22-year solar cycle?

Question

What is a 22-year solar cycle?

a.It refers to a periodic variation in the number of sunspots, their latitudes, and their magnetic polarities.

b.It is the time it takes the Sun to complete one revolution about the center of mass of the Solar System.

c.It refers to a periodic variation in the size, luminosity, and temperature of the Sun.

d.Every about 22 years, the magnetic field of the Sun reverses.

e.It is the time for a typical plume of gas to rise from the bottom of the convection zone to the top of the convection zone, or the bottom of the photosphere, and then to sink back to the bottom of the convection zone.



Which of those above statements is true?? Thank You

If im not mistaken D is true, but could A be right also?

Your helps appreciated

Answer 1

This is a bit tricky.

We need to distinguish between things that happen in the Sun on an 11-year cycle and on a 22-year cycle, then ignore the 11-year stuff.

a. The polarity orderings of pairs of linked sunspots in either hemisphere (perhaps N - S in the north, S - N in the south) themselves reverse (in this case to S - N in the north, N - S in the south) every 11 years. So, while the "reversals" are a basic 11 year phenomenon, two such polarity reversals get you back to what you started with. So yes, in the end the whole thing is a periodic variation with a full period of 22 years, a "22-year solar cycle." (At the same time as the sunspots' polarity reversals, the overall magnetic field of the Sun reverses. We'll return to this in part d.)

b. Not true. The motion of the Sun about the Solar System's centre of mass is dominated by the effects of Jupiter and Saturn, with additional effects from the other planets. It produces a rather complex spiralling pattern that in no way looks anything like a "22-year cycle."

c. There are some changes of the order of 10^(-4) in the Sun's luminosity during the 11-year cycle, but it comes back to about its original value again after that amount of time. Has some even more subtle effect been noticed that now makes that a longer, 22-year cycle?

d. This statement, as it stands, is WRONG. The magnetic field of the Sun reverses EVERY 11 YEARS. However, a true statement is that after 22 years, the overall magnetic field REVERSES AGAIN. If, for example, the north magnetic pole of the Sun is "pointing up" for the first 11 years, it's "pointing down" for the second 11 years, after which it goes back to what it was at the start. So, the whole magnetic behaviour of the Sun's overall magnetic field is truly a 22-year cycle, but one that involves TWO (not just one) magnetic field reversals.

e. I don't think that there's any such simple connection. I believe that the basic reason for the actual length of these cycles has been a mystery for a long time. (But I'm ready to be educated on recent developments.)

Incidentally, it's been claimed that there is a 22-year cycle in wheat yields in the Mid-West, that might reflect how the overall 22-year solar magnetic cycle alters the solar wind and/or energetic particle inputs into Earth's atmosphere, thereby affecting the weather in a periodic way. Intriguing, if true.

I hope this helps.

Live long and prosper.

Answer 2

d. the different factors all coach an 11-twelve months cycle. observing the magnetic field although, we hit upon that successive 11-twelve months sessions have the photograph voltaic magnetic field in opposite guidelines, so counting that it doubles the cycle length.

Answer 3

I pick (D) because i think i read something about this yesterday...

EDIT: apperently (A) and (D) are both right because one happens every 11yrs and one happens ever 22yrs meaning that they both happinen in a time period that is the same... but since he said 22yrs in guessing your looking for (D)

Answer 4

see: http://en.wikipedia.org/wiki/Sun_spot_cycle

Basic sun spot cycle is 11 years