Реферат на тему Sunspots Essay Research Paper Our Sun continuously
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Sunspots Essay, Research Paper
Our Sun continuously converts hydrogen into helium and with this process it
provides the essentials for life processes. In doing this it controls “our climate,
provides light, raises tides, and drives the food chain” (Schaefer 34). Our Sun
also has influenced many beliefs now and in the past. History has documented
Sun worshipping religions while many current societies use solar calendars
(Schaefer 34).
Because the Sun is so influential, imperfections of the Sun, such as
sunspots will continue to impact life on Earth. The discovery of sunspots is
correlated with the invention of the telescope in 1608, although there are earlier
recordings of sunspot like activity from China (Schaefer 35). Galileo was one of
the astronomers who decided to publish his findings and use sunspots in one of
his theories of Chief World Systems (Schaefer 35-6).
Today many patterns including real estate sales to fluctuations in the
climate have been attributed to the cycle of sunspots. These fluctuations may be
an explanation of the decline of Sun worship in India due the increased sunspot
activity during the time of the Medieval Maximum. Throughtout history these
fluctuations have been omens (e.g. a slave revolutionists incited a riot when he
interpreted the site of a large black area on the Sun as the black taking over the
white) (Schaefer 38). There are also modern examples of solar fluctuations
affecting the Earth like the delayed launch of the Hubble Telescope (Schaefer
38) and the disruptions in electrical and radio technology during solar flares due
to increased activity of sunspots at the last solar maximum in 1989.
Sunspots are the most apparent features on the Sun’s surface or
photosphere. Anyone could use a filter such as a welder’s helmet to observe
groups of sunspots. A sunspot consists of two regions, the umbra and the
penumbra. The temperature of the umbra can be as low as 4,000 K and the
penumbra that surrounds the umbra has a temperature of about 5,500 K which
contrasts to the photospheric temperature of 6,000 K. The difference in
temperatures makes the sunspots appear dark against the brightness of the
photosphere (Nicolson 123).
A sunspot’s average size is comparable with the Earth. They form in
regions of concentrated magnetic fields. These fields hamper the flow of energy
to the affected area. The magnetic fields on the Sun are detected by the
Zeeman effect, which shows a single spectral line that splits if a magnetic field is
present (Nicolson 124). In each sunspot pair in the northern hemisphere the first
spot has a north magnetic polarity and the second has a south magnetic polarity
{figure 1}, while in the southern hemisphere it is the opposite pattern. In sunspot
groups the polarity of the sunspots gets increasingly complex (Nicolson 124).
The sunspots follow a cycle of eleven years. The number of sunspots
varies monthly from zero to the hundreds. During the eleven year cycle there are
periods called solar maximum and solar minimum where the number of sunspots
reaches its peak or low. At the time of solar max the Sun’s magnetic poles
reverse. The north magnetic pole switches to extend through the southern
hemisphere and the south magnetic pole extends through the northern
hemisphere. In fact the Sun reached its solar max in February of this year
(Philips 1).
According to astrophysicist, K. V. K. Nehru the magnetic poles reverse
because of a theory of high range temperature matter. His theory states that
one way high temperature matter acts in is thredules, which is “[m]atter in the
ultra high temperature range manifests as slender, unidirectional, expanding
threads that keep forming and dissolving” (1Nehru 8). Nehru states that
co-magnetic lines follow the thredules as they expand. North and south
thredules form two “sheaves” one north polarized and one south polarized, but
where the sheaves interact opposite polarities are adjacent to each other {figure
2}. The thredules cannot expand beyond the high temperature core, however
the magnetic fields lengthen out into space. When the magnetic lines reach into
space the opposite polarity extending out from the opposite side attract each
other and form loops. Over time this attraction leads to the angle of where the
magnetic field extends from is altered from the high latitudes to lower latitudes
until the polarities flip (2Nehru 1-3).
This theory explains how the magnetic poles of the Sun reverse
and it also answers another question about the nature of sunspots. When the
sun begins it cycle of sunspots the majority of the sunspots are at the higher
latitudes while later in the cycle they appear at the lower latitudes. This
resembles the pattern of where the magnetic fields extending from the thredules
are positioned.
The National Center of Atmospheric Research is using sunspots to try to
predict the damage the Sun radiation is causing to the Earth’s atmosphere. To
do this they measure the amounts of radiation fluctuations. Utilizing that
information they can estimate the amount of radiation that reaches Earth. Their
results will assist astronomers and other scientist in understanding radiation’s
effect on the atmosphere (Analyzing 11-12).
Another project called Ulysses is currently being used to study the Sun.
The probe Ulysses was “launched in 1990 to observe the solar system from very
high solar latitudes” (Philips 2). Ulysses is the first probe to ever observe from
such latitudes. Ulysses has just finished flying under the Sun’s south pole and in
the fall it will be flying of the north pole at a solar latitude of 2.2 AUs (Philips 2).
This project will hopefully enable scientists to learn more about sunspots and
other properties of the Sun.
Understanding more about sunspots, their cycle, radiation, and magnetic
properties will facilitate scientists to unlock the mysterious workings of the Sun.
With today’s technology this understanding will come more quickly. Knowledge
of sunspots may lead us to be able to predict when solar activity could affect the
Earth like it did during the solar max in 1989. Information like this could
eventually allow us to be able to protect ourselves from solar radiation.
“Analyzing Variation in the Sun’s Radiation”. USA Today. 26 2637 (1998) :
11-12.
Nehru, K.V.K. Glimpses Into the Structure of the Sun—Part 1 The Nature of
Stellar Matter. March 22, 2001. .
Nehru, K.V.K. Glimpses Into the Structure of the Sun—Part 2 The Solar Interior
and the Sunspot. March 22, 2001.
Nicolson, Iain. Unfolding Our Universe. New York: Cambridge University Press,
1999. 123-4; 276+
Philips, Tony Dr. “The Sun Does a Flip.” SpaceScience. Feb. 15, 2001. March
19, 2001. .
Schaefer, Bradley E. “Sunspots that changed the World.” Sky & Telescope. 93.4
(1997). 34-38.