Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: acsinuk on 06/11/2018 14:44:42
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If the stars and our sun is made of anti-matter then its corona will contain anti-matter plasma. So how long will it be before the probe is totally annihilated?
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The Sun is almost entirely composed of matter (there may be some positrons due to beta decay events, but those would quickly annihilate with the electrons in the Sun). The Genesis spacecraft collected samples of the solar wind and brought them back to Earth in 2004. The solar wind samples were found to contain matter, not antimatter.
If you're speaking in purely hypothetical terms, then the time required for the probe to annihilate will depend very much on its distance from the Sun.
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You don't need to travel to the Sun to sample the Sun's atmosphere - the Solar Wind carries parts of the Sun's atmosphere all the way to the Earth (and beyond). If the Sun were made of antimatter, it would affect astronauts in Earth orbit.
See: https://en.wikipedia.org/wiki/Solar_wind
In fact, scientists believe that our local cluster of galaxies (and beyond) is almost entirely made of matter, although as Kryptid says, the occasional antimatter particle can be produced in nuclear events, or energetic interactions like cosmic rays, supernovas and black holes.
If there were significant amounts of antimatter, space telescopes would detect characteristic gamma rays from their annihilation with normal matter.
Why "our universe is almost totally matter with almost no antimatter" is one of the unsolved problems in Physics.
See: https://en.wikipedia.org/wiki/Antimatter
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An interesting question would be, if the sun were made of antimatter, how long would the Earth last?
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It is inconceivable that the Earth and the Sun could be formed of different forms of matter as the have both formed from the same gas cloud.
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It is inconceivable that the Earth and the Sun could be formed of different forms of matter as the have both formed from the same gas cloud.
I think the thread lost any hope of scientific plausibility some time ago, but essentially we made the same point.
Because the Earth is matter, the Sun is not antimatter.
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NASA have already lost touch with Parker signals but I take it they can track its position with telescopes and will see if it is suddenly annihilated? December seems to be forever to wait.
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NASA have already lost touch with Parker signals but I take it they can track its position with telescopes and will see if it is suddenly annihilated? December seems to be forever to wait.
Why would it be suddenly annihilated?
Boiled, yes, sure; but not annihilated
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Well, thank goodness NASA have managed to get a signal from Parker which means it is still with us. The feedback from its close encounter with the sun will I am sure be truly useful in connection with any variations in the solar wind H+ions and electron velocities and the effect the suns magnetic field is having inside the corona.
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NASA have already lost touch with Parker signals
The Parker Solar probe is in a very elliptical orbit around the Sun.
This means that on every orbit, it passes behind the Sun (from the viewpoint of Earth), and loses contact with Earth, since radio waves can't pass through the conductive plasma of the Sun. That means that it needs to be very autonomous.
On every orbit, it also passes close to the Sun or even in front of the Sun (from Earth's viewpoint). Communication is lost at these times because the Sun's blackbody radiation is incredibly intense at radio frequencies, and the small radio transmitter and small dish can't produce enough signal to overcome the Sun's intense interference. The probe must move some distance away from the Sun's visible disk before communication is once again possible with Earth.
In a high-noise environment (close to the visible disk of the Sun), the probe will transmit a very simple signal (they mention 4 distinct states) which transmits a very well-defined pattern which can be detected by radiotelescopes on Earth. Once it moves further from the Sun's disk, they will change over to more complex transmission codes which can uplink the "quick look" summary to Earth, so that scientists can then argue about which parts to download the details, and in which sequence...
track its position with telescopes
These would be radiotelescopes. The Parker probe would be impossible to see in the glare of the Sun's light using optical telescopes as it is too small, too dark, and too close to the Sun, and the sky is too bright in the daytime.
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Thanks Evan, Is there any sign of a signal yet as I think 4 December was mentioned as date of expected reconnection??
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Thanks Evan, Is there any sign of a signal yet as I think 4 December was mentioned as date of expected reconnection??
Perihelion took place on on Nov 5, and the probe passed it first post perihelion health test on Nov 16.
It is presently heading away from the Sun before looping back for the next perihelion pass in April
Here is a link showing where the probe is at this time:
http://parkersolarprobe.jhuapl.edu/The-Mission/index.php#Where-Is-PSP
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Thanks Janus, I found an article on space.com that showed a video clip taken from parker probe which shows the suns emission pattern with mercury passing by in the background. The emissions pattern shows that the sun is like a huge lighthouse beaming particles and light outwards but not at all equal in all directions. Could it be that the major beams are directed towards the heaviest planets which are linked to the sun magnetically in sort of magnoflux tunnels do you think?
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Could it be that the major beams are directed towards the heaviest planets
The solar wind is mostly one direction - away from the Sun. To do this it must overcome the Sun's enormous surface gravity, which has far greater impact than the tiny tugs of Jupiter, Saturn or Earth (which is much closer than Jupiter). So I suggest that the location of planets has no impact on the direction of the solar wind leaving the Sun.
The solar wind can be rather gusty - especially when a Coronal Mass Ejection event happens, blasting a billion tons of Sunstuff into space. CMEs are driven by reconnection of powerful magnetic fields around sunspots, which are again far more powerful than tiny gravitational tugs from planets.
The CME does create a disturbance of Earth's magnetic field when it strikes Earth, but I have not seen evidence that CMEs are preferentially directed towards Earth, or any other planet. The frequency, severity and direction of CMEs seems to be driven primarily by the quantity and location of sunspots, which follow a roughly 11/22 year pattern.
See: https://en.wikipedia.org/wiki/Coronal_mass_ejection