Visual Tour of the Solar System
Visual Tour of the Solar System -
Sun - Visual Solar System Tour - The Sun
The Greeks named the sun Helios, but the
Romans used the name Sol, which is still in use today. Due to
the important role the sun plays in our lives, it has been
studied, perhaps, more than any other object in the universe,
outside our own planet Earth.
The Sun is the closest star to Earth. It is by
far the largest object in the solar system, and contains more
than 99.8% of the total mass of the Solar System (Jupiter
contains most of the rest). Its strong gravitational pull holds
Earth and the other planets in the solar system in orbit.
Our Sun is considered to be an average star,
meaning its size, age, and temperature fall in about the middle
of the ranges of these properties for all stars. It is only 4.6
billion years old. Some of its material came from former stars.
This image, "Handle-shaped Prominence",
Extreme Ultraviolet Imaging Telescope (EIT) image of a huge,
handle-shaped prominence taken on Sept. 14,1999. Prominences are
huge clouds of relatively cool dense plasma suspended in the
Sun's hot, thin corona. At times, they can erupt, escaping the
Sun's atmosphere. Emission in this spectral line shows the upper
chromosphere at a temperature of about 60,000 degrees K. The
hottest areas appear almost white, while the darker red areas
indicate cooler temperatures.
Let's head outward from the sun to the first
planet in our solar system, Mercury.
Visual Tour of the Solar System - Mercury
The closest planet to the Sun, Mercury was named
after the Roman god of commerce, travel and thievery. The
existence of this 8th largest planet has been known of since
before the third century BC. The Greeks gave it two names,
Apollo for when it appeared as a morning star and Hermes when it
came as an evening star.
Mercury - Visual Solar System Tour -
Mercury is a planet of extremes. It speeds
around the Sun in a wildly elliptical (non-circular) orbit that
takes it as close as 47 million km and as far as 70 million km
from the Sun. The planet completes a trip around the Sun every
88 days, speeding through space at nearly 50 km per second,
faster than any other planet. Because it is so close to the Sun,
temperatures on its surface can reach a scorching 467 degrees
Celsius. But because the planet has hardly any atmosphere to
keep it warm, nighttime temperatures can drop to a frigid -183
Mercury has no known moons or satellites.
This Image of "Mercury" was produced from USGS
After Mercury, we head further away from the
sun to reach Venus.
Visual Tour of the Solar System - Venus
Venus, whose Greek equivalent was Aphrodite, was
the Roman goddess of love & beauty and probably gave her name to
the planet because it was the brightest object in the sky
besides the Sun & Moon. At one time, it was considered two
separate bodies: the morning star, Eosphorus and the evening
star. Hesperus. The 2nd planet from the Sun, it's the 6th
Venus - Visual Solar System Tour - Venus
At first glance, if Earth had a twin, it would
be Venus. They are similar in size, mass, composition, &
distance from the Sun. But there the similarities end. Venus has
no ocean and is covered by thick, rapidly spinning clouds that
trap surface heat, creating a scorched greenhouse-like world
with temperatures hot enough to melt lead and pressure as
intense as that felt 900 meters deep in Earth's oceans.
Venus has no known satellites, but between the
1670s and 1770s, there were several observations of what
appeared to be a satellite approximately ¼ the size of Venus.
However, recent observations have not revealed any satellite.
This Image of "Venus" is Centered at 0 degrees
east longitude, Magellan synthetic aperture radar mosaics from
the 1st cycle of Magellan mapping are mapped onto a
computer-simulated globe to create this image. Gaps are filled
with Pioneer Venus Orbiter data, or a constant mid-range value.
Simulated color is used to enhance small-scale structure.
Next, we'll be passing our home planet, Earth.
Visual Tour of the Solar System - Earth
Earth comes from Old English & Germanic. In Roman
Mythology, the goddess of the Earth was Tellus - the fertile
soil, while the Greek goddes was Gaia, terra mater - Mother
Earth. Earth is the only planet whose name is not derived from
Greek/Roman mythology and the only planet in our solar system
known to harbor life. All of the things we need to survive are
provided under a thin layer of atmosphere that separates us from
the uninhabitable void of space.
