Hodgepodge

Planet Orbit

Orbit size is the average distance from an object to the Sun. For the major planets in our Solar System the orbit sizes are:

Planet	Orbit Size (au)
Mercury	0.4
Venus	0.7
Earth	1.0
Mars	1.5
Jupiter	5.2
Saturn	9.5
Uranus	19.2
Neptune	30.1

Astronomical Unit (AU)

The astronomical unit (AU) is a unit of length defined to be exactly equal to 149,597,870,691 meters (92,960,000 miles). Historically, the astronomical unit was conceived as the average Earth-Sun distance (the average of Earth's aphelion and perihelion), before its modern redefinition in 2012.

The astronomical unit is used primarily for measuring distances within the Solar System or around other stars. It is also a fundamental component in the definition of another unit of astronomical length, the parsec. One AU is equivalent to 499 light-seconds to within 10 parts per million.

From: Wikipedia

Planet Diameter

Planet	Diameter	Orbit	Day
Mercury	3,031 miles (4,878 km)	88 Earth days	58.6 Earth days
Venus	7,521 miles (12,104 km)	225 Earth days	243 Earth days
Earth	7,926 miles (12,760 km)	365.24 days	23 hours, 56 minutes
Mars	4,217 miles (6,787 km)	686.93 Earth days	24 hours, 37 minutes
Jupiter	86,881 miles (139,822 km)	11.9 Earth years	9.8 Earth hours
Saturn	74,900 miles (120,500 km)	29.4 Earth years	10 hours, 34 minutes
Uranus	31,763 miles (51,120 km)	84 Earth years	17 hours, 14 minutes
Neptune	30,775 miles (49,530 km)	165 Earth years	15 hours, 57 minutes

From: Space.com

The Sun

The sun is about 864,000 miles (1,392,000 km) in diameter.

It is located about 93 million miles (150 million kilometers) from Earth and orbits the Galactic Center at a distance of 24,000 to 28,000 light-years.

The sun's mass is about 333,000 times the mass of Earth, making up about 99.86% of the total mass of the Solar System.

The Sun rotates on its axis once in about 27 days. At it's equator it is rotating approximately 1.241 miles per second.

Wikipedia: Sun.

Pluto

Pluto is about 1,477 miles (2,377 kilometers) in diameter.

Pluto's day is 6.4 Earth days.

Pluto is, on average, 39.5 astronomical units (AU) away from the Sun.

Pluto has a highly elliptical orbit ranging from around 29.7 AU at its closest point (perihelion) to 49.3 AU at its furthest point (aphelion).

Wikipedia: Pluto.

Moon

The Moon is about 2,159 miles (3,475 kilometers) in diameter.

The Moon orbits Earth completes one revolution relative to the Vernal Equinox and the stars in about 27.32 days (a tropical month and sidereal month) and one revolution relative to the Sun in about 29.53 days (a synodic month).

Note: See "sidereal month" and "synodic month".

Wikipedia: Orbit of The Moon.

What Is This Code Telling Us?

#!/usr/bin/python3 # =================================================================== # solar system (sun + first 4 planets + Neptune) # =================================================================== au_distance_meters = 149_597_870_691 max_radius_pixels = 200 sun_diameter_meters = 1_392_700_000 # ---- convert Sun's raidus to AU sun_radius_meters = sun_diameter_meters/2.0 sun_radius_au = sun_radius_meters / au_distance_meters # ---- calculate pixels per AU based on # ---- Neptune's orbit (AU) = max_radius_pixels pixels_per_au = max_radius_pixels / 30.1 # ---- display raidus in pixels print() print('Orbit (Circle) Raidus in Pixels') print(f'Sun {sun_radius_au*pixels_per_au:.3f} pixels ' +\ f'(au={sun_radius_au:.3f})') print(f'Mecury {0.4*pixels_per_au:.3f} pixels') print(f'Venus {0.7*pixels_per_au:.3f} pixels') print(f'Earth {1.0*pixels_per_au:.3f} pixels') print(f'Mars {1.5*pixels_per_au:.3f} pixels') print(f'Neptune {30.1*pixels_per_au:.3f} pixels') print()

Question

Measurements may vary depending on the source. What is the difference between accuracy and precision?