super plus for cosmological studies).
I sense you may be a fellow in my field (probably a student). You really need to get some facts streighten out before you get out there and try to impress someone else to give you a job.
ps. I don't necessarily support the HST servicing missions (except for the one which needs for deorbit). I'm all for in support of developping other space missions with the money saved for a SMOV.
No. Gravity affects every body. But there is a difference between gravitationally affected and gravitationally bound.
The sign of co-moving is a pretty good indicator that the system can be bounded (but you can't exclude a possibility that these stars are merely in the same association and the direction of their motion is coincidental). To establish that the planet is bound to the brown dwarf, one needs to examine its orbital path, which requires more data points in future.
One small note: "co-moving" and "orbiting" are not the same thing. They have enough evidence to suggest that they are co-moving. But that doesn't necessarily prove (nit-pick, I know) that they orbit each other. That'll be proven in follow-up observations.
although part of the HST's range does go into the UV, it primarily goal was always the visible light spectrum.
Sigh. If Lyman Spitzer heard you say something like that, he'd ripped your head out of your body...
Run the optical tracing based on the specification of the HST. You'll notice that the best optical image of the HST is attained at 2800AA. The original concept of a space telescope was to have a high-spatial/spectral resolution imager/spectrograph in UV and visible light. At least that's what I thought when working with the HST instrument!
You've got the concept of the JWST more or less correct. But the JWST was treated as a followup of the HST by the scientists and engineers at the Space Telescope Institute. Not many other professionals would agree with your view. I certainly do not.
The key issue is whether the suspected planet is at the same distance as the brown dwarf [and I assume that we know accurately enough about the distance to the brown dwarf].
Since these stars are co-moving, it is very likely that these objects are either formed out of the same primodial materials (ie., these stars are in the same association) or gravitationally bound (i.e., the suspect planet revolves around the brown dwarf). The evidence of the co-moving alone doesn't necessarily prove that the stars are bounded by gravity, but the accuracy of their measurements probably suggest that it's pretty darn likely. Further studies are necessary to derive the orbits for sure.
Anyway, once you establish the distance, one can figure out its true brightness of the suspected planetary object. That helps you narrow down the mass of that object (which is nailed down to be about 5x the mass of Jupiter). Combined with the "color" information of the object, these scientists makes a conclusion that this is indeed a planet.
By the way, these objects are separated by the whooping 0.7 arcseconds. Its apparent seperation is 5 times greater than the apparent size of Pluto or something like that. You don't really need use the Hubble for studying something like this.
One correction: not all of astronauts are test pilots, though many take up flying before or after becoming an astronaut. It is true that the flying experience is a definite plus to become an astronaut.
First, the James Webb Space Telescope is not a replacement for the Hubble. The JWST is designed for IR astronomy; the HST is primarily for UV astronomy. They are complementary, but by no means the JWST is a replacement for the HST.
Slashdot Mirror
Leo and Inez Wong have nothing to do with it (yet), I swear.
Serpentinization requires water to seep through rocks and to get oxidized. If this new interpretation of the existence of methane is indeed correct, then it clearly implies the existence of the large body of water in the recent past (or at present).
/i do have to wonder sometimes, though, how narrow-minded those astrophysicists/planetary scientists are, as opposed to those geologists who have to work really hard to match their theory/experiment with the abundant amount of sample data points on earth.
So in either way it turns out, this is a cool finding.
You'd be surprised how the real cheap folks (college students, etc.) priortize.
I have a laptop with a wireless card, too. But I never paid my $$$ for it. It just sometimes comes with a job.
Well, well, no surprise here. "Free" wifi surely attracts the cheap folks who either cannot afford or will not shell out $50+ for high-speed bandwidth.
Supersonic means just that -- particles moving faster than the LOCAL speed of sound. It varies slightly at a distance, as you might imagine.
Don't think too much. Generally speaking there is the presence of a "shock" where a supersonic flow turns into subsonic one. That's why you hear about these words often when talking about heliopause.
