S
satellites - Satellites are objects that orbit a planet or a moon.
Many man-made satellites and one natural satellite (the Moon) orbit the Earth
Sagittarius - Sagittarius
is the ninth constellation of the zodiac. To the ancients, it represented a
centaur (half-man, half-horse) archer who was aiming at the Scorpion (the next
constellation) which bit Orion. Its central section (the archer's chest) also
resembles a teapot.
scatter (scatter) verb -
to cause to separate or break up
scientific (sci·en·tif·ic)
adjective - of, relating to, or exhibiting the methods or principles of
science
scintillation (scin·til·la·tion)
noun - rapid changes in the brightness of a celestial body
scorched (scorch) verb-
damaged or discolored by superficial burning
sea level noun - the level
of the surface of the sea especially at its mean position midway between mean
high and low water
sextant (sex·tant) noun -
an instrument for measuring angular distances used especially in navigation to
observe altitudes of celestial bodies (as in ascertaining latitude and
longitude)
Shapley, Harlow (1885-1972)
was an American astronomer who was the first person to accurately estimate the
size of the Milky Way Galaxy and our position in it.
shooting stars - A
shooting star is not a star; it is a meteor (made of rock and/or iron) which
is burning up in the Earth's atmosphere.
sister planet – Venus is
sometimes regarded as Earth’s sister planet. In some ways they are very
similar: Venus is only slightly smaller than Earth (95% of Earth's diameter,
80% of Earth's mass. Both have few craters indicating relatively young
surfaces. Their densities and chemical compositions are similar. Because of
these similarities, it was thought that below its dense clouds Venus might be
very Earth-like and might even have life. But, unfortunately, more detailed
study of Venus reveals that in many important ways it is radically different
from Earth.
space telescope - The
Hubble Space Telescope is a powerful telescope in orbit around the Earth. HST
transmits pictures and spectra of objects in space without the interference of
the atmosphere (which makes telescopic images from the ground have less
detail). It was launched into space in April 1990 and was repaired in
December, 1993.
speed - Speed is a measure
of how fast something is moving.
Solar System - A solar
system is a group of planets, moons, asteroids, and comets that orbit around a
sun. In our solar system, nine planets, over 61 moons, and many other objects
orbit around our Sun
solar power panels - the
ability to create energy from the Sun; these panels can capture light and
convert to electrical energy
spectral type Spectral
classes are groups of stars that have similar characteristic emission lines in
their spectra (indicating that they have similar compositions).
spectrum - The spectrum is
the band of colors that composes white light, in the order: red, orange,
yellow, green, blue, indigo, violet (from long to short wavelength). Newton
first discovered that sunlight could be divided into the visible spectrum.
spiral (spi·ral) adjective
- which one of or relating to the advancement to higher levels through a
series of cyclical movements; Spiral galaxies are galaxies with a central,
dense area and spiraling arms. There are two types of spiral galaxies,
"S" (normal spiral) and "SB" (barred spiral, with an
elongated center). The Milky Way and Andromeda Galaxy are two of a multitude
of known spiral galaxies.
star - A star is a ball of
hot gas held together by its own gravity. Gravity also causes stars to undergo
nuclear fusion within their interiors. The energy release associated with this
fusion causes the star to shine.
Stonehenge - was built in
several stages from 2800 - 1800 BC. It seems to have been designed to allow
for observation of astronomical phenomena - summer and winter solstices,
eclipses, and more.
streaming tails -
pertaining
to a long, lighted area that starts from the head of a comet and then trails
behind, caused by encounter with Sun’s rays
sulfuric acid droplet -
drops of water mixed with a strong acid
superheated (su·per·heat)
transitive verb - to heat (a vapor not in contact with its own liquid) so as
to cause to remain free from suspended liquid droplets; to heat (a liquid)
above the boiling point without converting into vapor
supernova - A supernova is
a huge explosion that occurs at the end of a mid- to heavy-weight star's life.
A supernova releases a tremendous amount of energy, expelling the outer layers
of the star and becoming extremely bright. What remains is a neutron star
(from a supergiant star) or a black hole (from a middle-weight star). |