CAPSLOCKSTUCK
Spaced Out Lunar Tick
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| System Name | Party On |
|---|---|
| Processor | Xeon w 3520 |
| Motherboard | DFI Lanparty |
| Cooling | Big tower thing |
| Memory | 6 gb Ballistix Tracer |
| Video Card(s) | HD 7970 |
| Case | a plank of wood |
| Audio Device(s) | seperate amp and 6 big speakers |
| Power Supply | Corsair |
| Mouse | cheap |
| Keyboard | under going restoration |
A pair of failed satellites that was knocked into an oddly-shaped orbit could still prove useful by helping to confirm a 100-year-old theory of physicist Albert Einstein.
The European Space Agency (Esa) has announced its ill-fated GPS satellites Galileo 5 and Galileo 6 will be used to verify if time passes more slowly the closer an object gets to a gravitational field.
The year-long test is expected to greatly improve results from previous studies of the phenomenon. The satellites have highly accurate atomic clocks on board necessary to ensure a good GPS signal, but their current orbits means they cannot be used for navigation purposes.
Instead these precise clocks could allow scientists to measure the effects of gravity on time. Under Einstein's General Theory of Relativity, gravity can warp the fabric of space time.
The experiment is a serendipitous silver lining to the Galileo launch fiasco of August 2014.
The two satellites were supposed to finally give Europe its own GPS network, freeing it from dependency on a network of American satellites that currently provide the service.
Launched in a Russian Soyuz rocket from French Guyana, the mission appeared to initially go smoothly. However, a faulty upper stage threw both Galileo satellites off-kilter, making them useless for navigation purposes.
Following the failure, Esa experts managed to slightly tweak the orbit of the two Galileo satellites in order to make them more circular. Even so, the satellites are moving along a stable but very elongated course, soaring and falling by some 5,300 miles (8,500 km) every day.
The Galileos' continual shifts seem like a quick way to verify one of the main assumptions of Albert Einstein's General Theory of Relativity.
In the famous work, published 100 years ago this month, the German physicist predicted that time flows more slowly the closer one is to a massive object exerting its attraction.
This has already been tested in 1976, when Gravity Probe A - a spacecraft equipped with an hyper-accurate atomic clock - was shot 6,200 miles (10,000 km) into space, to fall back on Earth after two hours.
The data from the probe revealed that, in effect, the clock on board had sped up during its trip.
The results from that early experiment are currently used by navigation satellite, which while giving directions have to take into account that time run faster up there.
Even a mistake of some tenths of microsecond per day can produce a navigation error of around six miles (10km).
However, new information from the wandering Galileo satellites - which are both carrying hydrogen atomic clocks and are constantly in touch with receiving stations on Earth - will be crucial to improve our knowledge of how time flows at different gravity levels.
'Now, for the first time since Gravity Probe A, we have the opportunity to improve the precision and confirm Einstein's theory to a higher degree,' Esa satnav expert Javier Ventura-Traveset explained in an online statement.
'This opens up the prospect of gradually refining our measurements by identifying and removing systematic errors. Eliminating those errors is actually one of the big challenges,' he added.
Esa estimates the results will be four times more accurate than those collected in 1976 due to the long duration of the mission.
The Galileo satellites will be carrying out their test for twelve months, compared to Gravity Probe A's two hours.
The two teams devising the experiments are Germany's ZARM Center of Applied Space Technology and Microgravity, and France's SYRTE Systèmes de Référence Temps-Espace, both specialists in fundamental physics research.
https://www.zarm.uni-bremen.de/
https://syrte.obspm.fr/spip/?lang=fr
THEORY OF GENERAL RELATIVITY: NEWTON VS EINSTEIN
Sir Isaac Newton is credited for discovering gravity in his three laws of motion.
The laws assume that the force between two objects depends on the mass and distance of each and, using these concepts, it is possible to calculate the orbits of planets precisely.
However, Mercury's orbit was found to be an exception to this rule.
On 25th November 1915, Albert Einstein put forward his Theory of General Relativity.
It was able to reproduce Newton's notions of gravity and all its predictions of motion, but also fixed many of the discrepancies, including Mercury's orbit.
The orbit is not quite circular which means that there is a point at which it is closest to the sun.
Newton's theory predicts that this point is fixed, but observation shows it slowly rotates around the sun - and Einstein found that general relativity correctly described this rotation.
Einstein proposed that gravity is caused by matter bending space and time, and that the two are intrinsically linked as 'spacetime'.
'In other words, spacetime is not a stage on which matter are actors, but that matter itself can warp spacetime by moving within it,' said Dr Toby Wiseman, a member of Imperial College's theoretical physics group.
According to Newton, the sun affects the orbit of Earth because of its larger mass, suggesting the Earth is not moving freely.
Einstein instead proposed Earth is moving freely, along the analogue of a straight line, but through a curved spacetime that has been distorted by the mass of sun.
Einstein had previously shown that the speed of light is always the same for everyone, and that space and time are experienced differently by different people.
He continued that if space comes in three dimensions - length, breadth and depth - then time is the fourth dimension.
Together they form the framework of space-time, a revelation that formed Einstein's theory of special relativity, posted 10 years earlier in 1905.
The discovery of a constant speed of light also meant that Newton's laws of gravity violated the universal speed limit.
If attraction between the sun and the Earth was what caused gravity, then a shift in the position of the sun would cause an instantaneous shift in the orbit of the Earth.
