The four outer planets, or giant planets (sometimes called Jovian planets), collectively make up 99% of the mass known to orbit the Sun. Jupiter and Saturn are together more than 400 times the mass of Earth and consist overwhelmingly of the gases hydrogen and helium, hence their designation as gas giants.

Each planet, including Earth, keeps to a roughly circular path, always maintaining the same distance from the sun. For decades, astronomers have wondered whether the solar system’s circular orbits might be a rarity in our universe.

All planets move in elliptical orbits, with the sun at one focus. This is one of Kepler’s laws. The elliptical shape of the orbit is a result of the inverse square force of gravity.

If a planet is close to the Sun, the distance it orbits around the Sun is fairly short. This distance is called an orbital path. The closer a planet travels to the Sun, the more the Sun’s gravity can pull on the planet. The stronger the pull of the Sun’s gravity, the faster the planet orbits.

The Sun’s enormous mass is held together by gravitational attraction, producing immense pressure and temperature at its core.

Neptune

FAQ – Spacecraft

No. The time-dilation effect of Einstein’s relativity has nothing to do with space. The faster you’re moving, the slower time goes for you. So if you were on some planet moving extremely fast through space, like in the movie Interstellar, then you could miss 7 years on Earth every hour.

Flying through outer space has dramatic effects on the body, and people in space experience aging at a faster rate than people on Earth. These studies showed that space alters gene function, function of the cell’s powerhouse (mitochondria), and the chemical balance in cells.

That’s 24 hours on Earth, 708.7 hours (29.53 Earth days) on the Moon.

23 hours and 56 minutes

Peggy Whitson set the record on Sept. 2, 2017, for most cumulative days living and working in space by a NASA astronaut at 665 days.

Time is measured differently for the twin who moved through space and the twin who stayed on Earth. The clock in motion will tick more slowly than the clocks we’re watching on Earth. If you’re able to travel near the speed of light, the effects are much more pronounced.

Astronauts when walk in space or any time an astronaut gets out of a vehicle while in space, it is called a spacewalk; of course apart from Michael Jackson’s hack. In the present times astronauts go on spacewalks outside the International Space Station (ISS).

While there are about 2,000 active satellites orbiting Earth at the moment, there are also 3,000 dead ones littering space. What’s more, there are around 34,000 pieces of space junk bigger than 10 centimetres in size and millions of smaller pieces that could nonetheless prove disastrous if they hit something else.

In space, not so much. Sensors inside our ears, which are part of the vestibular system that controls balance, are thrown off — often causing astronauts to feel dizzy or queasy the first few days in space. Once they get back to Earth, it takes a while for their bodies to readjust. Hence, the walking problems.

According to NASA, civilian astronauts are awarded a pay grade of anywhere from GS-11 to GS-14, so the income range is relatively wide. Starting salaries begin at just over $66,000 a year. Seasoned astronauts, on the other hand, can earn upward of $144,566 a year.

Walking around on Venus wouldn’t be a pleasant experience. The Venusian surface is completely dry because the planet suffers from a runaway greenhouse gas effect. Venus’ gravity is almost 91 percent of Earth’s, so you could jump a little higher and objects would feel a bit lighter on Venus, compared with Earth.

At least, you wouldn’t be able to live on Saturn like you’d live on Earth, or perhaps even Mars. Saturn is what we call a “gas giant.” It is a planet made up most of hydrogen and helium. This means that there is no solid surface on Saturn, Well, that we know of, anyway. Saturn doesn’t have any of that.

Like Earth, a large portion of Pluto’s atmosphere is made up of Nitrogen. Carbon Monoxide and Methane make up the rest of it. These gasses are highly toxic, making breathing on Pluto essentially impossible.

The sun won’t die for 5 billion years, so why do humans have only 1 billion years left on Earth? In a few billion years, the sun will become a red giant so large that it will engulf our planet. But the Earth will become uninhabitable much sooner than that.