
NASA Discovers A Ring Around The Solar System - epi0Bauqu
http://www.npr.org/templates/story/story.php?storyId=113914677&ft=1&f=100
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jaydub
Why do the images from IBEX take 6 months to be composed?

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electromagnetic
AFAIK the IBEX isn't a photographic telescope, it develops its images through
energetic neutral atoms and not photons. It takes over 10 hours for light to
get from the sun to the heliosphere, so to retrieve particles that are
travelling at sub-light velocities and are moving _into_ the solar wind must
take considerable time alone, and then it requires building an image from the
particle densities retrieved.

Simply put, unless you ask a NASA scientist exactly how and why, the answer is
and likely always will be; it just does.

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Tamerlin
You don't retrieve those particles; an admittedly absurd extension of your
reasoning would imply that it takes 200 million years to image a quasar,
because that's how long it takes to retrieve the photons that form your image.

What we're seeing here is both faint and enormous. Both characteristics make
it hard to detect, and it isn't bright enough to capture without a long
exposure, plus you can't look at it during the day, and you can't see the side
beyond the sun... all characteristics that lead to longer imaging times.

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JoeAltmaier
Low-level signal = long exposure time

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roundsquare
Doesn't this make anyone else wonder about the accuracy of statements
physisicts make about other galaxies? I mean, it seems to me like if we're
still disocvering things like this about our solar system (relatively nearby)
then how in the world can anyone be confident about statements made about
other galaxies (compratively further off)?

To some degree, I'm sure its just the fact that articles written for non-
scientests tend to make them sound more sure than they are, but it still seems
strange to me...

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bdr
Not really. They hadn't put this data together before. Now they did, and they
found the ring. The conclusions about other galaxies are also based on data.
It's not like anyone had previously said that there is no such ring around the
solar system, the data just wasn't there.

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roundsquare
Sure, but I guess my point is that we had only indirect data about the fringe
of our solar system before, and now that we have more direct data (i.e.
actually sending a satellite out there) we discover something pretty big. The
data we have about further away galaxies is even more indirect and the light
we get from them is subject to any number of possible phenomena we may not
have accounted for. The level of confidence about the conclusions we draw
though seems way to high given that its clear there are phenomena we don't
know about.

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ANH
Causes a human to wonder how these protective stellar bubbles' interactions
with the galactic environment affect the development of (possible) life in
star systems.

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matt-kantor
Remnants of our solar accretion disk?

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tierack
The stripe is perpendicular to the direction of the magnetic field of the
galaxy and not in line with the ecliptic plane. The interview I heard here
([http://ww.npr.org/templates/transcript/transcript.php?storyI...](http://ww.npr.org/templates/transcript/transcript.php?storyId=113914677))
suggests that the hydrogen that makes up the stripe is being continuously
accumulated, not leftover from old times.

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electromagnetic
If it's perpendicular to the solar systems trajectory, then it could
potentially be an aerodynamics issue not taken into account.

AFAIK the solar system is moving at essentially supersonic speeds through the
solar medium, which causes the bowshock, so couldn't this just be an eddy
current we've been unable to distinguish either because it's not present in
smaller scales, or simply because it's normally small enough to be a
statistical anomaly?

The physics of our solar systems action are essentially similar to small body
physics, the problem is that they're blown up on scale unimaginable to us.
Essentially our comparison of physics is akin to comparing getting up to turn
the tv on with a trip to Alpha Centauri and back.

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assemble
Ummmmm... There is almost no air in space, which causes there to be no sound
in space. Therefore, the ability to go 'supersonic' in space is highly
overrated, seeing as sound simply doesn't even try. This all leads me to
believe there's probably not bowshock either.

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novas0x2a
You're right that there isn't much air in space, but bowshock isn't specific
to "air". There most definitely is bowshock in space:
<http://en.wikipedia.org/wiki/Bow_shock>

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assemble
The person mentioned supersonic, so I figured that's what the bow wave was
referring to. Doesn't help that I work in aircraft and haven't been keeping up
on my space knowledge lately ;) (And I don't work on cool military supersonic
things, so my supersonic is rusty too...)

I still maintain you can't do do supersonic things in space. The would imply
sound moves in space.

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GavinB
In other news, women now find the solar system 10% more attractive.

