Physics Project
Group members: Amen Belayneh
Hasset Daniel
Mela Bruk
Heyaw Tekeba
Nathnael Mehari
Uranus
What is Uranus, and where is it found?
Uranus is the third-largest planet by diameter, and it's known for its bluegreen color, which comes from the methane in its atmosphere. It's about
four times the size of Earth and has a diameter of about 31,500 miles
(50,700 kilometers).
Uranus is the seventh planet from the Sun in our solar system.
Uranus is located beyond the asteroid belt, between Saturn and Neptune,
in the outer region of our solar system. To give you a sense of distance,
it’s about 1.9 billion miles (3 billion kilometers) away from the Sun.
Magnetic Field
Uranus has a very unusual magnetic field compared to the other planets in our
solar system. Here’s a breakdown of its magnetic polarity and some of its unique
features:
1.)Off-Centered Dipole: Unlike Earth's magnetic field, which is relatively aligned
with its rotational axis, Uranus's magnetic field is tilted by about 59 degrees
relative to its rotational axis. This means the magnetic poles are not aligned with
the planet's equator, creating an unusual, tilted magnetic field.
2.)Complex and Irregular Field: Uranus's magnetic field is also highly irregular.
This is quite different from other planets, like Earth, which have relatively
straightforward magnetic field structures. The field is thought to be generated by
convection currents of conductive materials in Uranus’s icy mantle, though the
details are still not entirely understood.
Gravity and mass
The gravity of Uranus is about 8.69 m/s² (meters per second squared), which is
approximately 0.89 times the gravity of Earth.
To put that in perspective
On Earth, gravity is about 9.81 m/s².
On Uranus, if you weighed something that was 100 kg (about 220 lbs) on Earth, it
would weigh about 89 kg (196 lbs) on Uranus.
Mass
The mass of Uranus is approximately 8.68 × 10²⁷ kg (or 86.8 x 10²⁶ kg). This is
about 14.5 times the mass of Earth. Earth’s mass is about 5.97 × 10²⁴ kg.
Volume and circumference
The volume of Uranus is approximately 6.83 × 10¹³ km³ (cubic kilometers).
For comparison:
Earth’s volume is about 1.08 × 10¹² km³.Uranus is about four times the diameter of Earth, so it
has a volume that’s about 63 times greater than Earth's, even though its mass is not as much as
Jupiter or Saturn.
Circumference
The circumference of Uranus is approximately 159,000 kilometers (or about 98,000
miles). This is measured around the planet's equator, since Uranus is not a perfect sphere,
but an oblate spheroid (meaning it's slightly flattened at the poles and bulging at the
equator).
Rotational speed
Rotational speed(Day length)
Uranus takes about 17.24 hours to complete one full rotation on its axis. So, a "day"
on Uranus is just a bit shorter than a day on Earth.
Rotational speed
The rotational speed varies depending on the latitude, but at the equator, Uranus's
rotational speed is approximately 9.6 km/s (about 34,560 km/h or 21,500 mph).
This is quite fast when compared to Earth’s equatorial rotational speed of about 0.465 km/s
(about 1,670 km/h or 1,040 mph).
Revolutional speed
Orbital period
Uranus orbital period is about 84 Earth years (this means
it takes Uranus about 84 years to go around the Sun once).
Revolutional speed
Uranus orbits the Sun at an average speed of about 6.81 km/s
(about 24,500 km/h or 15,200 mph).
This is much slower than Earth’s orbital speed of about 29.78 km/s
(107,000 km/h or 66,600 mph), because Uranus is much farther from
the Sun, so it takes a much longer time to travel around it.
Surface temperature and Atmosphere
Since Uranus is the seventh planet from the sun, it is very cold…
so ,the average surface temperature of Uranus is around -224°C (about -371°F),
making it one of the coldest planets in our solar system.
Atmosphere
The atmosphere is mostly hydrogen, helium, and methane, which gives it
its blue-green color. Methane absorbs red light, reflecting blue and green
wavelengths back into space.
Chemical composition
The chemical composition of Uranus is primarily made up of
hydrogen, helium, and methane, with trace amounts of other
compounds.
