Astronomy Notes – Unit 1 – Sun
WARNING: Never, ever look directly at the Sun,
especially with binoculars or telescopes!
q (1) The Sun is the nearest star to Earth, at an average distance of _________ miles (150 million kilometers). Since the speed of light is _______________________, it takes about _______________ for light from the Sun to reach the Earth.
q (2) The diameter of the Sun is 875,000 miles (1.4 million kilometers). It could hold more than __________ Earths.
q (3) The surface gravity of the Sun is about ____ times that of the Earth.
q (4) The Sun produces huge amounts of energy, including light and heat, from a process called nuclear fusion. This process joins pairs of ____________ atoms into ___________ atoms.
q (5) Scientists believe the temperature of the Sun varies from ___________ degrees Fahrenheit (15 million degrees Celsius) at the core, to ________ degrees Fahrenheit (5,500 degrees Celsius) at the surface, or photosphere.
q (6) The corona (Latin for crown) is the outer part of the Sun’s atmosphere, and is visible during a ______________.
q (7) The Sun’s average period of rotation about its axis varies from ________ at the equator to __________ at higher latitudes.
q (8)
A sunspot
is a temporary, darker, cooler patch on the surface of the Sun. These are
believed to be caused by magnetic fields that impede hot gases from rising to
the surface. They last about a week or
so. A typical sunspot is about the
_____________ or larger.
q (9)
Massive, violent explosions of hot _________ on the Sun’s surface are called solar
flares. These can last from a few minutes to a few hours.
q (10) The Sun continually emits a stream of high energy, electrically charged particles called the solar wind. Near Earth, the average speed of the solar wind is about ___________________ (450 million kilometers/hour).
q (11)
The limit of the solar wind extends beyond the orbit of
q (12) The Earth’s magnetic field protects us from the solar wind. These particles cause colorful, rippling lights called aurora borealis, or _______________ near the north pole, and aurora australis, or ______________ near the south pole.
q (13) Surges in the solar wind caused by solar flares can disrupt communications and power transmission here on Earth.
q (14) Ultraviolet radiation from the Sun causes suntan and sunburn, and may be a factor in causing ______________.
1) Solar Wind:
______________________________________________________
__________________________________________________________________
2) Solar Flare:
______________________________________________________
__________________________________________________________________
3) Sunspot: _________________________________________________________
__________________________________________________________________
4) Photosphere:
_____________________________________________________
__________________________________________________________________
5)
__________________________________________________________________
6) Astronomical Unit (A.U.): __________________________________________
__________________________________________________________________
7) Solar Prominence: _________________________________________________
__________________________________________________________________
8) Nuclear Fusion:
___________________________________________________
__________________________________________________________________
9) Aurora Borealis (Northern Lights): __________________________________
__________________________________________________________________
10) Aurora Australis (Southern Lights): __________________________________
__________________________________________________________________