What Actually Happens If You Try To Land On Earth 2.0 (Kepler-452b) — Transcript

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1. 0:00Your ship drops out of cruise, and for
2. 0:02the first time in a very long time,
3. 0:04there is a sun in the window. That is
4. 0:06the unsettling part. It looks right.
5. 0:08Same yellow-white glare. Roughly the
6. 0:10same size. If someone told you this was
7. 0:13home, you would almost believe them.
8. 0:15Mostly because you want to.
9. 0:17It is not home. That star is Kepler-452,
10. 0:21and it sits somewhere between 1,400 and
11. 0:231,800 light-years from Earth. Either
12. 0:25way, the light leaving this star right
13. 0:27now will reach Earth long after everyone
14. 0:29you know has stopped existing. How you
15. 0:31got here does not matter. With the
16. 0:33fastest probes humans have ever
17. 0:35launched, this trip would take millions
18. 0:36of years. You did it anyway. The ship is
19. 0:39tired, you are tired, and somewhere
20. 0:41ahead of you is the planet NASA, once
21. 0:44introduced to the world as Earth's
22. 0:45bigger, older cousin. Kepler-452b.
23. 0:49In 2015, it was everywhere. A world
24. 0:52roughly 1 and 1/2 times wider than
25. 0:54Earth, circling a sun-like star at
26. 0:57almost exactly the distance Earth
27. 0:58circles ours. Its year lasts about 385
28. 1:02days. So, if you ever live here, your
29. 1:04birthday shows up roughly 3 weeks late.
30. 1:07Every year. Forever. It orbits inside
31. 1:10the habitable zone, the band around a
32. 1:12star where liquid water could exist on a
33. 1:14surface. That phrase did a lot of heavy
34. 1:16lifting in the headlines. It does not
35. 1:18mean habitable. It means not obviously
36. 1:21ruled out. As property listings go, that
37. 1:23is not a glowing review.
38. 1:25You turn the ship toward it and wait. At
39. 1:27first, it is a point of light, then a
40. 1:29tiny pale disk. Then you realize
41. 1:31something alarming. Nobody has ever seen
42. 1:34this planet. Not really. The Kepler
43. 1:36space telescope never photographed it.
44. 1:39What Kepler saw was the star dimming
45. 1:41very slightly a handful of times as
46. 1:43something small passed in front of it.
47. 1:45Every headline, every artist's
48. 1:47impression, every hopeful article about
49. 1:49Earth 2.0 came from a few tiny dips in
50. 1:52starlight. From those dips, astronomers
51. 1:55worked out the planet's size and the
52. 1:56length of its year.
53. 1:58Almost everything else was a guess. Its
54. 2:00mass unknown, its air unknown, whether
55. 2:04it has a solid surface at all, also
56. 2:06unknown.
57. 2:07You were about to be the first to find
58. 2:09out, which is exciting right up until
59. 2:11you remember that you were also the test
60. 2:13subject.
61. 2:15You fire the engines and slow down until
62. 2:16the planet catches you in orbit. Now,
63. 2:18the most important instrument on your
64. 2:20ship is not a camera or a spectrometer,
65. 2:22it is a clock.
66. 2:24Because the time it takes you to loop
67. 2:25around the planet depends on how hard
68. 2:27the planet is pulling.
69. 2:28Time one orbit and you can weigh an
70. 2:30entire world. Something no telescope on
71. 2:33Earth managed, you do with a stopwatch.
72. 2:35And the weight decides everything
73. 2:37because planets this size go two very
74. 2:39different ways.
75. 2:40Some are rocky, bigger, heavier versions
76. 2:42of Earth with ground you can stand on.
77. 2:45Others are puffy, rock buried deep under
78. 2:47a thick blanket of hydrogen and helium
79. 2:49gas. On a world like that, you do not
80. 2:51land. You descend through air that gets
81. 2:54thicker and hotter and heavier until the
82. 2:57pressure crushes your ship long before
83. 2:59anything resembling a floor arrives.
84. 3:01You just keep sinking until you stop
85. 3:03being a spaceship and start being a
86. 3:05small, very expensive pebble.
87. 3:07Kepler 452b sits right around the size
88. 3:10where planets tend to flip from one kind
89. 3:12to the other. Your landing plan has been
90. 3:14a coin toss for the entire trip.
91. 3:16The orbit timer finishes. The number
92. 3:18comes back.
93. 3:19In this version of events, the planet is
94. 3:21heavy, roughly five times the mass of
95. 3:23Earth, dense enough to be rock. There is
96. 3:26ground down
97. 3:27The bad news arrives with it.
98. 3:29A planet five times heavier than Earth,
99. 3:32but only about 1 and 1/2 times wider,
100. 3:34pulls on you a lot harder. At the
101. 3:36surface, you should feel somewhere
102. 3:37around twice your normal weight. You
103. 3:39pull up your lander specifications. They
104. 3:41were drawn up back on Earth by engineers
105. 3:43who did not know the planet's mass. They
106. 3:46made a reasonable guess. You are about
107. 3:48to learn how reasonable.
108. 3:49You undock and start falling.
