I was told, at a NSF meeting not many months ago, that CERN never makes its data openly available and never would and that US scientists should just plan on getting European collaborators if they want to work on it.
Now, if we just get ESA to start releasing the Rosetta data...
Most of the instruments (e.g. electronics) have a large US contribution. CERN operates the ring, but the instruments are "clients", which are international research teams. That was the vision of CERN after the second world war -- bring leading science to Europe, and make research in Europe attractive. Particle physics was chosen back then.
Yes, that is what I meant (and, even, what I said). To get the data you had to join one of the teams and collaborate with the other scientists in the team. Now, apparently, you don't.
I ran some numbers on this, and concluded it would take a good while to cool Venus - you would have to get rid of the clouds somehow to make the cool-down reasonable, and that means an intervention beyond just the shade. There will be plenty of opportunity for note taking and even PhD theses during the process.
You're forgetting one important thing: any shade large enough to provide sufficient cover for either planet will also effectively be a giant solar sail. Reaching a given location in space would be relatively cheap and easy compared to keeping it there in a useful orientation.
There are two proposed solutions to that
- have a swarm instead of a shade - i.e., lots of little shades, which makes the orbital dynamics (and probably the manufacture) of the system much easier to manage. or - put the shade not at the Lagrange point, but a little bit sunwards, where the solar gravity, planet gravity and the shade radiation pressure give an orbit period matching that of the planet. There, the shade can be pushed by the Sun's radiation pressure and still be in static equilibrium.
Rosetta getting to P67 was much harder energetically than sending a spacecraft to Venus.
You are certainly correct that any of these would be huge engineering tasks, but they are just engineering tasks. They can be done if there is sufficient will.
I was told, at a NSF meeting not many months ago, that CERN never makes its data openly available and never would and that US scientists should just plan on getting European collaborators if they want to work on it.
Now, if we just get ESA to start releasing the Rosetta data...
Well, an Earth sun-shade would need to block at most a few % of the sunshine falling on the Earh, while for Venus (if we want to cool the planet off this millennium) we will need to block all of the Sun's rays for a while, so the engineering is a bit more difficult. Add to this the detail that the Venus Lagrange point 1 is quite a bit further away than the Earth's, and energetically harder to reach, and I think a more reasonable conclusion is that the Earth would be training wheels for Venus, and not vice versa.
I am convinced we will eventually build a sunshade, out at the first (inner) Earth-Sun Lagrange point. It won't help with ocean acidification, but it would make a global thermostat possible.
The Wednesday before Thanksgiving is a busy travel day?!? How did that ever escape our attention? I mean, aside from every DJ on every radio station, and every traffic reporter on every TV station, telling us that every year, how could we possibly find such things out if Google didn't do the heavy lifting?
tt can be baryonic matter, if it is encapsulated in some fashion. I believe your two conditions refer to BBN (not a particularly extreme energy density, BTW) and the Lyman Alpha constraints on Warm Dark Matter (which means it had to drop out of the radiation fluid v ~ c / sqrt(3) pretty early).
Both of these are fulfilled by, e.g., quark nugget dark matter (these would form well before BBN and drop out of the radiation fluid well before needed to fulfill the WDM constraints), as maybe also the recently proposed "macros".
Poisson statistics. I have to wonder if Mr. Haselton has ever heard of the term.
If by some weird alignment of forces I were to become a Judge, and Mr. Haselton presented this to me in a brief, I would try and have him disbarred for abuse of statistical process. I know that the actual legal profession is soft about such abuses, but by God they wouldn't be in my courtroom.
Not to mention that they don't know where the lander is.
I think it is a safe bet it will be found. They have the photos from the surface, they have the CONSERT triangulation, and of course they have a great desire to find it (and the comet isn't that big). It will be found.
Sadly, while the "weight" is very small on the comet, it's mass (and therefore inertia) is substantial. You're not going to blow it over.
I am going to ignore for now any issues of damage from nearby thruster firings.
