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Solar Flare Interference From 45k Lightyears Away
Wan2Be writes "Nasa has a story about a solar flare on Aug. 27 that affected our planet with radio bounces and blackouts - but it wasn't from old Sol, it was from SGR 1900+14, a neutron star about 45,000 light years away. "
Slight misconception from the summary. The event happened on August 27.
But that was August 27, 1998. Not just a couple weeks ago.
Time, as you know, is all relative.
As there is no absolute time... to say "it blew up but we didnt' see it yet" is actually inaccurate... it didn't blow up as far as we are concerned until we saw it. Before that, the effects of the explosion had no effect on the universe as far as we are concerned.
It's not jjust the light from the event, but the gravitational and other effects as well.. for all intents and purposes, the event doesn't happen until we see it.
Isn't it interesting that radio amateurs were one of the first groups noticed there was something strange going on?
It can't.
The fastest way for any information to travel (again, as far as we know) is as light. Period. So if the event that's happening is a propagating wavefront of light, nothing is going to get to us before the light itself. ("Light" here including other parts of the EM spectrum: radio, X-rays, whatever.)
Let's suppose that at the halfway point, ~22,500 LY away, the wavefront had some effect -- say, it hit a cloud of interstellar gas and caused that gas to fluoresce. Would we see that fluorescence? Maybe -- except while the light from that fluorescence is traveling toward us, so is the light from the original event. The light from the secondary events can't move any faster.
Okay, here's a terrestrial analogy. Let's suppose someone telephones me and says, "By the way, while I've got you on the line, I'm also calling Trigun on another phone." Now let's suppose I want to call you and warn you about this incoming call. (Maybe it's a bill collector.) No matter how quickly I try to call you, it doesn't matter, because the other guy has already placed the call. Does that make sense?
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
Not really. The interstellar medium has about 0.1 atoms per cm^3. This is about 1e20 times less then our atmosphere. 45000 light years is 4.2e22 cm, so it only had to go through the equivalent of 4.2 meters of our atmosphere.
So it's only the same amount of shit as it would encounter on a trip across your living room.
How well shielded? a few meters of water would sufice, but this is getting expensive to send into space.
That's a common misconception. In The Case for Mars, Dr Robert Zubrin uses NASA's own data to demonstrate that during a trip to Mars, astronauts would receive about as much radiation as someone who'd lived their life in Colorado. Yes, there is a slightly increased risk of cancer but a) you increase your own risk every time you fly and b) they're flying to Mars - and that's pretty damn risky in and of itself!