Hydrogen makes up about 83% of Uranus's atmosphere by volume.
Helium makes up about 15% of the atmosphere by volume.
Methane makes up about 2% of Uranus’s atmosphere by volume.
Moons
Uranus has 27 moons, but here are the most known ones:
Titania: The largest moon of Uranus, with a diameter of about 1,578 km (980 miles). It has a
surface covered with large canyons, ice, and craters.
Oberon: The second-largest moon, which is about 1,523 km (946 miles) in diameter. Its
surface is also covered with craters and has large, deep valleys.
Miranda: One of the most unusual moons, with a highly varied surface, featuring cliffs,
canyons, and valleys. It’s about 471 km (293 miles) in diameter.
Ariel: This moon is notable for having the brightest surface of all Uranus’s moons, covered with
ice and rock. It has a diameter of about 1,158 km (720 miles).
Umbriel: One of the darkest moons, with a surface that is largely unaltered. It has a diameter o
about 1,170 km (727 miles).
Mythical representation
Uranus is a figure from Greek mythology and is the personification of the sky. He
was one of the primordial deities, created from Chaos (the void or nothingness) and was
the father of several important gods.
Uranus was the son and husband of Gaia, the personification of the Earth. Together,
they had many children, including the Titans, the Cyclopes, and the Hecatoncheires
(giants with 100 arms).
He was a powerful figure who ruled over the heavens, but his reign was marked by
cruelty. He feared the power of his children, so he imprisoned them deep within the
Earth, which caused Gaia great distress.
In retaliation, Gaia conspired with her son Cronus, who castrated Uranus with a sickle,
overthrowing him and casting him into the sea. After Uranus's castration, his blood
gave rise to various mythical creatures, including the Furies and Giants.
States of matter
Uranus exhibits multiple states of matter due to its extreme temperatures
and pressures. The upper atmosphere is composed of gases like
hydrogen, helium, and methane, existing in their gaseous state due to low
pressure and frigid temperatures around -224°C.
Deeper within the planet, as pressure increases, these gases transition
into liquid hydrogen and helium, while a layer of ices (water, ammonia,
and methane) forms, existing in a liquid state despite the cold.
The interior consists of a dense, icy mantle and a rocky core, where
higher pressures and temperatures cause substances to remain in liquid
or solid forms, creating a complex mixture of gas, liquid, and ice.
Pluto; The Failed Planet
When was Pluto First Discovered?
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Pluto was first discovered in February 18, 1930 by Clyde Tombaugh at the Lowell
Observatory in Flagstaff, Arizona.
What Made Us Believe Pluto was a Planet?
1. At the time, Astronomers had been searching for a ninth planet (temporarily
nicknamed planet x) to explain the irregularities that had been occurring in
Neptune's orbit. Pluto seemed to fit in the equation.
2. Pluto was initially thought to be the size of the Earth, but was later on measured to be
around ⅙ th of the Moon’s size.
3. Pluto orbits the sun like the other planets too, but its orbit is more elliptical and tilter
compared to the others.
4. In 1930, the definition of what a requirements objects in space needed to fulfill to be a
planet were vague; anything that orbited the Sun and wasn’t an asteroid or moon was
considered a Planet.
Who made the Decision?
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In August 24, 2006, the International Astronomical Union (IAU) decided in their
general assembly in Prague that Pluto was no longer a planet and had it reclassified as
a dwarf planet.
Facts about Pluto
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Pluto does not currently have any magnetic parity.
Pluto’s gravity is about 0.62 m/s²
, about 8% of Earth’s gravity. This means objects on Pluto weigh
significantly less that they would on Earth.
Pluto’s mass is approximately 1.309 × 10²² kilograms. This is a very small
fraction of Earth’s mass.
Pluto’s volume is approximately 6.39 x10⁹ km³.
Pluto's circumference is roughly about 7,232 km.
Pluto takes about 6.4 days to complete a full rotation and 248 years to
complete a full revolution around the sun.
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Pluto’s surface temperature is about -375 to -400 degrees Fahrenheit, the fact that
Pluto is very far away from the sun greatly contributes to this fact.
Pluto has a thin atmosphere.
