There are eight planets in our solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

Quick Scoop: How Many Planets?

If you’re asking “how many planets are there?” in the everyday, textbook sense, the accepted answer today is eight.

These are the worlds that officially count as “planets” under the definition adopted by the International Astronomical Union (IAU) in 2006.

The Official Eight

The planets, in order from the Sun, are:

  1. Mercury
  2. Venus
  3. Earth
  4. Mars
  5. Jupiter
  6. Saturn
  7. Uranus
  8. Neptune

Astronomers group them like this:

  • Inner terrestrial planets (rocky): Mercury, Venus, Earth, Mars
  • Outer giant planets:
    • Gas giants: Jupiter, Saturn
    • Ice giants: Uranus, Neptune

What About Pluto?

For much of the 20th century, people were taught that there were nine planets, including Pluto.

In 2006, the IAU refined the definition of a planet and reclassified Pluto as a dwarf planet because it has not “cleared its orbit” of other debris.

Under the IAU definition, a planet must:

  1. Orbit the Sun.
  2. Be massive enough for its gravity to pull it into a nearly round shape.
  3. Have cleared its orbit of other objects.

Pluto passes the first two tests but fails the third, sharing its region with many Kuiper Belt objects.

Is the Answer Always “Eight”?

Here’s where the forum debates and “latest news” twists come in:

  • Many scientists and educators:
    • Stick with eight planets, following the IAU definition.
  • Pluto fans and some astronomers:
    • Still like to talk about “nine planets,” counting Pluto for historical and cultural reasons.
  • Dwarf planets and beyond:
    • If you relax the definition and count every roughly round body orbiting the Sun (including dwarf planets like Ceres, Pluto, Eris, Haumea, Makemake), you quickly get to the hundreds or even thousands of “planet-like” worlds.

Some recent scientific discussions even consider a possible undiscovered “Planet Nine” far beyond Neptune, which would change the tally again if confirmed.

So in everyday use: 8 planets.
In looser or nostalgic use: sometimes 9.
In very broad, technical discussions: potentially hundreds or thousands of round worlds in our solar system.

A Tiny Story To Remember It

Imagine a teacher in the 1990s, confidently writing nine planet names across the board.
Fast-forward to a classroom today: the same teacher pauses at Pluto, then explains to confused students that science updated its rules , not its affection—Pluto didn’t “shrink,” we just got better at categorizing a crowded solar system.

And if you want a quick memory hook, one popular English mnemonic for the eight is:

“My very excellent mother just served us noodles”
Each first letter lines up with the planets from Mercury to Neptune.

TL;DR: In modern astronomy, our solar system has 8 official planets , with Pluto and several others classified as dwarf planets rather than full planets.