By the way... for those interested, I highly recommend JPL's introduction to the Basics of Space Flight. It starts off very simple but by the time you get to the end you'll have a reasonable knowledge of the various concepts and systems involved in satellites and space probes.
Freefall is also an excellent source of information;);)
The rocket doesn't go straight up to its geostationary position - indeed if it did go straight up it wouldn't achieve orbit at all, because it's only stationary in that it stays above a fixed point on the Earth's surface... the rocket still needs massive angular velocity. If you just go straight up from a point you don't get that. Kind of hard to visualise, I'm sorry my explanation isn't too clear... imagine you jumping into the air. (ignoring air resistance) You're no longer being pulled along and given angular velocity by contact with the ground, but you still have momentum in a straight line so you move very little with respect to the surface. If gravity were to suddenly disappear you wouldn't hover while the Earth spun beneath you, you'd carry on at a tangent instead. Point is, going straight up doesn't get you to orbit even if it's geostationary.
Besides all that, geostationary orbits must be above the equator, so it has to go a fair way south from Florida.
I'm not an expert at all on this, but I think that with geostationary satellites they usually put it in a parking orbit first which is roughly circuilar at a few hundred km altitude, then burn another stage for "geostationary transfer orbit", which has its perigee in LEO and apogee at the desired position. When the rocket reaches the full 35790km, the motor is fired again to raise the perigee and achieve a circular geostationary position.
The timing of all this is critical if you want to achieve geostationary orbit above a given point, although I suppose they could potentially leave it in parking orbit for a few hours until it was the right position for geostationary transfer.
You can't schedule a launch based on TV times. Even Judge Judy cannot trump the laws of physics... to get the satellite in the right spot in its orbit there is a narrow launch window.
There's a difference between going to Mars and going to the rest of the galaxy. We aren't going to have interstellar colonies in the next hundred, probably next thousand years - the technology is so far behind that it's just not possible, no matter what the funding. I ran the numbers a while back and just to get a 10-ton probe to Alpha Centauri within two centuries would take all the energy the Earth uses in a decade, and that's without counting a lot of inefficiencies.
On the other hand, setting up a colony on Mars is quite possible and practical, and in my view a good idea both from the philosophical/aesthetic point of view and because sooner or later, we're going to have a nuclear war or an asteroid impact or a nanotech accident or a bioengineered disease. Having all our eggs in one basket is plain stupid when we have the capability to go.
Now sell all that to the public and you'll be on to a winner.
Wow! Those are amazing photos! Does anyone know if that's a fish-eye lens enhancing the curvature of the Earth? I wouldn't have thought it would be so visibly curved at 60km altitude..
It doesn't actually require 3 people. 1 pilot and sandbags (or whatever) equivalent to two other people are also allowed.
Presumably Rutan will have designed for this weight. It's probably just a matter of filling up the tanks all the way, but they'll be doing more testing than just "kick the tires and light the fires".
If we discover any intellegent life by looking from Earth, it has to be around our level or more advanced, to change the environment enough for us to notice. Even from say 1 AU away, you'd have a job telling Earth apart from a planet without humans.
Of course looking at radio waves is a possibility.
Please show me a fusor that can get trillions of neutrons per second. That's 5 orders of magnitude better than the best amateur effort, and 4 better than the professionals.
I've fallen asleep every night (more or less) for the last six months since I got 802.11g with my laptop right next to my head on my bedside table. I don't wake up with a headache.
Microwaves do not cause biological damage unless you have hundreds of watts of them, and that's just heat.
It's really not physically possible. The frequency is too low to cause any ionising effects, leaving the only possible effect as heating, and I think that you get much more heating from say the hard drive in your laptop than you do from the 1W WiFi.
Is "not for retail" legally binding at -all-? What about the "Multipack - do not sell separately"? IANAL but I don't see why the companies have any right to dictate that.
Actually the opposite is true - the colder a planet is, the more atmosphere it can hold on to. This is because the thermal velocity, that is the average speed of the gas molecules, depends on the temperature and increases on hotter planets or moons. If it's above the escape velocity, bye-bye atmosphere. Incidentally this is why the Earth has no hydrogen or helium in its atmosphere, because those lighter gases need less heat to reach high thermal velocities, and they just go zipping off into space.
Some chemist correct me here, but I don't think there's any potential energy in just the hydrocarbons. You need oxygen to burn them in as well, which Titan doesn't have. I can't think of a way to extract energy from them alone.
Basically, the radiation and lack of sunlight (Titan is very cold) pretty much rule out the possibility of life. Spectra from Earth-based telescopes show no signs of oxygen in the atmosphere - this isn't required for basic life but I think the consensus is that anything advanced enough to have developed intelligence needs a lot of energy and that has to come from respiration with oxygen. People talk about other forms of life based on silicon etc, but I'm pretty sure that no serious scientists think that's a possibility. ET life may not be 'as we know it' but we should know it when we see it, and we aren't seeing it on Titan.
You'd use a Farnsworth fusor as a neutron source? I don't think they produce enough neutrons for significant activation. It is possible to build a fission reactor from natural U metal but I don't think it's easy at all!
I've also worked with the greats on issues like interplanetary climate (my speciality), working with Angstrom winner Richard Hoagland on Europan climate systems.
This is pretty laughable. Ad homoneim it may be, but Richard Hoagland is pretty much the worst offender in pseudoscience.
