3. Mythology
• The planet Jupiter has been known since ancient times. It is
visible to the naked eye in the night sky and can occasionally
be seen in the daytime when the sun is low.
• The Romans named it after Jupiter (Latin: Iuppiter, Iūpiter)
(also called Jove), the principal god of Roman mythology,
whose name comes from the Proto-Indo-
European vocative compound *Dyēu-pəter (nominative:
*Dyēus-pətēr, meaning "O Father Sky-God", or "O Father
Day-God").
4. • Jupiter is the fifth planet from the Sun and
the largest planet within the Solar System. It is a gas
giant with mass one-thousand that of the Sun but is two
and a half times the mass of all the other planets in our
Solar System combined.Jupiter is classified as a gas giant
along with Saturn,Uranus and Neptune. Together, these
four planets are sometimes referred to as the Jovian or
outer planets.
1. What are these
four planets that
referred to as the
Jovian or outer
planets.
5. When viewed from Earth, Jupiter can reach an apparent
magnitude of −2.94, making it on average the third-brightest
object in the night
sky after the Moon and Venus.
2. What is the 3rd brightest
object in the night sky after
the Moon and Venus?
6. • Jupiter is the most massive planet in our solar system, more
than twice as massive as all the other planets combined, and
had it been about 80 times more massive, it would have
actually become a star instead of a planet. Its atmosphere
resembles that of the sun, made up mostly of hydrogen and
helium, and with four large moons and many smaller moons in
orbit around it, Jupiter by itself forms a kind of miniature solar
system. All told, the immense volume of Jupiter could hold
more than 1,300 Earths.
7. Jupiter's mass is 2.5 times that of all the
other planets in our Solar System
combined—this is so massive that its bar
center with the Sun lies above the Sun's
surface at 1.068 solar radii from the Sun's
center. Although this planet dwarfs the
Earth with a diameter 11 times as great, it
is considerably less dense
8. Jupiter's Moons
• Jupiter has at least 63 moons, which are often named after
the Roman god's many lovers. The four largest moons of
Jupiter, now called Io, Europa, G anymede, and Callisto, were
discovered by Galileo himself, and are appropriately known
today as the Galilean satellites.
3. What are these four
Galilean satellites?
9. • Ganymede is the largest moon in our solar system,
larger even than Mercury. It is also the only moon known
to have its own magnetic field.
4. What is the
largest moon in our
solar system?
10. • Io is the most volcanically active body in our solar system.
The sulfur these volcanoes spew out gives Io a blotted yellow-
orange appearance that is often compared to a pepperoni
pizza. As Io orbits Jupiter, the planet's immense gravity
causes 'tides' in Io's solid surface that rise 300 feet (100
meters) high, generating enough heat for volcanic activity.
5. Whatis the most
volcanically active
body in our
system?
11. • The frozen crust of Europa is made up mostly of water ice,
and it might hide a liquid ocean holding twice as much water
as Earth does. Icy oceans might also exist beneath the crusts
of Callisto and Ganymede.
• Callisto has the lowest reflectivity, or albedo, of the four
Galilean moons. This suggests that its surface might be
composed of dark, colorless rock.
6. What moon is
made up mostly of
water ice?
7.What moon that it’s
surface might be
composed of dark,
colorless rock?
12. • Jupiter spins faster than any other planet,
taking a little under 10 hours to complete a
turn on its axis, compared with 24 hours
for Earth.
8. Jupiter has _____
to complete a turn
on it’s axis.
13. • The best known feature of Jupiter is the Great Red Spot, a
persistent anticyclonic storm that is larger than Earth, located 22°
south of the equator. It is known to have been in existence since at
least 1831,and possibly since 1665. Mathematical models suggest
that the storm is stable and may be a permanent feature of the
planet. The storm is large enough to be visible through Earth-
based telescopes with an aperture of 12 cm or larger.
14. The Great Red Spot, a giant hurricane-like storm seen for
more than 300 years. At its widest, the Great Red Spot is
three times the diameter of the Earth, and its edge
spins counterclockwise around its center at a speed of about
225 miles (360 kilometers) per hour. The color of the storm,
which usually varies from brick red to slightly brown, may
come from small amounts of sulfur and phosphorus in the
ammonia crystals in Jupiter's clouds. Every now and again,
the Great Red Spot seems to fade entirely.
15. Composition & Structure
• Atmospheric composition (by volume)
89.8 percent molecular hydrogen, 10.2 percent helium,
minor amounts of methane, ammonia, hydrogen
deuteride, ethane, water, ammonia ice aerosols, water
ice aerosols, ammonia hydrosulfide aerosols
• Magnetic Field
Nearly 20,000 times stronger than Earth's
16. • Chemical composition
A dense core of uncertain composition, surrounded by a
helium-rich layer of fluid metallic hydrogen, wrapped up
in an atmosphere primarily made of molecular hydrogen.
• Internal structure
A core less than 10 times Earth's mass (Tristan Guillot,
"Interiors of Giant Planets Inside and Outside the Solar
System." Science Vol. 286 (5437), p. 72-77, October 1,
1999.), surrounded by a layer of fluid metallic hydrogen
extending out to 80 to 90 percent of the diameter of the
planet, enclosed in an atmosphere mostly made of
gaseous and liquid hydrogen.
17. Orbit & Rotation
• Average Distance from the Sun
English: 483,682,810 miles
Metric: 778,412,020 km
By Comparison: 5.203 times that of Earth
• Perihelion (closest)
English: 460,276,100 miles
Metric: 740,742,600 km
By Comparison: 5.036 times that of Earth
• Aphelion (farthest)
English: 507,089,500 miles
Metric: 816,081,400 km
By Comparison: 5.366 times that of Earth
18. Jupiter's Rings
• Jupiter's three rings came as a surprise when NASA's
Voyager 1 spacecraft discovered them around the planet's
equator in 1979. Each are much fainter than Saturn's rings.
• The main ring is flattened. It is about 20 miles (30 kilometers)
thick and more than 4,000 miles (6,400 kilometers) wide.
9. What are
these three
Jupiter’s ring?
19. • The inner cloud-like ring, called the halo, is roughly 12,000 miles
(20,000 kilometers) thick. The halo extends halfway from the main
ring down to the planet's cloud tops and expands by interaction with
Jupiter's magnetic field. Both the main ring and halo are composed
of small, dark particles.
20. • The third ring, known as the gossamer ring because of its
transparency, is actually three rings of microscopic debris
from three of Jupiter's moons, Amalthea, Thebe and
Adrastea. It is probably made up of dust particles less than
10 microns in diameter, about the same size of the particles
found in cigarette smoke, and extends to an outer edge of
about 80,000 miles (129,000 kilometers) from the center of
the planet and inward to about 18,600 miles (30,000
kilometers).
21. Possibility of Life on the
Planet Jupiter
• If one were to dive into Jupiter's atmosphere, one would
discover it to grow warmer with depth, reaching room
temperature, or 70 degrees F (21 degrees C), at an altitude
where the atmospheric pressure is about 10 times as great as
it is on Earth. Scientists have conjectured that if Jupiter has
any form of life, it might dwell at this level, and would have to
be airborne. However, researchers have found no evidence of
life on Jupiter.
10. Is there any
evidence of life in
Jupiter?