Our Sun
Orbit
Jupiter travels once around the Sun every 12 years and spins on its own axis every 10 hours compared to 24 on Earth, making it the fastest spinning planet in the Solar System.
Atmosphere
The atmosphere of Jupiter is composed of about 86 percent hydrogen, 14 percent helium, and tiny amounts of methane, ammonia, phosphine, water, acetylene, ethane, germanium, and carbon monoxide.
Temperature
The temperature at the top of Jupiter's clouds is about -145C (-230F). Deeper below the clouds the temperate reaches 21C (70F). Near the planet's centre the temperature is hotter than the surface of the Sun!

Planet Jupiter Statistics
Diameter: 89,000 miles (143,000 km)
Average Distance from Sun: 484 million miles (779 million km)
Orbital Period: 12 years
Rotation Period: 9.93 hours
Moons: 63
Maximium Temperatures: 24,000C (43,000F) (Core)
Minumum Temperatures: -145C (-230F) (Cloud Tops)

Gravity: 20.87 m/s2 (2.14 x Earth's Gravity)
Density: 1.33 g/cm3 (24% Earth's Density)
Mass: 1.8987 x 1027 kg (318 x Earth's Mass)
Volume: 1.4255 x 1015 km3 (1316 x Earth's Volume)

Atmosphere: 86% Hydrogen, 14% Helium, 0.3% Methane, 0.026% Ammonia, 0.003% Hydrogen deuteride, 0.0006% Ethane, 0.0004% water.
Life of Our Sun
Red Giant
The bad news is that our sun will not exist forever, unfortunately like everything in the universe it has a life span. The good news is that it will continue in its current state for another 5 or 6 billion years. At the moment our sun is in the middle of its main sequence phase, meaning it is producing all its energy from hydrogen fusion in its core. This is the longest phase in the life of a star which lasts billions of years, in the case of our sun around 10 billion years. After this time the sun will run out of hydrogen, it will begin expanding to hundreds of times its original size and its surface will cool down turning it into a red giant (pictured left). This will result in the destruction of Mercury, Venus and Earth. It will exist as a red giant for around one billion years until eventually it will begin to lose its mass until only the core remains, this is called a white dwarf. It will remain in this state for billions of years until eventually it cools down and dies.
Our Nearest Neighbours
Proxima Centauri
Our sun is part of a single star system but actually this is not the norm in the galaxy. The majority of stars are part of a binary system which is two nearby suns orbiting each other. Our closest stellar neighbour Proxima Centauri (pictured left) is actually part of a multiple star system with Alpha Centauri A and B. Proxima Centauri is 25 trillion miles (40 trillion km) from our sun, even if we could travel at the speed of light it would still take over 4 years to reach it.

Proxima Centauri is a red dwarf star and these are by far the most common types of star in our galaxy. Red dwarfs have less than half the mass of the sun and are usually much smaller in comparison, Proxima Centauri is only around one seventh the size of our sun with only 10% of its mass. Whereas stars like our sun last only around 10 to 12 billion years red dwarfs exist for trillions of years. They are much cooler than our own sun and it seems unlikely they could support life in any orbiting planets.

One of the other stars in the Alpha Centuari system, Alpha Centauri A, is much more like our own sun. Planets orbiting close to this sun could enjoy habitable conditions similar to what we have on Earth. Any inhabitants living on this planet would have the striking image of three suns in its sky, the very bright Centauri A, the much smaller and dimmer orange coloured Centauri B and and the even smaller red dwarf star.

The Sun - Images and Videos
Solar flare
Solar flare
Sun Rotation (NASA)
Sun in our sky
Sun in our sky
The Sun - Vital Statistics
Comparison with Earth
Diameter: 864,000 miles (1.4 million km)
Distance from Centre of Galaxy: 25 million light years
Orbital Period: 250 million years
Rotation Period: 25.38 days

Maximium Temperatures: 15 million C (27 million F) (Core)
Minumum Temperatures: 5,500C (10,000F) (Photosphere)

Gravity: 274 m/s2 (28 x Earth's Gravity)
Density: 1.409 g/cm3 (25.5% Earth's Density)
Mass: 1.989 x 1030 kg (333,000 x Earth's Mass)
Volume: 1.412 x 1018 km3 (1.3 million x Earth's Volume)

Atmosphere (Photosphere): Hydrogen 73.46%, Helium 24.85%, Oxygen 0.77%, Carbon 0.29%, Iron 0.16%, Sulfur 0.12%, Neon 0.12%, Nitrogen 0.09%, Silicon 0.07%, Magnesium 0.05%.
Diameter: 7,926 miles (12,756 km)
Average Distance from Sun: 93 million miles (150 million km)
Orbital Period: 365.24 days
Rotation Period: 23.934 hours

Maximium Surface Temperatures: 58C (136F)
Minumum Surface Temperatures: -88C (-126F)

Gravity: 9.766 m/s2
Density: 5.515 g/cm3
Mass: 5.9737 x 1024 kg
Volume: 1.0832 x 1012 km3

Atmosphere: 78.08% nitrogen, 20.95% oxygen, 0.93% argon, 0.038% carbon dioxide, water vapour makes up on average around 0.4% of Earth's atmosphere depending on climatic conditions.
The Sun Compared to Earth in Size
sun compared to earth in size