Rosetta has 24 bipropellant 10 N thrusters and is 2.8 x 2 m, not counting solar panels. Philae is 1 x 1 x 0.8 m. Suppose Rosetta fires a thruster from 3 meters away - Philae is then 1/3 of a radian across, or about 0.1 steradians. Suppose the thruster has a exit angle of 2 pi steradian (i.e., the whole hemisphere away from the spacecraft, which is surely conservative). So, I would expect Philae to experience a force of 10 N x 0.1 / 2 pi ~ 0.2 N. It has a mass of ~ 100 kg, so that would impart a thrust of 2 x 10^-3 m/sec^2. (I am assuming Rosetta has a thruster firing on the opposite side too, so it's not moving.) That is actually greater than the 67/P gravity, so Philae could move. If this were done for say 10 seconds, Philae would have a velocity of ~ 1 cm/sec afterwards and maybe a total flight time of 30 seconds. Now, it wouldn't move far, but it might get to a little flatter terrain and maybe more sunshine.
"It is very unlikely right now. We have 1.5 hours [of sunlight] at less than 1 watt, and 20 minutes of 3 or 4 watts. The lander needs 5 watts to boot....In order to charge the secondary battery, we have to heat it to 0 degrees Celsius. We need about 50-60 watt-hours a day in order to reach 0 degrees and still have daylight left to charge the battery. So it doesn't look that great. What we could hope for is if we are closer to perihelion, near 1 AU, maybe we could have enough energy on our one solar panel, maybe every once in a while"
So, they need 50 watt hours, and they are maybe getting 2. Now, this was before the 30 degree rotation, but I don't think that's going to get them a factor of 20 improvement. Maybe that, plus doing through perihelion, can do it.
I wonder if they couldn't get Rosetta near Philae, and use the reaction jets on Rosetta to move it (i.e., by blowing on it). Philae only weighs about as much as ping-pong ball; it wouldn't take much to move it away from where it is.
While the Philae team is sleeping, nefarious malefactors are busy selling Philae on eBay. It's up to five pounds sterling as I write. Maybe we should wake them up.
1. As the comet approaches the sun, is it likely that the angle of or proximity to the sun will provide enough light to make a difference?
2. I assume we've measured whether Rosetta is rotating, even slightly. Is there a chance that this will help (or hurt) Philae's chances at coming back on line?
3. As the comet gets closer to the sun, I imagine that it will start melting/vaporizing (this being what makes a comet look like a comet in the first place). Since Philae is not firmly anchored (and that might not make a difference in any case), what do we expect to happen, and when?
1.) Maybe.
2.) If you mean Comet P/67, maybe.
3.) Maybe, pretty much anything up to and including ejecting Philae away from the comet for good. As for when, maybe around perihelion (13 August 2015) when activity is highest. Or, maybe before then. Or after then.
They are a big player, because they need a lot of chocolate, and futures help to manage their acquisition prices. Of course, they could try to play with the market, but they'll risk alienating their chocolate eating customers, so it's not clear that this would be in their advantage.
Well, of course. They are the sort of player the futures markets were invented for (they KNOW they will need cocoa in the future, they KNOW more or less how much, why not hedge the price if the opportunity presents itself?). It's just my cynical side wakes up whenever I hear a big futures player start jawboning the market.
It's probably worth mentioning here that Mars, Inc. is one of the big players in the Cocoa futures market. This is not investment advice, but if you invest in cocoa futures based on this article, you would be making a bet based on a story from someone who hopes to make money off of you.
It is an axiom of sales that delays will always mean that some will give up. Whether it's a 5 second wait for a web page to load, or a 5 month wait for a new computer, a delay always means you will lose some customers.
Doesn't the field move around too fast for it to be tightly coupled to the mantle? For example, look at the motion of the magnetic poles - surely hot spots in the mantle are not moving 50 km / year.
As someone who works in Dark Matter, I have to say I am glad that the brand has now reached the point that scientists in other fields appropriate it, apparently purely as a branding mechanism. I mean, I hate to be pedantic, but magma at 3200 C will not be dark.