If that's not funny, I don't know what would.
The termination shock is basically where the wind of the sun meets "the wall" -- as known as interstellar medium.
You know about the solar wind. It's basically a stream of particles flowing out of the Sun's atmosphere at a supersonic speed. The particles would cruise radially out of the Sun and go on and on and on...until it meets a clump of gas associated with semi-primodial stuffs that the Sun and other neighboring stars were made out of. Imagine that the Sun is sitting in a void of space (the emptiness was due to the solar wind sweeping out the material around it).
Anyway, as the particles in the solar wind nears the wall, the particles in the solar wind begins to "feel" the presence of a wall. It's like a wind hitting a building and twirl near the wall of the building. A similar thing happens here and the sensors on board Voyager can sense the motion of these particles "twirling" around. In this case, these particles are slowing down and that's what Voyager I has detected.
As for the precise timing? I don't think there is a clear signature of the "termination" point. It might have been in 2003 or in Dec 2004. In the astronomical standpoint, the distinction is, I believe, not so meaningful.
Phew. That's alot to write. I'd better go to bed now.
A lump of water floating in a vacuum would still come to rest, but just very slightly slower.
/. handle...
A lump of water can't exist in a vacuum, but that's aside the point. I just want to comment that you're right on other points.
I always adjust my level of details in my comments, knowing that I am not always reaching out the informed physics professors or students.
leading to a branch of science called Helioseismology.
And some people wondered where I got my
Well well, just imagine a chunk of water floating inside a space station. Initially it'd be more or less spherical at rest. But once an astronaut pokes on it, it starts vibrating in many different modes...but its vibration eventually dies down, thanks to the air molecules surrounding the water bubble.
Basically the same thing is happening to the Earth. But in this case, the air (atmosphere) is thinner and there is nothing outisde (vacuum). So dumping the vibration energy takes time. Eventually the energy would turn into heat via friction, however.
If this turns out to be a real thing, it'd be a good news for Emergency Medical Service personnel.
Sterlization is one of the key steps to prevent infection to worsen one's injury. H2O2 etc. is great, but these are somewhat too acidic sometimes and too cumbersome to carry around.
Imagine a case where you climb mountains in cold winters. You have cold foot injuries like trench foots. If one can carry around simple medical material to help sterlize, better yet, help it heal faster, it'd be very nice indeed.
I still have to see (1) how cheap the material is and (2) how portable the medium would be.
Yes.
I'm repeating myself here (see my post below)...
This satellite is actually interesting since it may hold a key on how to retain a gap in the A-ring. It has to do with this small body of a satellite perturbing the neighboring, smaller dusts and removing them from the region effectively.
Somelike that can be studied numerically (n-body problems) to prove the ring's composition, etc. A nice test case for n-body problem.
[I really should be moderating today but...oh well.]
I'd usually agree with your sentiment. But this finding is rather important and scientifically useful (for some, not really for me).
The significant thing is this: this moon, how small it is, may regulate the way a gap in the A-ring evolves (or stay clear of smaller rocks),
The effect of the moon's gravity is small, but not small enough to be ignored by the material nearby. Some smart guys can run some numerical analysis to study what the rings are made of, and how a single massive (relatively) body can perturb its surrounding smaller particles.
Wait a second...didn't ROTSE detect an optical afterglow first in 1999?
/a?
ROTSE's first detection of optical afterglow
Would it make a better material for building elevated highways and bridges? It needs to tolerate both weak and strong vibrations (small cars and trucks) all day and night. It needs to be water-proof that cracks don't become serious issue, either.
Does it really matter if you adblock it? I have www.primidi.com blocked completely and when I click it only loads its text, not anything ad-like.
Or am I naive to think that's not good enough to stop letting someone use slashdot for making profit?
Hmm, in a few thousand years, the magnetic pole may be so off that the good ol' coordinate system may be redefined / out of existence? And the plate moves, too. Not to mention the Sun zips through interstellar place to make it even more obscure about where this event actually took place?
