Every Type of Planet Explained.

Added: 2026-05-10

[00:00:00]Terrestrial planets, rocky, solid, and potentially lethal. Made of rock and metal with an actual surface you could stand on. These are the planets that feel the most familiar. Earth being one of them. But most terrestrial planets discovered outside our solar system orbit so close to their star that surface temperatures are high enough to melt lead on contact. ocean planets. No land, no continents, just water entirely covered by a global ocean that in some cases could be thousands of kilometers deep with no continent, no shoreline, and no bottom in sight. Kepler 22b is the most well-known candidate, 2.4 times the size of Earth, sitting right in its stars habitable zone. Near the surface, conditions might actually be survivable.

[00:00:48]But deeper down, the pressure climbs to millions of times what we experience at the bottom of Earth's deepest trench.

[00:00:55]And anything that fell in would be crushed long before it got anywhere near the bottom, if there even is one. Carbon planets, a diamond core the size of a world. In star systems where carbon outnumbers oxygen during formation, planetary interiors crystallize under extreme pressure, building a core made almost entirely of diamond, potentially hundreds of kilome thick. 55 Canankree E is the most famous example. A planet twice Earth's size with a diamondrich interior worth more than any number humans have ever used. The surface, however, sits at 2,400° C, coated in graphite and toxic carbon compounds. Gas giants, massive planets orbiting their star so closely that a full year lasts only a few Earth days, with the permanent dayside baking at over 2,000° C, while the night side sits in frozen darkness. The temperature difference between the two generates winds reaching up to 10,000 km per hour.

[00:01:56]And with no surface to land on and no atmosphere to breathe, you'd be torn apart and incinerated before you even processed what was happening. Super Earths, rocky planets up to 10 times Earth's mass, sometimes sitting in the habitable zone of their star with possible liquid water on the surface. On paper, the most promising candidates for life we've ever found. The problem is gravity. On a super Earth twice our mass, you'd weigh double what you do now. Your heart would struggle to pump blood upward, and walking would feel like permanently carrying another person on your back for the rest of your life.

[00:02:30]Long-term survival without significant biological adaptation would be almost impossible. Ice giants, frozen on the outside, very strange on the inside.

[00:02:40]With surface temperatures hovering around -200° C, these planets are hostile enough on the surface. But what makes them genuinely fascinating is what happens deeper inside where pressure becomes so extreme that water molecules are forced into a superionic state simultaneously solid and liquid and electrically conductive in a way that has absolutely no equivalent anywhere on Earth. Scientists only confirm this state existed in 2018 and still don't fully understand it. Meaning we have planets in our own solar system hiding physics we haven't figured out yet.

[00:03:17]Rogue planets, no star, no light, no destination. Planets that were ejected from their solar systems and now drift through interstellar space, completely alone at temperatures near -270° C in absolute darkness with no star to orbit and nowhere to go. Scientists estimate there could be billions of them moving through the Milky Way right now.