Why Is Jupiter’s Moon Ganymede Teaching the Planets?! | Planet School

[00:00:00]It was another busy day at Planet School.

[00:00:03]The planets were waiting in class, ready for another day of learning.

[00:00:08]Well… most of them were ready.

[00:00:10]I’m ready! I’ve been ready since yesterday!

[00:00:14]Wait, if we are all here dudes, who is the teacher today?

[00:00:20]Good morning, planets.

[00:00:23]Are you teaching today, Ganymede?

[00:00:26]Yes.

[00:00:28]A moon? Teaching me? What qualifies you, Ganymoon?

[00:00:35]Ganymede. Largest moon in the Solar System. Jupiter’s moon.

[00:00:41]Professional door watcher. Occasional sandwich protector.

[00:00:45]He is very good at protecting sandwiches.

[00:00:50]Today’s lesson is called… THE HISTORY OF LOOKING AT SPACE I looked at space this morning. It was dark. Lesson over!

[00:01:02]A long time ago, people looked at space with the first space tool ever.

[00:01:07]A super laser?

[00:01:09]A space guitar?

[00:01:11]A very, very tall ladder?

[00:01:14]Their eyes.

[00:01:16]Simple. But useful.

[00:01:18]People looked up and saw the Sun, the Moon, the stars… and some bright dots that moved differently from the stars.

[00:01:27]Excuse me. Bright dot?

[00:01:30]Yes, Venus. You were one of the bright dots.

[00:01:34]I am not a bright dot. I am fabulous.

[00:01:39]Five planets are bright enough to see without a telescope: Mercury, Venus, Mars, Jupiter, and Saturn.

[00:01:47]Yes! I’m visible! Tiny but visible!

[00:01:52]Obviously I’m visible. My rings demand it!

[00:01:57]Wait! I’m not on that list?

[00:02:01]Uranus can sometimes be just about seen in very dark skies.

[00:02:06]But ancient people didn’t recognise it as a planet.

[00:02:10]Typical!

[00:02:14]With telescopes, planets were no longer just bright dots.

[00:02:19]They saw Jupiter had moons.

[00:02:21]Ahem, impressive moons!

[00:02:24]Including me.

[00:02:27]They saw craters on the Moon, phases of Venus, and more and more details that human eyes could not see alone.

[00:02:34]My phases are all excellent.

[00:02:37]Scientists collect clues. A bright dot.

[00:02:40]A shadow. A tiny wobble. Then they ask: what does this clue mean?

[00:02:46]Usually it means trouble.

[00:02:49]Then humans built spacecraft.

[00:02:52]Spacecraft flew past or orbited planets. Some landed on worlds.

[00:02:57]They came all the way to visit us.

[00:03:00]Very rude. No appointment.

[00:03:03]So first people looked with eyes… Then telescopes… Then spacecraft and robots… Then computers and cameras… Exactly. And maths. Lots of maths.

[00:03:18]Boring!

[00:03:20]Like space detectives.

[00:03:23]Correct.

[00:03:24]My eyes tell me it’s lunchtime.

[00:03:31]I like sweeping.

[00:03:34]That’s… nice.

[00:03:36]Sweeping is peaceful.

[00:03:38]Time to sweep.

[00:03:45]"Flying! Get on board!"

[00:03:53]"We're smiling" "On top of the world!"

[00:04:03]"Flying! Get on board" In the afternoon, Ganymede took the class on a special Work Experience trip.

[00:04:27]Welcome to Jupiter’s Kitchen!

[00:04:30]Today for Work Experience, you are learning security.

[00:04:35]Security? Like stopping danger?

[00:04:38]Yes. A good guard watches carefully, asks questions, and decides who should come in.

[00:04:46]Like space detective work again.

[00:04:48]Exactly.

[00:04:50]Can my security method be “say no to everyone”?

[00:04:55]No... Terrible system!

[00:04:59]First guard: Mercury.

[00:05:02]Nobody gets past me!

[00:05:05]Excuse me, I’m on the VIP list.

[00:05:09]Name?

[00:05:10]Venus.

[00:05:12]Reason for entry?

[00:05:14]I’m fabulous.

[00:05:16]Checks out! You may enter!

[00:05:19]Mercury, that is not enough information.

[00:05:22]But she said it very confidently.

[00:05:25]Thank you, thank you!

[00:05:28]Next guard: Mars.

[00:05:32]Name?

[00:05:34]Earth.

[00:05:35]You don’t look like Earth.

[00:05:37]It is me If you’re Earth – tell me a joke.

[00:05:43]Why did the planet start a band?

[00:05:46]Because it had rock music!

[00:05:49]That was terrible.

[00:05:51]Exactly.

[00:05:54]Earth confirmed. You may enter.

[00:05:57]Not bad. You asked a checking question.

[00:06:01]And suffered through the answer.

[00:06:06]Final guard: Uranus.

[00:06:09]At last, Ganymoon. Someone competent.

[00:06:13]Make way, make way!

[00:06:17]No!

[00:06:19]I haven’t said anything yet.

[00:06:21]Too friendly. Suspicious.

[00:06:25]I’m only here for lunch.

[00:06:27]Classic cover story.

[00:06:30]I brought napkins.

[00:06:32]Napkins?

[00:06:34]Yes. In case Jupiter spills anything.

[00:06:38]Again... Hmm. That is sensible.

[00:06:43]Thank you.

[00:06:45]Approved. But I’m watching you!

[00:06:49]That was… somehow the best security check so far.

[00:06:54]Obviously. I suspected everyone equally.

[00:06:59]Security training complete. Snack time!

[00:07:04]And what did we learn today?

[00:07:07]Space science started with people looking up!

[00:07:10]Telescopes helped planets stop being bright dots.

[00:07:14]Spacecraft and robots sent back clues.

[00:07:17]Maths is still scary.

[00:07:20]And everyone is a suspect. Especially Neptune and her napkins.

[00:07:28]Close enough.

[00:07:35]"Flying! Get on board."