109. 3:52On Earth, a capsule coming home from
110. 3:54orbit hits the air at nearly 8 km per
111. 3:56second. Here, the stronger gravity means
112. 3:58everything in orbit moves faster. You
113. 4:01hit the top of the atmosphere far
114. 4:02quicker than any astronaut ever has, and
115. 4:04the heating rises steeply with speed.
116. 4:07The heat shield glows, then it glows
117. 4:09harder. The window turns orange, then
118. 4:11white. Your capsule shakes like it has
119. 4:14opinions about this.
120. 4:16Heavier planets can hold on to more air
121. 4:18than Earth does, and this one seems to
122. 4:20have kept plenty. The atmosphere grabs
123. 4:22you earlier and harder than expected.
124. 4:24The deceleration presses you deep into
125. 4:26your seat, and underneath all of that,
126. 4:29the planet itself is pulling twice as
127. 4:30hard. For a while, breathing feels like
128. 4:33a task you have to schedule.
129. 4:35Then the glow fades.
130. 4:37Thick gray cloud whips past the window.
131. 4:39The parachutes deploy.
132. 4:41For once, the planet is on your side.
133. 4:44Dense air is wonderful for parachutes.
134. 4:46Unfortunately, gravity is also pulling
135. 4:48twice as hard. So, the air and the
136. 4:50planet spend the rest of your descent
137. 4:52arguing about you.
138. 4:54The clouds break.
139. 4:55Below you, there is dark water, a rocky
140. 4:58coastline, and a sky full of pale haze.
141. 5:01The thrusters fire for the final few
142. 5:03meters.
143. 5:04You hit the ground harder than any
144. 5:05simulation suggested, but the landing
145. 5:07legs hold. Everything goes quiet. You
146. 5:10have landed on Kepler-452b,
147. 5:13a planet so far away that the light you
148. 5:15first spotted it by left its star before
149. 5:17anyone on Earth had invented the
150. 5:19printing press.
151. 5:21If you're enjoying this video, please
152. 5:22hit the subscribe button. It genuinely
153. 5:24helps keep the channel alive. Now, you
154. 5:26try to stand up. This is where the
155. 5:28planet introduces itself properly.
156. 5:30Everything weighs about twice as much.
157. 5:32Your arms, your head,
158. 5:34your suit, which on Earth was already
159. 5:36heavy, and which on Kepler-452b
160. 5:39feels like carrying a second person who
161. 5:40refuses to walk.
162. 5:42You push yourself up out of the seat,
163. 5:44and your legs start to shake.
164. 5:46Your heart has a new job, too. On Earth,
165. 5:48it pushes blood up to your brain against
166. 5:50one gravity.
167. 5:52Here, it is pushing against roughly two.
168. 5:54Stand up too fast, and blood can pool in
169. 5:56your legs, your vision can gray out at
170. 5:58the edges, and the cabin starts tilting
171. 6:01in a way the cabin is definitely not
172. 6:02tilting.
173. 6:03So, you stand up slowly, very slowly,
174. 6:06like someone getting out of a bath after
175. 6:08a long day, except the bath is a planet.
176. 6:11You open the hatch and step outside. The
177. 6:14first thing you notice is the heat.
178. 6:16Kepler-452b receives roughly 10% more
179. 6:19energy from its star than Earth gets
180. 6:20from the Sun. That does not sound like
181. 6:22much. Climate disagrees.
182. 6:25A small extra push of energy can tip a
183. 6:27planet with oceans into a warmer,
184. 6:29wetter, and much less comfortable state.
185. 6:31Your suit's cooling system, which was
186. 6:33designed to keep you comfortable, is now
187. 6:35mostly concerned with keeping you alive.
188. 6:37You take a step and immediately
189. 6:39understand that walking is going to be a
190. 6:41project.
191. 6:42Every step lifts double the weight. Your
192. 6:45thighs burn after a few dozen meters.
193. 6:47You drop a sample container and it does
194. 6:49not drift down the way things floated on
195. 6:51the moon in old footage. It slams into
196. 6:53the ground almost instantly because here
197. 6:56falling happens fast. That includes you.
198. 6:59Trip on a rock and you hit the ground
199. 7:01sooner and harder than you would back
200. 7:02home. A stumble you would laugh off on
201. 7:04Earth could break a wrist here. So, you
202. 7:06walk like the ground is made of glass
203. 7:08and the planet watches you do it. You
204. 7:10reach the shoreline and kneel next to
205. 7:12the water.
206. 7:13And the headlines start to look very
207. 7:14different. Its star is old, roughly 1
208. 7:17and 1/2 billion years older than the
209. 7:19Sun, and stars like this slowly get
210. 7:21brighter as they age. The Sun is doing
211. 7:23it, too. You just never noticed because
212. 7:26it takes hundreds of millions of years.
213. 7:28That slow brightening is a problem for
214. 7:30any planet with oceans. More heat means
215. 7:33more water evaporates. Water vapor traps
216. 7:35heat. More trapped heat means even more
217. 7:37evaporation. If that loop runs away, the
218. 7:40oceans can eventually be driven off into
219. 7:42the sky and the planet ends up as a
220. 7:44scorching greenhouse.
