An astrophysicist reacts to MOONFALL | Could a white dwarf fit inside the Moon?!

In Moonfall, the Moon tumbles out of orbit due to alien intervention and chaos and destruction reign on Earth. But which parts of the movie follow actual science and which parts are definitely FICTION? I never thought I'd be calculating the mass of a white dwarf the size of the Moon, but here we are...

01:01 - Why solar eclipses are coincidences not conspiracies
02:47 - The Moon isn’t hollow
03:55 - How to change the orbit of a solar system object
05:36 - The DART mission to redirect an asteroid
06:09 - The Moon’s elliptical orbit
06:31 - The Roche limit
08:32 - Calculating the Earth-Moon Roche limit
09:14 - High tide times and the phases of the Moon
10:36 - “Gravity waves” and gravitational waves
12:27 - Moonrise and increased gravity
13:12 - The Moon has a white dwarf inside?!
15:31 - Calculating the mass of a white dwarf the size of the Moon
17:26 - Sounds like Brian Cox
17:47 - Stop destroying the Hubble Space Telescope!
18:36 - The End
19:41 - Brilliant
20:55 - Bloopers

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👩🏽‍💻 I'm Dr Becky Smethurst, an astrophysicist at University of Oxford (Christ Church). I love making videos about science with an unnatural level of enthusiasm. I like to focus on *how* we know things, not just what we know. And especially, the things we still don't know. If you've ever wondered about something in space and couldn't find an answer online - you can ask me! My day job is to do research into how supermassive black holes can affect the galaxies that they live in. In particular, I look at whether the energy output from the disk of material orbiting around a growing supermassive black hole can stop a galaxy from forming stars.

[JRainshadow]

A gravity wave that size would definitely cause a sharknado.

[SeedyJohnson]

I like how the gravity of the passing moon was enough to lift a large tree off the ground (probably around two to four tons), but not a person. Also, the moon managed to avoid destroying or disrupting any of the communication satellites, even allowing GPS to still work so that they could find the kids out in the middle of nowhere. Hollywood writers must be on the same intellectual level as habitual glue-sniffers.

[BommeltjeNL]

Thanks for reacting to Moonfall. Saw it yesterday and although I liked it as a disaster movie, my mind was going in overdrive all the time. "This is not true", "this would'nt happen that way", "that's bs" and so on and so on. Making these movies cost many millions of dollars; why don't they hire a professor or an astrophysicist like you to have a look at the script first 😂

[Tasby]

A seven year old playing with Buzz Lightyear dolls can think up more intelligent stories than Roland Emmerich.

[garymenezes]

The most difficult thing to believe was how quickly NASA got Endeavour out of a museum and flight ready

[mlungisimokhethi]

What I love about the white dwarf insode the moon part is the fact that you used Math to point out stupidity, and that's my favourite thing in the world.

[jonmaxwell]

Please keep uploading videos, I understand you are unbelievably busy with your work but your videos are so easy to watch and you get rid of all the misinformation about physics and space that is out there and your reaction videos are hilarious, keep up the good and important work for amateurs like myself and everyone else 👍👌

[AKSebi]

Please, react to "Interstellar (2014)" and "Sunshine (2007)". Would love to see your take on those films. (IMO both much better than moonfall)

[firesong]

13:18 Your disbelief at the mention of the white dwarf was hilarious.

[julianhover]

The funny thing is, that I understood every word you said. And I am a hairdresser, not an astrophysicist. So come on Emmerich. It is not that hard to do a fun movie with a little bit of accuracy 🙄

[jdmill]

Would love to see you react to Sunshine(2007). Michelle Yeoh and Cillian Murphy are excellent. From an interested layman's perspective I feel like their solution to the problem of the film is absurd, but the parts about how they travel to get to solve the problem are less absurd? I may be totally off base and they might be equally absurd though. Would love to hear your thoughts.

[chrisrehmann]

Yes, would like to see a ranking video for realistic to unrealistic. I really enjoy your reaction videos. Also like when you break down scientific papers for people who are not astrophysicist.

[thestarseeker]

Roland Emmerich’s team: how much science do you want in your new movie sir?

Roland Emmerich: No

[samvimes]

@6:10 "Can someone tell me what the hell I'm lookin' at?" "One of those bloody awful Roland Emmerich disaster movies, mate."

[Mr.JOG-]

I'm a gas station attendant. I'll make "A gas station attendant reacts to MOONFALL" soon - cause we MATTER too!

[EddieE]

i just found your channel about a month ago. You are incredible and the most "down to earth" astrophysicist on social media. Keep up all the great work!

[turbulentlobster]

Thank you for watching this so I didn't have to. The title of this one made me particularly sad because there was a 1998 novel called "Moonfall" which was both very good and was also committed to realistic physics. In this one an object from outside the solar system hit the moon hard enough to shatter it. Most of the debris stays safely in orbit but one dangerously large rock is going to impact and smart people do heroic things to save the earth. Would have made a great movie. Ah well.

[chillneophite]

Would love to see you rank sci-fi films by scientific accuracy. I would also be interested in how much you enjoyed each of the films. Would be interesting to see if you prefer the more accurate films over the less accurate films.

[ckline]

Thank you Dr. Becky for sitting through this with us. I would love to see a list of sci fi films ranked for accuracy. I think many scientifically informed laymen watch things like this, know they are wrong, but aren't sure entirely how. Thank you for helping to inform us about movies and actually astronomy.🙂

[jimbobur]

"They've harnessed the building blocks of the universe!" is now my favourite thing that's ever been said with a Lancashire accent.