Space Mailbag: What's Up with the Sun?

Space.com ^ | November 5, 2003 | By Robert Roy Britt

[Aracelis]

Those verses have crossed my mind of late. Thank you!

[Doctor Stochastic]

Those things you find "hard to believe" and that are generally accepted may require some study to see why. Stellar evolution is rather well understood.

The total relative mass loss by the Sun from all reasons in only 9.13*10**(-14) per year.

[Aracelis]

That looks like a question a geologist would ask. I was thinking of it myself... Is that you?

Not this time, although the question has been on my mind.

[Physicist]

4.6e9 years x 4.2e9 kg/s mass lost = 6.1e26 kg loss

Very good. And how massive do you think the sun is?

I simply find it hard to believe that the Sun will be burnt out with 99.93% of its mass remaining.

Why? How much would you expect to remain?

[longshadow]

here's a thought, catalyzed in part by a comment back up the thread:

Has anyone investigated solar flare/CME activity coincident with reversal of the Earth's magnetic field as a mechanism for Mass Extinction in Earth's history?

If you were to have heavy solar activity during a period when the Earth's magnetic filed were changing polarity, I'd think there'd be a period of vulnerabilty during which the earth's surface would be bathed in x-rays from the flares and CME's.

Would there be an detectable remnant of such X-ray activity in the gelogic column, such that we could correlate such an event chronologically and compare it to instances of Mass Extinctions?

Or, be I all wet?

[Ff--150]

26. Men's hearts failing them for fear, and for looking after those things which are coming on the earth:

Today doctors assert one out of two Americans will have heart problems? Perhaps we do suspect changes on the way? :-)

[Aracelis]

I smell another research project. :^)

Off-the-cuff I'd say we may be able to correlate terrestrial fission tracks and the relative abundance of noble gases with paleomagnetic data, similar to work done on chondrites. Here are some interesting links:

Two-Stage Model of Protoplanetary Irradiation

Excess cosmogenic noble gases relative to chondritic matrix

Solar Gases in the Earth by Solar Wind Irradiation?

[myheroesareDeadandRegistered]

"The sun, the Sun? Well it's kinda like this my little darlings........

......It just keeps building pressure, building pressure, building pressure and building some more and more and more pressure till one day it just POPS like a big, fat pimple! It's really disgusting......."

[Aracelis]

I agree that massive changes are on the way. Simple reflection on the differences between American society from the time I was born and today, reveals much. I suspect today's fast-paced lifestyle has stripped from us our illusion of civility, and we are left with the most basic of human rights having to be publicly litigated and legislated.

[4CJ]

The total relative mass loss by the Sun from all reasons in only 9.13*10**(-14) per year.

If the Sun is to have 99.93% of it's original mass (hydrogen to helium) left after 10 billion years, wouldn't the rate per year be 7e-12?

[4CJ]

And how massive do you think the sun is?

1.99e30 kg.

How much would you expect to remain?

A lot less. Why do stars collapse? A .03% change in mass shouldn't cause it should it?

[Doctor Stochastic]

It isn't just the change in mass. As the hydrogen burns to helium, the star no longer produces enought energy to counteract its self-gravitation. Check with an astrophysics book or one of the better encyclopaedias (Britannica is good.)

[Physicist]

1.99e30 kg.

Very good. Now do you see why your reply #10 was wrong?

A lot less. Why do stars collapse? A .03% change in mass shouldn't cause it should it?

Why does a hot air balloon collapse, when you turn the burner off?

[ThinkPlease]

Why do stars collapse?

It's all about pressure balance. Pressure outwards is from radiative pressure, photons actually pushing on the matter, pressing inward is our old friend gravity. In nearly all stars, the pressure balance is enough to prevent collapse.

Most stars never collapse, the only ones that do are stars that go supernovae. As was said earlier, that only happens if the the star doesn't output enough energy to counteract the inward pressure of gravity. This occurs when the star runs into a fusion process that doesn't create energy, but actually takes energy to react. That process is the process of fusing two iron atoms together, and it only occurs at temperatures of several hundred million degrees celsius. This only happens in very high mass stars, like most O type stars.

[Barnacle]

IMPACT: A coronal mass ejection hurled into space by the superflare described below swept past Earth today (Nov. 6th) at approximately 1930 UT. Mild-to-moderate geomagnetic storms and high-latitude auroras are possible during the hours ahead.

http://www.spaceweather.com/

[Davea]

Thanks for the post PW and thanks for the ping Barnacle. Looks like the Sun is sleeping it off.....http://www.sec.noaa.gov/rt_plots/xray_5m.html

[StriperSniper]

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