Planet Gravity

Gravity is derived from the Latin word ‘gravitas’ meaning mass. The universal law of gravitation was coined by Sir Isaac Newton. According to the law, any two masses anywhere in the universe separated by a distance will attract each other. This force of attraction is proportional to the product of their masses and inversely proportional to square of the distance between them.

According to this law, all objects that have mass will attract other masses. Extending this principle to planetary bodies, each planet in our Solar System, which has its own gravitational field will attract other masses. This app allows you to visualize the force of gravity of each planet by dropping an object such as an apple from a height of 1 meter.

There are 8 official planets in our Solar System which are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Planets Mercury, Venus, Earth and Mars are often referred to as inner planets and have a solid surface. Planets Jupiter, Saturn, Uranus and Neptune are referred to as outer planets. They do not have a solid surface. In fact, Jupiter and Saturn are Gas giants whereas Uranus and Neptune are Ice giants.

Planets in the Milky way galaxy beyond our Solar system are referred to as Exoplanets or Extrasolar planets. They too follow a planetary system similar to our solar system and are scattered several lightyears around us. A 'lightyear' is the distance traveled by light in one year. It is a unit of distance and not a unit of time. One lightyear is equal to 9.46 trillion kilometers!

There are different categories in Exoplanets such as Hot Jupiters, Super Earths, Trappist System, Super Puffs, Neptune Worlds, Super Gravity, etc. Hot Jupiters included in this app are Wasp-6b, Wasp-8c, Wasp-17b, Wasp-31b, Wasp-41c, Wasp-57b, HD 10180h, HD 189733b, GJ 1148 b and BD-1763 b.
Super Earths included in this app are 55 Cancri e, HD 20794 e, Kepler-22b, Kepler-65d, Kepler-249d, HIP 116454b, TOI-561e, YZ Ceti d, CoRoT-7 b and Kepler-452b.
A Natural Satellite is an astronomical body that orbits a planet. Satellites included in this app are Moon, Phobos, Lo, Callisto, Europa, Ganymede, Titan and Mimas.
Planets in the Trappist system are Trappist-1b, 1c, 1d, 1e, 1f, 1g & 1h.
Super Puffs included in this app are Kepler-51 b, Kepler-51 c, Kepler-51 d, Kepler-87 c and HIP 41378f.
Planets in Neptune Worlds are GJ 163D, BD+20 594B, GJ 676AE, GJ 876D, AU MicrocopiiB, HAT-P-11B, GJ 96B, GI 686B, HD 103949B and GJ 9689B.
Planets in Super Gravity are AB Pictoris b, CHXR 73 b, HD 100546b, HD 106906b and CoRoT-20c.

How to use this app?

- Click on Solar System and click on any of the 8 planets on screen to visit the particular planet of interest.
- Similarly, click on Hot Jupiters, Super Earths, Satellites or other categories and click on any of the displayed planets/satellites on screen to visit the particular planet/satellite of interest.
- Tap on the 'Apple' to get a perception of how fast or slow it falls, which is a direct consequence of how strong or weak the gravitational force of the planet is.
- In addition, tap the "Facts" button to learn some interesting fun facts about each planet and satellite!

Enjoy the app!

Photo Credits : NASA