Distance really matters very little in spaceflight. Delta-V is what counts, and the amount needed to reach Venus from the Earth's surface isn't a lot different (within 20%) to that needed to reach Mars, or the Moon, because the vast majority is used up in getting to Earth orbit. It would take less time to reach Venus than Mars but you pretty much have to spend several months on-planet anyway to wait for them to be in the right orbital positions again for the return journey... and an extra 3 months in a spacecraft is no big deal technologically.
Furthermore you'd need a lot more rocket fuel for the ascent from Venus due to its substantially heavier gravity than Mars. All this is beside the point because designing something to survive Venus surface temperature for more than a few hours is just about impossible - you somehow have to build a refrigerator that can get its hot/radiative side to at least 700C and have the whole not lot melt. The pressure isn't so much of a challenge but the astronauts wouldn't be able to venture outside in anything short of a submarine, and what's the point in doing that?
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Freefall is also an excellent source of information ;) ;)
Besides all that, geostationary orbits must be above the equator, so it has to go a fair way south from Florida.
I'm not an expert at all on this, but I think that with geostationary satellites they usually put it in a parking orbit first which is roughly circuilar at a few hundred km altitude, then burn another stage for "geostationary transfer orbit", which has its perigee in LEO and apogee at the desired position. When the rocket reaches the full 35790km, the motor is fired again to raise the perigee and achieve a circular geostationary position.
The timing of all this is critical if you want to achieve geostationary orbit above a given point, although I suppose they could potentially leave it in parking orbit for a few hours until it was the right position for geostationary transfer.
You can't schedule a launch based on TV times. Even Judge Judy cannot trump the laws of physics... to get the satellite in the right spot in its orbit there is a narrow launch window.
On the other hand, setting up a colony on Mars is quite possible and practical, and in my view a good idea both from the philosophical/aesthetic point of view and because sooner or later, we're going to have a nuclear war or an asteroid impact or a nanotech accident or a bioengineered disease. Having all our eggs in one basket is plain stupid when we have the capability to go.
Now sell all that to the public and you'll be on to a winner.
Wow! Those are amazing photos! Does anyone know if that's a fish-eye lens enhancing the curvature of the Earth? I wouldn't have thought it would be so visibly curved at 60km altitude..
Presumably Rutan will have designed for this weight. It's probably just a matter of filling up the tanks all the way, but they'll be doing more testing than just "kick the tires and light the fires".
Hmm.. wouldn't it be cool if ETI was discovered, and (e.g.) the Catholic Church decided to send a mission? Now there's a source of funding!
Er, what? The material for the Earth didn't come from our sun. It came from past supernovae.
Of course looking at radio waves is a possibility.
Well said. It's pretty screwed up.
Please show me a fusor that can get trillions of neutrons per second. That's 5 orders of magnitude better than the best amateur effort, and 4 better than the professionals.
Microwaves do not cause biological damage unless you have hundreds of watts of them, and that's just heat.
It's really not physically possible. The frequency is too low to cause any ionising effects, leaving the only possible effect as heating, and I think that you get much more heating from say the hard drive in your laptop than you do from the 1W WiFi.
Is "not for retail" legally binding at -all-? What about the "Multipack - do not sell separately"? IANAL but I don't see why the companies have any right to dictate that.
Just nuclear physics :) Seriously though, that CANDU reactor looks like a pretty good design.
Some chemist correct me here, but I don't think there's any potential energy in just the hydrocarbons. You need oxygen to burn them in as well, which Titan doesn't have. I can't think of a way to extract energy from them alone.
Basically, the radiation and lack of sunlight (Titan is very cold) pretty much rule out the possibility of life. Spectra from Earth-based telescopes show no signs of oxygen in the atmosphere - this isn't required for basic life but I think the consensus is that anything advanced enough to have developed intelligence needs a lot of energy and that has to come from respiration with oxygen. People talk about other forms of life based on silicon etc, but I'm pretty sure that no serious scientists think that's a possibility. ET life may not be 'as we know it' but we should know it when we see it, and we aren't seeing it on Titan.
You'd use a Farnsworth fusor as a neutron source? I don't think they produce enough neutrons for significant activation. It is possible to build a fission reactor from natural U metal but I don't think it's easy at all!
This is pretty laughable. Ad homoneim it may be, but Richard Hoagland is pretty much the worst offender in pseudoscience.
Ah, true.
What? Far Cry has a dynamic plotline? All I saw was a cheesy James Bond rip-off.
I. Hate. That. Fucking. Song.
Distance really matters very little in spaceflight. Delta-V is what counts, and the amount needed to reach Venus from the Earth's surface isn't a lot different (within 20%) to that needed to reach Mars, or the Moon, because the vast majority is used up in getting to Earth orbit. It would take less time to reach Venus than Mars but you pretty much have to spend several months on-planet anyway to wait for them to be in the right orbital positions again for the return journey... and an extra 3 months in a spacecraft is no big deal technologically.
Furthermore you'd need a lot more rocket fuel for the ascent from Venus due to its substantially heavier gravity than Mars. All this is beside the point because designing something to survive Venus surface temperature for more than a few hours is just about impossible - you somehow have to build a refrigerator that can get its hot/radiative side to at least 700C and have the whole not lot melt. The pressure isn't so much of a challenge but the astronauts wouldn't be able to venture outside in anything short of a submarine, and what's the point in doing that?
Okay.. I suck. (not enough coffee?)
(Please correct me if I'm wrong about this, IANAA yet)
No, this is comparing apples and oranges.