what if you jumped into a 7,964 mile deep hole;
a hole that came out on the other side globe?
and if you were ever to stop, how fast and how far
would you have traveled?
and how much time would your journey have taken?
for the answers to these questions, check out the
video below, an excerpt from the History Channel’s
The Universe, Gravity
Galileo Galilei was the first to observe the rings of
Saturn when, in 1610, he turned his 20-power tele-
scope toward the planet the Romans had named
Saturnus, after the god of agriculture
Galileo assumed that the rings were “handles” or
large moons positioned on either side of the planet
He wrote,
“I have observed the highest planet [Saturn] to be tripled-bodied. This is to say that to my very great amazement Saturn was seen to me to be not a single star, but three together, which almost touch each other”.
- NASA
today, we know that the rings are not any of the
more than 60 moons that orbit the planet -
but what are they?
from the data gathered by Pioneer 11, Voyager 1,
Voyager 2 and Cassini–Huygens we now understand
the following -
- the rings are 173,000 miles in diameter, with a
thickness of less than 70 feet
- they consist of billions of pulverized particles that
range in size from specks smaller than a grain of
sand to boulders larger than a house
- the particles are comprised mainly of water ice
- they race around the planet, colliding into one
another in a cosmic roller derby
- and they move at speeds that range from 20,000 to
40,000 mph; that’s somewhere between 25 and 50
times faster than the speed of sound
for more on the rings, from the men and women
who study them, check out the video below
the above video is a brief excerpt of the History
Channel’s The Universe
the density of Saturn is lower than that of any planet
in our solar system
in fact, its density (0.687 g/cm³) is lower than that of
water (0.998 g/cm³)
which means that if Saturn were to be plopped in
some some vast mega-ocean
it would float
an extrasolar planet is a planet that exists beyond
our solar system
to date, 277 such planets have been found; and
the rate of their discovery is increasing, with 61
found in 2007 alone
however, back in 1995, astronomers like Geoffrey
Marcy were having no luck finding planets that
orbited distant stars
and it seemed as though extrasolar planets were
either extremely rare, near-impossible to detect
or even nonexistent
but then on October 6, 1995, Swiss astronmers
Michel Mayor and Didier Queloz published a paper
in Nature announcing the discovery of a Jupiter-
sized planet orbiting a sun-like star, 51 Pegasi
within a week, the discovering was independently
confirmed Marcy and his team
the planet is called 51 Pegasi b and its parent star,
51 Pegasi
the star, located in the constellation Pegasus, can
be seen with the naked eye, though it is some
300 trillion miles from Earth
the planet, 51 Pegasi b, is unlike any in our solar
system in that it is Jupiter-like in size and compos-
ition, and yet it orbits extremely close to its parent
star with unheard of speed
the video below, an excerpt from a National Geo-
graphic documentary, provides greater detail on the
star, the planet, the astronomers and the discovery
the video below describes the gravitational effect of
a planet on the star it orbits
the narrator of the National Geographic documentary
states,
When a planet orbits a star, its gravitational force will pull the star off center; making it wobble from side to side . . .
to illustrate this phenomenon, the video references
the relative motions (or “the dance”) of Jupiter and
the Sun,
The largest planet in our solar system is Jupiter . . . 500 million miles out from the Sun, it take 12 years to complete each orbit. As it travels round, Jupiter pulls our sun off-center by as much as half a million miles.