But this shift would be faster than the speed of light - contradicting the findings of Einstein's special relativity.
'There's a certain rightness to the theory - it's so logically complete, with so few assumptions,' added Imperial College theoretical physicist Professor Fay Dowker.
'It just seems so right. All the predictions it makes have been confirmed wherever they've been tested.'
Source: Imperial College London
The European Space Agency (Esa) has announced its ill-fated GPS satellites Galileo 5 and Galileo 6 will be used to verify if time passes more slowly the closer an object gets to a gravitational field.
The year-long test is expected to greatly improve results from previous studies of the phenomenon. The satellites have highly accurate atomic clocks on board necessary to ensure a good GPS signal, but their current orbits means they cannot be used for navigation purposes.
Instead these precise clocks could allow scientists to measure the effects of gravity on time. Under Einstein's General Theory of Relativity, gravity can warp the fabric of space time.
The experiment is a serendipitous silver lining to the Galileo launch fiasco of August 2014.
The two satellites were supposed to finally give Europe its own GPS network, freeing it from dependency on a network of American satellites that currently provide the service.
Launched in a Russian Soyuz rocket from French Guyana, the mission appeared to initially go smoothly. However, a faulty upper stage threw both Galileo satellites off-kilter, making them useless for navigation purposes.
Following the failure, Esa experts managed to slightly tweak the orbit of the two Galileo satellites in order to make them more circular. Even so, the satellites are moving along a stable but very elongated course, soaring and falling by some 5,300 miles (8,500 km) every day.
The Galileos' continual shifts seem like a quick way to verify one of the main assumptions of Albert Einstein's General Theory of Relativity.
In the famous work, published 100 years ago this month, the German physicist predicted that time flows more slowly the closer one is to a massive object exerting its attraction.
This has already been tested in 1976, when Gravity Probe A - a spacecraft equipped with an hyper-accurate atomic clock - was shot 6,200 miles (10,000 km) into space, to fall back on Earth after two hours.
The data from the probe revealed that, in effect, the clock on board had sped up during its trip.
The results from that early experiment are currently used by navigation satellite, which while giving directions have to take into account that time run faster up there.
Even a mistake of some tenths of microsecond per day can produce a navigation error of around six miles (10km).
However, new information from the wandering Galileo satellites - which are both carrying hydrogen atomic clocks and are constantly in touch with receiving stations on Earth - will be crucial to improve our knowledge of how time flows at different gravity levels.
'Now, for the first time since Gravity Probe A, we have the opportunity to improve the precision and confirm Einstein's theory to a higher degree,' Esa satnav expert Javier Ventura-Traveset explained in an online statement.
'This opens up the prospect of gradually refining our measurements by identifying and removing systematic errors. Eliminating those errors is actually one of the big challenges,' he added.
Esa estimates the results will be four times more accurate than those collected in 1976 due to the long duration of the mission.
The Galileo satellites will be carrying out their test for twelve months, compared to Gravity Probe A's two hours.
The two teams devising the experiments are Germany's ZARM Center of Applied Space Technology and Microgravity, and France's SYRTE Systèmes de Référence Temps-Espace, both specialists in fundamental physics research.
https://www.zarm.uni-bremen.de/
https://syrte.obspm.fr/spip/?lang=fr
THEORY OF GENERAL RELATIVITY: NEWTON VS EINSTEIN
Sir Isaac Newton is credited for discovering gravity in his three laws of motion.
The laws assume that the force between two objects depends on the mass and distance of each and, using these concepts, it is possible to calculate the orbits of planets precisely.
However, Mercury's orbit was found to be an exception to this rule.
On 25th November 1915, Albert Einstein put forward his Theory of General Relativity.
It was able to reproduce Newton's notions of gravity and all its predictions of motion, but also fixed many of the discrepancies, including Mercury's orbit.
The orbit is not quite circular which means that there is a point at which it is closest to the sun.
Newton's theory predicts that this point is fixed, but observation shows it slowly rotates around the sun - and Einstein found that general relativity correctly described this rotation.
Einstein proposed that gravity is caused by matter bending space and time, and that the two are intrinsically linked as 'spacetime'.
'In other words, spacetime is not a stage on which matter are actors, but that matter itself can warp spacetime by moving within it,' said Dr Toby Wiseman, a member of Imperial College's theoretical physics group.
According to Newton, the sun affects the orbit of Earth because of its larger mass, suggesting the Earth is not moving freely.
Einstein instead proposed Earth is moving freely, along the analogue of a straight line, but through a curved spacetime that has been distorted by the mass of sun.
Einstein had previously shown that the speed of light is always the same for everyone, and that space and time are experienced differently by different people.
He continued that if space comes in three dimensions - length, breadth and depth - then time is the fourth dimension.
Together they form the framework of space-time, a revelation that formed Einstein's theory of special relativity, posted 10 years earlier in 1905.
The discovery of a constant speed of light also meant that Newton's laws of gravity violated the universal speed limit.
If attraction between the sun and the Earth was what caused gravity, then a shift in the position of the sun would cause an instantaneous shift in the orbit of the Earth.
But this shift would be faster than the speed of light - contradicting the findings of Einstein's special relativity.
'There's a certain rightness to the theory - it's so logically complete, with so few assumptions,' added Imperial College theoretical physicist Professor Fay Dowker.
'It just seems so right. All the predictions it makes have been confirmed wherever they've been tested.'
Source: Imperial College London
