Planetary Physics Studio
Explore the physics of the cosmos. See how Gravity affects your weight, how Time (years) flows differently on other worlds, and the scale of Interplanetary Travel.
Your Weight on Other Worlds
Gravity varies wildly across the solar system. How much would you weigh?
The Physics of Other Worlds
When we look at planets through a telescope, they look like static balls in the sky. But each one is a dynamic physical environment with its own rules of gravity, time, and motion. This studio helps you experience those differences firsthand.
The Weight of Gravity
Your Weight is just the force of the planet pulling you down. On Mercury, you'd feel light as a feather, able to jump three times higher than on Earth.
On Jupiter, the gravity is so intense (2.4x Earth's) that you would struggle just to stand up. Your bones would have to support more than double your normal weight!
Time is Relative
Not in the sci-fi sense, but in the calendar sense. Because outer planets like Neptune take 165 Earth years to orbit the Sun, a "year" there is a lifetime here.
If you lived on Neptune, you wouldn't even have your first birthday until you were 165 years old in Earth time!
The Challenge of Space Travel
Space is big. Really big. Our "Cosmic Travel" calculator demonstrates why human exploration is so difficult.
Even at the speed of a jet plane (900 km/h), it would take nearly 19 years just to reach the Sun. Converting that to space travel, the Voyager 1 probe is traveling at a staggering 61,500 km/h, yet it still took years to reach the gas giants.
The Gravity Well
Leaving Earth is the hardest part. To escape Earth's gravity and get to space, a rocket must reach "Escape Velocity"—about 40,000 km/h. That's why rockets are mostly fuel tanks!
Frequently Asked Questions
Why would I weigh less on Mars?
Weight is a measure of the gravitational force pulling on your mass. Since Mars has less mass than Earth (about 11%), its gravitational pull is weaker (only 38% of Earth's). So, if you weigh 100kg on Earth, you'd feel like you weigh only 38kg on Mars.
Does my mass change on other planets?
No! This is a common misconception. Your mass (the amount of matter in your body) stays exactly the same whether you are on Earth, the Moon, or floating in deep space. Only your weight (the force) changes depending on gravity.
Why is a year on Mercury only 88 days?
A 'year' is defined as the time it takes a planet to complete one full orbit around the Sun. Because Mercury is much closer to the Sun (0.39 AU), it travels a shorter distance and moves faster due to the Sun's strong gravity, completing a lap in just 88 Earth days.
Could we actually travel to Neptune?
With current technology, it is extremely difficult. Voyager 2 took 12 years to reach Neptune using gravity assists. A direct human mission would require new propulsion technology to make the journey in a reasonable timeframe, not to mention surviving the radiation and isolation.
Why is Jupiter's gravity so strong?
Jupiter is massive—318 times the mass of Earth. Since gravity is directly proportional to mass, Jupiter exerts a much stronger pull. However, since it's a gas giant with no solid surface, your 'weight' is calculated at the cloud tops where atmospheric pressure equals 1 bar.
How long is a day on Venus?
Venus has a very slow rotation. It takes 243 Earth days to spin once on its axis. Interestingly, its year (orbit around the Sun) is only 225 days. This means a day on Venus is actually longer than its year!
What is the fastest object humans have built?
The Parker Solar Probe holds the record. As it dives towards the Sun, it reaches speeds of over 635,000 km/h (394,000 mph). At that speed, you could fly from New York to Tokyo in under a minute.
Does gravity affect time?
Yes, according to Einstein's General Relativity. Time moves slower in stronger gravitational fields (Time Dilation). However, for planets in our solar system, this effect is microscopic compared to the difference in orbital periods (years).
How much would I weigh on the Sun?
If you could stand on the Sun without burning up instantly, you would weigh about 27 times more than on Earth. A 70kg person would feel like they weighed nearly 2 tons!
Why are light years used for distance?
Space is so vast that kilometers become unmanageable numbers. A light year is the distance light travels in one year (about 9.46 trillion km). It helps astronomers measure distances to stars effortlessly.