Chapter 3: Problem 44
Suppose a new dwarf planet is discovered orbiting the Sun with a semimajor axis of 50 AU. What would be the orbital period of this new dwarf planet?
Short Answer
Expert verified
The orbital period is about 353.55 years.
Step by step solution
01
Identify Kepler's Third Law
Kepler's Third Law states that the square of the orbital period (P) of a planet is directly proportional to the cube of the semimajor axis (a) of its orbit: \[ P^2 = a^3 \] where P is in years and a is in astronomical units (AU).
02
Insert the Given Semimajor Axis
The exercise provides the semimajor axis (a) as 50 AU. Substitute this value into Kepler's Third Law: \[ P^2 = 50^3 \]
03
Calculate the Cube of the Semimajor Axis
Compute the value of 50 cubed: \[ 50^3 = 50 \times 50 \times 50 = 125000 \] Therefore, \[ P^2 = 125000 \]
04
Solve for the Orbital Period (P)
To find the orbital period (P), take the square root of both sides of the equation: \[ P = \sqrt{125000} \] Approximately, \[ P = 353.55 \] years.
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with Vaia!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Orbital Period
The orbital period of a celestial object, such as a planet or a dwarf planet, is the time it takes to complete one full orbit around its parent star, which, in our case, is the Sun. This is a crucial concept in astronomy, as it helps to understand the dynamics of planetary systems. The orbital period can vary greatly depending on the distance from the Sun and follows a predictable pattern described by Kepler's Third Law.
In our exercise, we found the orbital period of a new dwarf planet using the law. It's essential to note that the further a planet is from the Sun, the longer its orbital period will be. For instance:
* Earth takes 1 year to orbit the Sun
* Jupiter takes about 12 years
For our new dwarf planet with a more distant orbit, it takes approximately 353.55 years!
In our exercise, we found the orbital period of a new dwarf planet using the law. It's essential to note that the further a planet is from the Sun, the longer its orbital period will be. For instance:
* Earth takes 1 year to orbit the Sun
* Jupiter takes about 12 years
For our new dwarf planet with a more distant orbit, it takes approximately 353.55 years!
Semimajor Axis
The semimajor axis is one of the most important parameters in describing the shape and size of an orbit. It is essentially half of the longest diameter of an elliptical orbit. For objects orbiting the Sun, such as planets and dwarf planets, the semimajor axis determines the average distance from the Sun.
In the given exercise, the new dwarf planet has a semimajor axis of 50 AU. This means its average distance from the Sun is 50 times the distance between the Earth and the Sun. The size of the semimajor axis directly affects the planet's orbital period. Using Kepler's Third Law, we can relate the length of the semimajor axis to the time it takes for the dwarf planet to make one complete orbit around the Sun.
In the given exercise, the new dwarf planet has a semimajor axis of 50 AU. This means its average distance from the Sun is 50 times the distance between the Earth and the Sun. The size of the semimajor axis directly affects the planet's orbital period. Using Kepler's Third Law, we can relate the length of the semimajor axis to the time it takes for the dwarf planet to make one complete orbit around the Sun.
Dwarf Planet
A dwarf planet is a celestial body that shares many characteristics with planets, but does not fit all the criteria to be classified as one. According to the International Astronomical Union, a dwarf planet:
* Orbits the Sun
* Has sufficient mass for its self-gravity to overcome rigid body forces, meaning it has a nearly round shape
* Has not cleared its neighboring region of other objects
In our exercise, we are dealing with a newly discovered dwarf planet. While it orbits the Sun and likely has a nearly round shape, it has not cleared its orbit of other debris and objects. This aspect separates it from being classified as a full-fledged planet like Earth or Jupiter.
* Orbits the Sun
* Has sufficient mass for its self-gravity to overcome rigid body forces, meaning it has a nearly round shape
* Has not cleared its neighboring region of other objects
In our exercise, we are dealing with a newly discovered dwarf planet. While it orbits the Sun and likely has a nearly round shape, it has not cleared its orbit of other debris and objects. This aspect separates it from being classified as a full-fledged planet like Earth or Jupiter.
Astronomical Units
An astronomical unit (AU) is a standard unit of measurement used by astronomers to describe distances within our solar system. One astronomical unit is equal to the average distance from the Earth to the Sun, which is about 93 million miles or 150 million kilometers.
AU make it simpler to handle and compare vast distances between objects in the solar system:
* Earth's distance to the Sun: 1 AU
* Jupiter's distance to the Sun: approx. 5.2 AU
In our exercise, the semimajor axis of the dwarf planet's orbit is given as 50 AU, meaning this dwarf planet is 50 times farther from the Sun than the Earth is. Using AU allows us to quickly grasp and communicate these immense distances without resorting to very large numbers.
AU make it simpler to handle and compare vast distances between objects in the solar system:
* Earth's distance to the Sun: 1 AU
* Jupiter's distance to the Sun: approx. 5.2 AU
In our exercise, the semimajor axis of the dwarf planet's orbit is given as 50 AU, meaning this dwarf planet is 50 times farther from the Sun than the Earth is. Using AU allows us to quickly grasp and communicate these immense distances without resorting to very large numbers.