221. 7:46When NASA announced Kepler-452b,
222. 7:49the scientists behind the discovery
223. 7:50pointed this out themselves. This planet
224. 7:53might be going through right now what
225. 7:54Earth will go through more than a
226. 7:55billion years from now. So, you are not
227. 7:57standing on Earth's twin.
228. 7:59You might be standing on Earth's future.
229. 8:02Whether this world is still comfortably
230. 8:03wet or already sliding toward that
231. 8:05runaway greenhouse is not something you
232. 8:07can tell from one beach in one
233. 8:09afternoon. But the direction of travel
234. 8:11is not encouraging.
235. 8:13And then there is the other question
236. 8:14everyone asked back in 2015. Is anything
237. 8:17alive here? This star system is older
238. 8:20than ours. If life ever started on
239. 8:22Kepler-452b,
240. 8:24it could have had a head start of more
241. 8:25than a billion years on life back home.
242. 8:28That is either the most exciting fact in
243. 8:30the universe or a deeply concerning one,
244. 8:32depending on what that life decided to
245. 8:34do with its spare time.
246. 8:36You scan the shoreline. Rocks, water,
247. 8:39haze, nothing waves back. That does not
248. 8:42mean nothing is here. If an alien
249. 8:44dropped onto a random spot on Earth, it
250. 8:46would most likely splash into an empty
251. 8:48stretch of ocean and decide the planet
252. 8:50was boring. Searching a whole world for
253. 8:52life takes years, not one walk on a
254. 8:54beach. And years, it turns out, are
255. 8:56exactly what you have because you are
256. 8:59not leaving anytime soon.
257. 9:01Remember those engineers back home
258. 9:02guessing at the planet's mass? This is
259. 9:04where the guess gets expensive. To reach
260. 9:07orbit from Earth, rockets need around 8
261. 9:09km/s plus extra to fight the air and the
262. 9:12pull of gravity on the way up.
263. 9:14Kepler-452b's stronger pull pushes that
264. 9:17requirement much higher.
265. 9:19And rockets do not scale nicely. To go
266. 9:21faster, you need more fuel. But fuel is
267. 9:23heavy, so you need more fuel to lift
268. 9:26that fuel, which needs more fuel to lift
269. 9:28that. On a heavy enough planet, the
270. 9:30rocket you need to escape stops being
271. 9:32twice as big and becomes many times
272. 9:34bigger.
273. 9:35You look at your ascent stage. It was
274. 9:37built for a lighter planet. It was built
275. 9:39for a guess.
276. 9:41It turns out landing on Kepler-452b was
277. 9:43the easy part. Gravity was delighted to
278. 9:45help with that. It is much less
279. 9:47interested in letting you go.
280. 9:49So you do the only thing you can still
281. 9:51do. You call home.
282. 9:53You point your antenna at an
283. 9:54empty-looking patch of sky. Your sun is
284. 9:57in there somewhere.
285. 9:58From this far away, it is far too faint
286. 10:00to see with your own eyes. You send the
287. 10:03message anyway. I made it.
288. 10:05The planet is real. I cannot leave. The
289. 10:08message travels at the speed of light,
290. 10:10and it will still take somewhere between
291. 10:1114 and 18 centuries to arrive. When it
292. 10:14gets there, the people who built your
293. 10:16ship will be long gone. So will their
294. 10:18grandchildren. Whoever reads it will be
295. 10:20living in a world you cannot picture,
296. 10:22receiving news from someone who stopped
297. 10:24existing a very long time ago. Your
298. 10:26supplies will last as long as supplies
299. 10:28last. After that, Kepler-452b
300. 10:31gets either its first grave or its first
301. 10:33permanent resident. From the planet's
302. 10:35point of view, there is not much
303. 10:37difference. And here is the final irony.
304. 10:40Back on Earth, a few years after the big
305. 10:42announcement, astronomers went back
306. 10:44through Kepler's data. The signal from
307. 10:46Kepler-452b was faint, sitting
308. 10:48uncomfortably close to the telescope's
309. 10:50background noise. Some researchers
310. 10:52argued that with the data available,
311. 10:55nobody could confidently confirm the
312. 10:56planet existed at all. It might be real,
313. 10:59it might be a statistical ghost. So the
314. 11:02famous Earth 2.0, the planet on the
315. 11:04posters and in the headlines, quietly
316. 11:07spent years as a scientific maybe.
317. 11:09Which means the message drifting away
318. 11:11from you right now will be the first
319. 11:12real proof that it exists. You crossed
320. 11:15more than a thousand light-years to
321. 11:16stand on a world that might not have
322. 11:17been there. It is. You are standing on
323. 11:20it. Heavy, hot, exhausted, and
324. 11:23permanently stuck.
325. 11:24Your suit beeps. The haze shifts and for
326. 11:27a moment you can see the star again,
327. 11:29high overhead, almost exactly like the
328. 11:31sun. Just a little older, just a little
329. 11:34brighter, and getting brighter every
330. 11:36year. Exactly like yours will.