If this will ever get funded (they recently got some money to make first studies) it will be a telescope the size of half the Netherlands. This is of course not a filled aperture, but a sparse one operating at very low frequencies (10-250 MHz, on both sides of the FM frequencies). It will consist of some hundred small "antenna parks" spread around the country and uses a lot of computer power to generate images. It could be a precursor for SKA.
I had discussions with some devoted christians and got kind of annoyed by the fact that they try to use pseudo-scientific arguments in a scientific debate. (They never found the missing link etc.). I think there are only two possiblities and nothing in between:
1) You believe in evolution and all the scientific evidence.
2) You believe that some god put all the fossils in the ground just to fool us.
Disclaimer: i am a fanatical atheist and believe in 1).
Does anybody know if firewire is being used to replace the old and slow GP-IB in the measurement instrument business? (oscilloscopes, frequency generators and all the other lab stuff)
I'm getting a bit tired of programming a brand new instrument with a 20 year old protocol. I think Firewire would be ideal for that (better than USB).
As posted by many others i think this is not a big issue and most western countries already have their own sort of social security number. I agree that their might be serious privacy problems if the system is used in to many places (e.g. if your boss could track via your ID what you bought last night in the supermarket).
A recent survey in the Netherlands however showed some cases where is not used enough. A simple coupling of some databases showed that some ID's were used by up to 100 illegal workers and that some ID holders were being treated in three hospitals simultaneously.
They did something similar some years ago with the mars pathfinder mission. By combining all the images from the stereo-imager and the rover they were able to glue everything together into a textured 3d model.
Its not just cancelling of the gravitational forces of the two bodies. All the action takes place into a rotational reference frame, so you have to factor in some subtle forces like the Coriolis Force.
If you do all the math it turns out there are 5 stable Lagrange points, two of which even allow a stable orbit around it.
As far as i know this is complete BS. Globally combining telescopes with just accurate clocks and a lot of computing power only works for radio telescopes. They measure frequencies in the GHz regime, which means you can measure the phase of your signal with respect to an atom clock. Correlating the recorded signals from the various telescopes can then be done by computer.
Combining telescopes in the optical domain (frequency ~10^14 Hz) is only possible by correlating in the optical domain with an interferometer. This means you need optical delay-lines (VLTI) of maximum some hundred meters or fibers (OHANA) of maximum a few kilometers.
First of all the space station is not the place where you want your extremely sensitive telescopes. I guess that the pointing of the telescope would be lost if an astronaut did so much as breathing.
Second, there is now and in the foreseable future no way to launch a telescope the size of a football-field into orbit. Think about the costs: Hubble, with a primary mirror of only 2 meters, costed several billions for the launch and all the maintance flights. The OWL would cost the same order of magnitude and would give you a diameter of 100 meter!
It is true that some wavelengths (x-ray, UV, far IR) can only be viewed in space, but the visible and near IR can convienently be viewed from earth. (If you have the adaptive optics working.)
This technique is based on photonic bandgap fibers. They were invented by Phillip Russell at Bath University (UK).
These fibers contains a pattern of hollow channels that form the 2D equivalent of a multilayer mirror. Light can not travel in such a region. One channel in the middle of the matrix is missing, creating a defect state where the light can travel.
Slashdot Mirror
If this will ever get funded (they recently got some money to make first studies) it will be a telescope the size of half the Netherlands. This is of course not a filled aperture, but a sparse one operating at very low frequencies (10-250 MHz, on both sides of the FM frequencies). It will consist of some hundred small "antenna parks" spread around the country and uses a lot of computer power to generate images. It could be a precursor for SKA.
I had discussions with some devoted christians and got kind of annoyed by the fact that they try to use pseudo-scientific arguments in a scientific debate. (They never found the missing link etc.). I think there are only two possiblities and nothing in between:
1) You believe in evolution and all the scientific evidence.
2) You believe that some god put all the fossils in the ground just to fool us.
Disclaimer: i am a fanatical atheist and believe in 1).
After reading the story and closing the window, the exit pop-up invites me to take a bet at some online casino...
I'm getting a bit tired of programming a brand new instrument with a 20 year old protocol. I think Firewire would be ideal for that (better than USB).
To get an idea of the possible data rate with this machine: it took him 22 hours!
A recent survey in the Netherlands however showed some cases where is not used enough. A simple coupling of some databases showed that some ID's were used by up to 100 illegal workers and that some ID holders were being treated in three hospitals simultaneously.
They did something similar some years ago with the mars pathfinder mission. By combining all the images from the stereo-imager and the rover they were able to glue everything together into a textured 3d model.
If you do all the math it turns out there are 5 stable Lagrange points, two of which even allow a stable orbit around it.
Anyone else noticed this?
Combining telescopes in the optical domain (frequency ~10^14 Hz) is only possible by correlating in the optical domain with an interferometer. This means you need optical delay-lines (VLTI) of maximum some hundred meters or fibers (OHANA) of maximum a few kilometers.
Second, there is now and in the foreseable future no way to launch a telescope the size of a football-field into orbit. Think about the costs: Hubble, with a primary mirror of only 2 meters, costed several billions for the launch and all the maintance flights. The OWL would cost the same order of magnitude and would give you a diameter of 100 meter!
It is true that some wavelengths (x-ray, UV, far IR) can only be viewed in space, but the visible and near IR can convienently be viewed from earth. (If you have the adaptive optics working.)
Just my 2 eurocents.
Area of moons orbit: pi*(384.4e6)^2 [m^2]
Projected area of earth: pi*(6.378e6)^2 [m^2]
Chance of being hit if asteroid passes within moons orbit: P=(6.378/384.4)^2 = 0.02%
This technique is based on photonic bandgap fibers. They were invented by Phillip Russell at Bath University (UK). These fibers contains a pattern of hollow channels that form the 2D equivalent of a multilayer mirror. Light can not travel in such a region. One channel in the middle of the matrix is missing, creating a defect state where the light can travel.