Earth - Visual Solar System Tour - Earth
Early philosophy had the Earth as the center
of the universe, but Aristarchus of Samos, in the 3rd Century
B.C., figured out how to measure the distances to and sizes of
the Sun and the Moon, and concluded that the Earth orbited the
Sun. This view didn't attract followers until Nicolaus
Copernicus, a Polish astronomer, published "On the Revolutions
of the Celestial Spheres" in 1543.
Earth has only 1 natural satellite, the Moon
at a distance of 384,000km, with a radius of 1738KM and a mass
of 7.32e22kg. However, there are thousands of small artificial
satellites which have been placed in orbit around the Earth.
Also, asteroids 3753 Cruithne and 2002 AA29 have complicated
orbital relationships with the Earth. They're not really moons,
the term "companion" is used.
This Image, "Hurricane Andrew" was taken on
August 25, 1992 by NOAA GOES-7 weather satellite of the Americas
and Hurricane Andrew as it makes landfall on the Louisiana
After we leave our home world, we head farther
out in the solar system to Mars.
Visual Tour of the Solar System - Mars
Mars was probably named for the Roman god of War
due to its red color. Sometimes called the Red Planet, Mars has
inspired wild flights of imagination over the centuries, as well
as intense scientific interest. From source of hostile invaders
of Earth to a rough-and-tumble mining colony of the future, Mars
provides fertile ground for science fiction writers.
Mars - Visual Solar System Tour - Mars
Mars' atmosphere is 95 % carbon dioxide,
nearly 3 % nitrogen, and nearly 2 % argon with trace quantities
of oxygen, carbon monoxide, water vapor, ozone, & other trace
gases. The average temperature is about -55C or -67F but can
range from -133C or -207F at the winter pole to almost 27C or
80F on the day side during summer. Orbiting 227,940,000 km (1.52
AU) from Sun, the Martian year is nearly 2 Earth years, while
its day is only about half an hour longer than Earth's.
Mars has 2 tiny satellites which orbit very
close to the surface, Phobos & Deimos.
This Image of "The Red Planet" is a composite
of Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) daily
global images acquired at Ls 193° during a previous Mars year
shows the Tharsis face of Mars. Ls, solar longitude, is a
measure of the time of year on Mars. Mars travels 360° around
the Sun in 1 Mars year. The year begins at Ls 0°, the start of
northern spring and southern autumn.
After the Red Planet, Mars, we travel even
farther out to the giant planet, Jupiter.
Visual Tour of the Solar System - Jupiter
Named after Jove, chief god of Roman mythology, Jupiter is the
5th planet from the Sun and the largest. After the Sun, Moon, &
Venus, it is the brightest object in the sky, often mistaken as
a star. It is more than 3 times brighter than Sirius, the
Jupiter - Visual Solar System Tour - Jupiter
Galileo was the 1st astronomer to view Jupiter through a
telescope. He observed 4 satellites orbiting the planet, which
supported to the Copernican theory that the Earth and other
planets revolve around the Sun. Galileo's discovery was a major
step forward for astronomy.
With its numerous moons and several rings, the Jupiter system
is a "mini-solar system." Many smaller moons have been
discovered recently, but are as yet unnamed. Known named moons
include: Metis, Adrastea, Amalthea, Thebe, Io, Europa, Ganymede,
Callisto, Leda, Himalia, Lysithea, Elara, Ananke, Carme,
Pasiphae, and Sinope.
This Image of "Jupiter" is a true-color simulated view of
Jupiter, composed of 4 images taken by NASA's Cassini spacecraft
on December 7, 2000. To illustrate what Jupiter would have
looked like if the cameras had a field-of-view large enough to
capture the entire planet, the cylindrical map was projected
onto a globe. Jupiter's moon Europa is casting the shadow on the
Cassini is a cooperative mission of NASA, the European Space
Agency and the Italian Space Agency.
From the giant, Jupiter, our mission continues out to that
ringed wonder, Saturn.