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iantresman
2004-Aug-01, 10:36 PM
Scientists Explain Mysterious Plasma Jets On The Sun (http://www.lmsal.com/Press/spicules2004/)

According to the press release above, spicules (or chromospheric jets) move towards us at ~30,000 miles/hour (~13.5km/s). But the escape velocity of our Sun is 1,381,600.8 mph (618 km/sec). Since 30,000mph is only 2% of the Sun's escape velocity:

a. Should the particles fall back to the Sun?
b. Is gravity not the only force at work?

Regards,
Ian Tresman

milli360
2004-Aug-02, 01:14 AM
c. Wait until you get to figure three! :)

Ricimer
2004-Aug-02, 01:22 AM
yeah, look at figure 3.

The materail falls back after a bit.

electromagneticpulse
2004-Aug-02, 01:26 AM
where does the spicules mover towards us at 30000 mph?

One explenation is that it reaches 30000 mph after, so its inital speed is 1,4101,600.8 mph the energy that it uses to escape the gravity leaves it traveling at 30000 mph and theres your speed.

Also it flows along a magnetic field and often its just the tail end that is ejected, it acts like a trebuchet the whole thing moves but only a small amount is released. Also it would be heavyer plasma's that where released by my guess so more helium so the sun wouldnt end up going out so quickly.

2004-Aug-03, 06:07 AM
Is there any man-made spacecraft that can exceed the Sun's escape velocity? 618 km/s seems like a very high speed.

scourge
2004-Aug-03, 06:42 AM
Is there any man-made spacecraft that can exceed the Sun's escape velocity? 618 km/s seems like a very high speed.

I doubt we have anything to come close to that speed...for comparison, Voyager 2's average velocity between Uranus and Neptune was 19 km/s, 42,000 mph. The space shuttle orbits at around 18,000 mph.

Zamzara
2004-Aug-03, 05:43 PM
Is there any man-made spacecraft that can exceed the Sun's escape velocity? 618 km/s seems like a very high speed.

It isn't necessary to reach that speed: that is the escape velocity for an object at the surface of the sun. Out at the distance of the Earth the escape velocity is about 42km/s, and at Jupiter it is more like 19 km/s.