Skip to playerSkip to main contentSkip to footer
DW (English)
  • 8/27/2024
Our Solar System has eight planets, and each has a year of a different length. That has to do with their distance from the sun and how quickly they orbit our star.
Transcript
00:00Why is the length of a year different on every planet?
00:10Eight planets orbit our sun, and they do so in more or less elliptical orbits.
00:17Most places on Earth we experience a year through the course of the seasons.
00:22Only around the equator does weather remain largely the same all year round.
00:29In astronomical terms, a year is the period of time it takes for a planet to complete
00:34a single orbit around the sun.
00:36On Earth, that's 365 terrestrial days.
00:40This has to do with our distance from the sun.
00:43It's so far away that our planet has to travel 940 million kilometers to complete one orbit.
00:53Vast in size compared to the planets, the sun exerts enormous gravity.
00:58To remain in a stable orbit, the Earth must circle it at a very specific speed, 30 kilometers
01:05per second.
01:09If our planet moved any slower, it would get closer to our star.
01:17If it went faster, it would drift further and further away.
01:24The duration of a year therefore depends on how far away from the sun a planet orbits,
01:30as well as its speed.
01:32The closest of the eight to the sun is Mercury.
01:36Its orbit is much smaller than that of Earth's.
01:39But because it's so close, the effects of the sun's gravity are greater there.
01:45Mercury must orbit the sun faster to stay on track.
01:49It therefore covers less distance at a higher speed.
01:52A year on Mercury only lasts 88 Earth days.
01:58The farther away a planet is from the sun, the longer its orbit and the slower its speed.
02:04It might sound hard to believe, but a year on the outermost planet, Neptune, lasts for
02:10almost 165 of our years on Earth.

Recommended

1:00
Up next
Kepler Orrery IV
Tom's Hardware
12/2/2015
3:07
What is a leap year and why do they happen?
Australian Community Media
2/20/2024
1:16
Does The Discovery Of This Planet Break Our Theory of Planet Formation?
Amaze Lab
2/6/2025
1:16
Astronomers Discover Another Planet that Breaks Our Planet Formation Theory
Amaze Lab
8/16/2023
1:15
Astronomers Finally Find Two Planets Sharing the Same Orbit After 20 Years of Searching
Amaze Lab
7/20/2023
6:31
What If Earth Was Bigger Than The Sun?
Unveiled
6/18/2019
1:16
Does This Planet Break The Theory of Planet Formation That Scientists Have Relied On
Amaze Lab
7/1/2025
1:10
The Search For The Real Planet X
Popular Science
1/19/2016
1:12
This is the Moment a Star Expands to Eat One of its Orbiting Planets
Amaze Lab
9/30/2024
1:08
Scientists discover new planet more than 600 light years away
TomoNews US
6/12/2018
4:21
What If a New Planet Formed in the Solar System?
WHAT IF
2/19/2021
1:20
Does Our Solar System Actually Have 9 Planets Even After Pluto Was Eliminated?
Amaze Lab
2/10/2025
1:09
Astronomers Might Finally Know Where to Look for the 9th Planet
Amaze Lab
9/1/2021
1:04
Do the Planets in Our Solar System Ever Perfectly Align?
Amaze Lab
10/10/2019
1:00
NASA discovers eighth planet orbiting distant star
AccuWeather
12/15/2017
1:13
Did You Know That 1-in-12 Stars Have Actually Eaten a Planet in Their System?
Amaze Lab
5/28/2025
5:12
What If Another Sun Entered Our Solar System?
WHAT IF
11/9/2022
1:13
Stellar Survey Finds 1-in-12 Stars Have Eaten a Planet in Their System
Amaze Lab
3/21/2024
1:20
Astronomers Say They’ve Found the ‘Strongest Statistical Evidence Yet’ for Ninth Planet in the Solar System
Amaze Lab
4/29/2024
0:45
Earth-like planet found orbiting nearby star
ODN
8/24/2016
4:44
Finding Our True Ninth Planet
Popular Science
3/20/2017
1:07
Distances between the planets and the Sun
Videoo.tv (English)
2/18/2021
1:29
Astronomers Find First Evidence of Tidal Locking Outside Our Solar System
Amaze Lab
4/10/2024
1:42
Rubio and Lavrov arrive in KL for Asean Foreign Ministers meeting
The Star
today
1:17
Cyberjaya student murder: Two suspects brought to court to face charges
The Star
today