[DOC] [TLE] Space Weather: Sunspots - Space.com [PAR] Feb 2, 2015 ... Space Weather: Though the sun is 93 million miles from Earth, its ... Studying the 
surface of the sun can reveal small, dark areas that vary in number and location. 
... According to NASA, sunspots are "the most visible advertisement of the ... The 
enormous sunspot of 2014 fired off several powerful solar flares. [DOC] [TLE] Sunspot - Wikipedia [PAR] Sunspots are temporary phenomena on the photosphere of the Sun that appear 
as dark spots compared to surrounding regions. They are areas of reduced 
surface temperature caused by concentrations of ... Their number varies 
according to the approximately 11-year solar cycle. Individual sunspots may 
endure anywhere... [DOC] [TLE] Layers of the Sun | NASA [PAR] It reaches from the surface visible at the center of the solar disk to about 250 
miles (400 ... The temperature in the photosphere varies between about 6500 K 
at the ... SDO takes images of the sun in many different wavelengths at a high 
time .... the coronathe outermost, wispy layer of the sun's atmosphere is 
hundreds of... [DOC] [TLE] Solar Storm and Space Weather - Frequently Asked Questions | NASA [PAR] Apr 26, 2016 ... Prominences are anchored to the Sun's surface in the photosphere, and extend 
... corona for several months, looping hundreds of thousands of miles into space. 
.... in the sunspot number (a measure of the number of dark spots and ... At solar 
minimum, the sun may go many days with no sunspots visible. [DOC] [TLE] Sunspots - Bob the Alien's Tour of the Solar System [PAR] These areas are cooler than the rest of the Sun's surface. ... doing so reveals that 
scattered across its visible surface (the photosphere) are dark spots. ... Sunspots 
can vary greatly in size and the length of time that they are present for. ... A 
sunspot can be present on the Sun for anything from a few days to several 
months. [DOC] [TLE] The Sun - NMSU Astronomy [PAR] Sometimes the Sun has few spots (it is "quiet", left), and sometimes many ... The 
dark linear and curved features are due to hydrogen gas that is above the ... The 
surface of the Sun that we see in the visible part of the spectrum is called the ... 
The gas follows these magnetic loops, and that's why some prominences are... [DOC] [TLE] The Sun's Magnetic Field | Explore - Cosmoquest [PAR] Jan 9, 2014 ... In a period of minimal sunspots, the few visible spots are grouped within ... After a 
few years, the sunspot number reaches a maximum and the spots are at ... 
Earth's magnetic field reverses every few hundred thousand to few million years. 
... These dark spots are sometimes visible to the naked eye when the... [DOC] [TLE] The Earth's Climate - CNRS sagascience -All the texts [PAR] These factors produce different climatic zones, which in turn affect the distribution 
... while infrared rays and visible light are partly reflected by the atmosphere and 
clouds. ... variations in the number of sunspots (of dark patches on the Sun's 
surface). ..... At depths comprised between a few dozen and several hundred 
meters,... [DOC] [TLE] The Sun - University of Northern Iowa [PAR] Even though the Sun is pretty much a big gas ball and has no solid surface, the 
photosphere ... The Sun's visible light spectrum showing absorption lines. ... As in 
many things in astronomy, it's all relative - the layer that is cooler just has to be .... 
When there are very few spots (at sunspot minimum), the spots tend to be seen... [DOC] [TLE] Astronomy Notes 2 - Motions of the Sun and the Moon [PAR] These days are also the dates that the Sun travels a path that is also an extreme - 
very long and ... those constellations are no longer visible since they are too 
close to the Sun, but ... The declination of the Sun varies throughout the year. .... 
The North pole star (Polaris) will not be there all the time - in a few hundred years 
the... [DOC] [TLE] The Sun and

Question: The number of these dark patches visible on the sun's surface varies from a few to several hundred
Answer: Sunspots