Is Pluto a planet?

Pluto is officially no longer classed as a planet, and here's why. The International Astronomical Union defined three rules in 2005 that a celestial body (an object observable within space) must follow to be classed as a planet:

1. The planet must orbit the sun.
2. The planet must be large enough that its gravity can smooth it into a nice spherical shape.
3. It must have cleared up the surrounding objects around it.
Pluto fails number three as it simply isn't massive enough to pull the surrounding objects into it's orbit. This is really hard for Pluto as it lives in the Kuiper Belt, a belt of other large rocky objects.
Fortunately for Pluto it matches the first two rules, so it can be classed as a dwarf planet instead!

Answered by Connor G. Physics tutor

2381 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

What is the angular velocity of a car wheel which diameter is d = 15 mm if the car velocity is of 120 km/h?


How would you integrate ln(x)


A ball is thrown up with an initial velocity of 8 m/s and initial height of 1.5m above the ground. Calculate the maximum height the ball reaches and the time it takes to get there.


A small ball is projected with speed 15 m/s at an angle of 60 degrees above the horizontal. Find the distance from the point of projection of the ball at the instant when it is travelling horizontally.


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2024

Terms & Conditions|Privacy Policy