Slashdot Mirror
I was told, at a NSF meeting not many months ago, that CERN never makes its data openly available and never would and that US scientists should just plan on getting European collaborators if they want to work on it.
Now, if we just get ESA to start releasing the Rosetta data...
Most of the instruments (e.g. electronics) have a large US contribution. CERN operates the ring, but the instruments are "clients", which are international research teams. That was the vision of CERN after the second world war -- bring leading science to Europe, and make research in Europe attractive. Particle physics was chosen back then.
Yes, that is what I meant (and, even, what I said). To get the data you had to join one of the teams and collaborate with the other scientists in the team. Now, apparently, you don't.
I ran some numbers on this, and concluded it would take a good while to cool Venus - you would have to get rid of the clouds somehow to make the cool-down reasonable, and that means an intervention beyond just the shade. There will be plenty of opportunity for note taking and even PhD theses during the process.
You're forgetting one important thing: any shade large enough to provide sufficient cover for either planet will also effectively be a giant solar sail. Reaching a given location in space would be relatively cheap and easy compared to keeping it there in a useful orientation.
There are two proposed solutions to that
- have a swarm instead of a shade - i.e., lots of little shades, which makes the orbital dynamics (and probably the manufacture) of the system much easier to manage.
or
- put the shade not at the Lagrange point, but a little bit sunwards, where the solar gravity, planet gravity and the shade radiation pressure give an orbit period matching that of the planet. There, the shade can be pushed by the Sun's radiation pressure and still be in static equilibrium.
Rosetta getting to P67 was much harder energetically than sending a spacecraft to Venus.
You are certainly correct that any of these would be huge engineering tasks, but they are just engineering tasks. They can be done if there is sufficient will.
The LHC would make an excellent particle beam weapon source, if you should have a starship (generation ship?) big enough to house it.
I was told, at a NSF meeting not many months ago, that CERN never makes its data openly available and never would and that US scientists should just plan on getting European collaborators if they want to work on it.
Now, if we just get ESA to start releasing the Rosetta data...
Well, an Earth sun-shade would need to block at most a few % of the sunshine falling on the Earh, while for Venus (if we want to cool the planet off this millennium) we will need to block all of the Sun's rays for a while, so the engineering is a bit more difficult. Add to this the detail that the Venus Lagrange point 1 is quite a bit further away than the Earth's, and energetically harder to reach, and I think a more reasonable conclusion is that the Earth would be training wheels for Venus, and not vice versa.
I am convinced we will eventually build a sunshade, out at the first (inner) Earth-Sun Lagrange point. It won't help with ocean acidification, but it would make a global thermostat possible.
And, it will be good practice on fixing Venus.
The Wednesday before Thanksgiving is a busy travel day?!? How did that ever escape our attention? I mean, aside from every DJ on every radio station, and every traffic reporter on every TV station, telling us that every year, how could we possibly find such things out if Google didn't do the heavy lifting?
There is a US satellite orbiting the Moon right now, another whose mission just ended, and yet another one 2 years ago.
No, we have not foresworn the Moon.
tt can be baryonic matter, if it is encapsulated in some fashion. I believe your two conditions refer to BBN (not a particularly extreme energy density, BTW) and the Lyman Alpha constraints on Warm Dark Matter (which means it had to drop out of the radiation fluid v ~ c / sqrt(3) pretty early).
Both of these are fulfilled by, e.g., quark nugget dark matter (these would form well before BBN and drop out of the radiation fluid well before needed to fulfill the WDM constraints), as maybe also the recently proposed "macros".
Poisson statistics. I have to wonder if Mr. Haselton has ever heard of the term.
If by some weird alignment of forces I were to become a Judge, and Mr. Haselton presented this to me in a brief, I would try and have him disbarred for abuse of statistical process. I know that the actual legal profession is soft about such abuses, but by God they wouldn't be in my courtroom.
Not to mention that they don't know where the lander is.
I think it is a safe bet it will be found. They have the photos from the surface, they have the CONSERT triangulation, and of course they have a great desire to find it (and the comet isn't that big). It will be found.
Sadly, while the "weight" is very small on the comet, it's mass (and therefore inertia) is substantial. You're not going to blow it over.