Pluto’s surface is primarily a mixture of ices and rock, the dominant ices being
nitrogen ice, methane ice and water ice.
Pluto has 5 natural satellites; Charon, Styx, Nix, Kerberos and Hydra.
The mythical representation of the word Pluto, we refer the to Roman god Pluto, who
is closely related to the Greek god Hades. The Roman god Pluto is the god of the
underworld and is strangely associated with money, too.
The states of matter found in Pluto are: Solid and gas.
Pluto’s distance varies significantly because of its elliptical orbit. Its average distance
from the sun is approximately 3.7 billion miles (5.9 billion kilometers) or about 39
astronomical units (AU).
The Sun
What is the sun?
The Sun is a massive ball of hot plasma at the center of our solar system.It is about
4.6 billion years old and will continue burning for another 5 billion years.It makes up
99.8% of the total mass of the solar system!
The Sun is a big ball of super-hot gas and a medium-sized star compared to
others in space. It spins, but because it’s not solid, different parts spin at
different speeds—this is called differential rotation. The Sun constantly sends
out solar wind, a stream of tiny charged particles that travel far into space and
can create the Northern and Southern Lights when they hit Earth’s
atmosphere. Every 11 years, the Sun goes through an activity cycle, where it
gets more sunspots, solar flares, and explosions called coronal mass
ejections. In about 5 billion years, the Sun will swell up into a huge red giant,
swallowing Mercury, Venus, and maybe Earth before shrinking into a white
dwarf, leaving behind a glowing cloud of gas. Even though the Sun is
incredibly powerful, it’s just one of billions of stars in our galaxy, the Milky Way!
More about the Sun..
The Sun’s gravity is so strong that it keeps all the planets,
moons, and even distant comets in orbit around it. It makes up
about 99.8% of the total mass of the solar system, meaning
almost everything in our solar system comes from leftover
material after the Sun formed. The Sun’s surface isn’t solid—it’s
a boiling sea of plasma with powerful magnetic fields that can
twist and snap, causing massive solar storms. It also emits
ultraviolet (UV) radiation, which can be harmful to human skin
but is mostly blocked by Earth’s atmosphere. Scientists study the
Sun using spacecraft like NASA’s Parker Solar Probe, which is
flying closer to the Sun than any spacecraft in history to learn
more about its outer layers. Even though the Sun looks yellow
from Earth, it’s actually white, but our atmosphere scatters the
light, making it appear more yellow or orange.
Neptune
Where is Neptune found?
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Neptune is the eigth planet of our solar system, making it the furthest planet
from the Sun. It orbits the sun at a distance of 2.8 billion miles or 4.5 billion
kilometres.
Since it's so far from the sun, it's temperature is known to be the lowest our of
the eight planets.
Who discovered Neptune?
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Neptune was first ever sited in 1612 & 1613 by Galileo Galilei, but he had
mistaken it to be a star and hadn't observed any further.
Later on, Urbain Le Verrier and John Couch Adams had independently
calculated and predicted the planets position based on the irregularities in
Uranus’s orbit.
Facts about Neptune
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Neptune's polarity is essentially the complete opposite of Earth's polarity.
Neptune's gravity is about 11.15 m/s², which js about 1.14× Earth's.
Neptune's mass is around 1.024 × 10²⁶ kilograms, about 17× Earth's mass.
Neptune's volume is about 6.253 × 10¹³ km³ (about 57.74 times Earth's
volume) and it's circumference is approximately 49,244 km.
It takes Neptune 16 hours to finish 1 rotation and 165 Earth years to finish
one orbit around the Sun.
The temperature for Neptune's upper atmosphere is usually around -214°C,
while it can range from -218°C (min) to -201°C (max).
Neptune's atmosphere is mainly made up of Hydrogen and Helium gas with
traces of methane, which is what gives the atmosphere its blueish colour.
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As of now, Neptune has 14 moons, three examples being Triton, Proteus and
Nereid.
Neptune's mythical representation is usually associated with the Roman god
Neptune, also known as Poseidon in Ancient Greek.
In Neptune, solid, liquid, gas and ice cream the states of matter that exist to
our knowledge.