If he's still alive, maybe we should ask him. Given the changes in scope technology since the HST was designed, perhaps his answer would surprise you more than me?
Not a chance (and he's passed away). But Lyman would agree with me. Or at least his students have.
Furthermore, you need to check the details of your information more accurately. Ground telescopes with adoptive optics (VLT, Gemini, and Subaru, etc.) do well in the NIR/MIR regime. It's because atmospheric disturbance is more manageable / relatively simpler to characterize and to compensate for at these wavebands. But they can't do that in visual that well. There, the HST has no competition at today's technology [*]
[*] There is a speckle method, however, to beat the disturbance. Not trivial, though.
That said, if you are going for IR, ground telescopes are often the right kind of place. Here I don't mean to negate the justification for the JWST. In space, there is no atmosphere; hence the background noise (no air to emit IR) is low and also there is no IR bandpass that is obscured by air, either. In short, the JWST benefits from the excellent sensitivity (super plus for cosmological studies).
I sense you may be a fellow in my field (probably a student). You really need to get some facts streighten out before you get out there and try to impress someone else to give you a job.
ps. I don't necessarily support the HST servicing missions (except for the one which needs for deorbit). I'm all for in support of developping other space missions with the money saved for a SMOV.
Good by Titan, and thanks for all the memories.
No. Gravity affects every body. But there is a difference between gravitationally affected and gravitationally bound.
The sign of co-moving is a pretty good indicator that the system can be bounded (but you can't exclude a possibility that these stars are merely in the same association and the direction of their motion is coincidental). To establish that the planet is bound to the brown dwarf, one needs to examine its orbital path, which requires more data points in future.
One small note: "co-moving" and "orbiting" are not the same thing. They have enough evidence to suggest that they are co-moving. But that doesn't necessarily prove (nit-pick, I know) that they orbit each other. That'll be proven in follow-up observations.
although part of the HST's range does go into the UV, it primarily goal was always the visible light spectrum.
Sigh. If Lyman Spitzer heard you say something like that, he'd ripped your head out of your body...
Run the optical tracing based on the specification of the HST. You'll notice that the best optical image of the HST is attained at 2800AA. The original concept of a space telescope was to have a high-spatial/spectral resolution imager/spectrograph in UV and visible light. At least that's what I thought when working with the HST instrument!
You've got the concept of the JWST more or less correct. But the JWST was treated as a followup of the HST by the scientists and engineers at the Space Telescope Institute. Not many other professionals would agree with your view. I certainly do not.
The key issue is whether the suspected planet is at the same distance as the brown dwarf [and I assume that we know accurately enough about the distance to the brown dwarf].
Since these stars are co-moving, it is very likely that these objects are either formed out of the same primodial materials (ie., these stars are in the same association) or gravitationally bound (i.e., the suspect planet revolves around the brown dwarf). The evidence of the co-moving alone doesn't necessarily prove that the stars are bounded by gravity, but the accuracy of their measurements probably suggest that it's pretty darn likely. Further studies are necessary to derive the orbits for sure.
Anyway, once you establish the distance, one can figure out its true brightness of the suspected planetary object. That helps you narrow down the mass of that object (which is nailed down to be about 5x the mass of Jupiter). Combined with the "color" information of the object, these scientists makes a conclusion that this is indeed a planet.
By the way, these objects are separated by the whooping 0.7 arcseconds. Its apparent seperation is 5 times greater than the apparent size of Pluto or something like that. You don't really need use the Hubble for studying something like this.
One correction: not all of astronauts are test pilots, though many take up flying before or after becoming an astronaut. It is true that the flying experience is a definite plus to become an astronaut.
First, the James Webb Space Telescope is not a replacement for the Hubble. The JWST is designed for IR astronomy; the HST is primarily for UV astronomy. They are complementary, but by no means the JWST is a replacement for the HST.