I am going to ignore for now any issues of damage from nearby thruster firings.
Rosetta has 24 bipropellant 10 N thrusters and is 2.8 x 2 m, not counting solar panels. Philae is 1 x 1 x 0.8 m. Suppose Rosetta fires a thruster from 3 meters away - Philae is then 1/3 of a radian across, or about 0.1 steradians. Suppose the thruster has a exit angle of 2 pi steradian (i.e., the whole hemisphere away from the spacecraft, which is surely conservative). So, I would expect Philae to experience a force of 10 N x 0.1 / 2 pi ~ 0.2 N. It has a mass of ~ 100 kg, so that would impart a thrust of 2 x 10^-3 m/sec^2. (I am assuming Rosetta has a thruster firing on the opposite side too, so it's not moving.) That is actually greater than the 67/P gravity, so Philae could move. If this were done for say 10 seconds, Philae would have a velocity of ~ 1 cm/sec afterwards and maybe a total flight time of 30 seconds. Now, it wouldn't move far, but it might get to a little flatter terrain and maybe more sunshine.
It wouldn't surprise me if they land Rosetta on the comet toward the end of the mission.
That is indeed under discussion.
From Valerie Lommatsch, an engineer at the Lander Control Center at DLR in Germany :
So, they need 50 watt hours, and they are maybe getting 2. Now, this was before the 30 degree rotation, but I don't think that's going to get them a factor of 20 improvement. Maybe that, plus doing through perihelion, can do it.
I wonder if they couldn't get Rosetta near Philae, and use the reaction jets on Rosetta to move it (i.e., by blowing on it). Philae only weighs about as much as ping-pong ball; it wouldn't take much to move it away from where it is.
While the Philae team is sleeping, nefarious malefactors are busy selling Philae on eBay. It's up to five pounds sterling as I write. Maybe we should wake them up.
1. As the comet approaches the sun, is it likely that the angle of or proximity to the sun will provide enough light to make a difference?
2. I assume we've measured whether Rosetta is rotating, even slightly. Is there a chance that this will help (or hurt) Philae's chances at coming back on line?
3. As the comet gets closer to the sun, I imagine that it will start melting/vaporizing (this being what makes a comet look like a comet in the first place). Since Philae is not firmly anchored (and that might not make a difference in any case), what do we expect to happen, and when?
1.) Maybe.
2.) If you mean Comet P/67, maybe.
3.) Maybe, pretty much anything up to and including ejecting Philae away from the comet for good. As for when, maybe around perihelion (13 August 2015) when activity is highest. Or, maybe before then. Or after then.
Glad I could help clear things up!
If I had to guess, I would bet that sugar or corn syrup is being used as a chocolate extender.
They are a big player, because they need a lot of chocolate, and futures help to manage their acquisition prices. Of course, they could try to play with the market, but they'll risk alienating their chocolate eating customers, so it's not clear that this would be in their advantage.
Well, of course. They are the sort of player the futures markets were invented for (they KNOW they will need cocoa in the future, they KNOW more or less how much, why not hedge the price if the opportunity presents itself?). It's just my cynical side wakes up whenever I hear a big futures player start jawboning the market.
It's probably worth mentioning here that Mars, Inc. is one of the big players in the Cocoa futures market. This is not investment advice, but if you invest in cocoa futures based on this article, you would be making a bet based on a story from someone who hopes to make money off of you.
It is an axiom of sales that delays will always mean that some will give up. Whether it's a 5 second wait for a web page to load, or a 5 month wait for a new computer, a delay always means you will lose some customers.
You would have to be pretty stupid to think that this matters a damn.
Doesn't the field move around too fast for it to be tightly coupled to the mantle? For example, look at the motion of the magnetic poles - surely hot spots in the mantle are not moving 50 km / year.
As someone who works in Dark Matter, I have to say I am glad that the brand has now reached the point that scientists in other fields appropriate it, apparently purely as a branding mechanism. I mean, I hate to be pedantic, but magma at 3200 C will not be dark.