# What does planet size determine?

## What does planet size determine?

The most common is to measure the apparent angular diameter of the planet – how big it looks against the sky – very precisely using a telescope. Combining this with a measure of its distance (deduced from its orbit around the Sun) reveals the planet’s actual size.

How does size affect a planet?

A planet’s size and mass determines its gravitational pull. A planet’s mass and size determines how strong its gravitational pull is. Models can help us experiment with the motions of objects in space, which are determined by the gravitational pull between them.

What is planetary orbital size?

What are the orbital lengths and distances of objects in our solar system?

OBJECT Distance from Sun (average) Amount of time for one complete orbit of the Sun (one “year.”)
Sun 0 miles
Mercury 36,800,000 miles 3 Earth months
Venus 67,200,000 miles 7 Earth months
Earth 93,000,000 miles 1 Earth year (365.25 days)

### Why are planets different sizes?

Planets come in different sizes and so have different gravity levels. Mars is smaller than Earth so has less gravity. On Mars you weigh less and would be able to carry more. Smaller planets are also less likely to have an atmosphere, as there may not be enough gravity to hold the gases to the surface.

What planet do you weigh the most on?

Jupiter
Jupiter is the largest planet in our Solar System with the most mass. Because of Jupiter’s mass, you would weigh more on that planet than on any other one in our Solar System. If you weighed 68 kg on Earth then you would weigh 160.7 kg on Jupiter, over twice your normal weight.

How are planetary orbits calculated?

Kepler’s Equation

1. M = M(0) + 360°(t/T) We assume the period T is known (this requires the 3rd law and is discussed for circular orbits in sections 20 and 20a).
2. M = E – (180°/π)e sinE. where π = 3.14159256…
3. M = E – e sinE.
4. E’ = M.
5. E” = M + (180°/π)e sinE’
6. r = a(1 – e cos E)

#### Do planets have a size limit?

A planet can be no bigger than about 10 times the mass of Jupiter, an astrophysicist has concluded. You can know a planet not just by its size, but also by the company it keeps: Giant planets are almost always found orbiting stars that are metal-rich, whereas brown dwarfs aren’t so discriminating.

How big are the planets in our Solar System?

Background Information Our solar system includes the sun and eight planets that orbit around the sun. The smaller, inner planets include Mercury, Venus, Earth, and Mars. The inner planets are rocky and have diameters of less than 13,000 kilometers.

How to study the size and distance of planets?

Make sure students understand that the distances between the planets are very large compared to the sizes of each planet. This makes it extremely difficult to create an exact scale of our solar system, so this activity will focus on the distance comparison. 5. Have groups create models of relative planetary distances.

## How are orbits of planets related to the size of the Sun?

They describe how (1) planets move in elliptical orbits with the Sun as a focus, (2) a planet covers the same area of space in the same amount of time no matter where it is in its orbit, and (3) a planet’s orbital period is proportional to the size of its orbit (its semi-major axis).

How big are the outer planets compared to the inner planets?

The inner planets are rocky and have diameters of less than 13,000 kilometers. The outer planets include Jupiter, Saturn, Uranus, and Neptune. The outer planets are called gas giants and have a diameter of greater than 48,000 kilometers. Pluto, which used to be considered the ninth planet,…