2264: Satellite

Explain xkcd: It's 'cause you're dumb.
Revision as of 23:12, 5 February 2020 by 172.69.63.217 (talk) (title text)
Jump to: navigation, search
Satellite
If you're going to let it burn up, make sure it happens over the deep end of the bathtub and not any populated parts of the house!
Title text: If you're going to let it burn up, make sure it happens over the deep end of the bathtub and not any populated parts of the house!

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by a KESSLER SYNDROME. Incredibly stubby. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.

This comic humorously compares the relationship between humans and satellites to the relationship between humans and pets, with Science Girl "adopting" an "abandoned" satellite, and being lectured by her parents on how to properly discard it once it stops working, using terms and processes normally applied to satellites. ("Graveyard orbit" and "Kessler syndrome" and the bit of the sea that is the South Pacific Ocean Uninhabited Area).

A graveyard orbit is an orbit far away from operational satellites, used as a cheaper alternative to de-orbiting a satellite and letting it burn up. Typically this is achieved by briefly accelerating the satellite to send it further away from Earth; thus, Science Girl's parents refer to "boosting" the satellite into a graveyard orbit.

Kessler syndrome refers to a scenario where Earth has become surrounded by so much man-made debris that cascading collisions make space activities difficult. Apparently Science Girl has recreated this scenario before in her parents' home, requiring extensive cleanup.

The title text is more advice from Science Girl's parents. They tell her that if she is going to let her satellite reenter the atmosphere and burn up, she should do it above the bathtub. This echoes how satellites in orbit can be purposefully deorbited, and are usually planned so that any debris that isn't fully destroyed lands in the ocean and do not pose a safety risk.

Humans being orbited by space objects previously featured in 1300: Galilean Moons.

Transcript

[Science Girl is facing Cueball and Megan. A small satellite orbits her.]
Science Girl: Hey, look, I found a satellite! Can I keep it? Please?
Cueball: Sweetie, no.
Megan: Put it back where you found it.
[Only Science Girl is visible.]
Science Girl: But I think it was abandoned!
Science Girl: And it's so cute!
Science Girl: Please?
Science Girl: Pleeeease?
[The frame expands again.]
Megan: Fine. But you have to promise to boost it to a graveyard orbit when it stops working. Don't just leave it drifting around.
Science Girl: Yaaaay!
Cueball: We're serious. I am not cleaning up after Kessler syndrome again.
Megan: We couldn't use the dining room for weeks!
Science Girl: I promise, I promise.


comment.png add a comment! ⋅ comment.png add a topic (use sparingly)! ⋅ Icons-mini-action refresh blue.gif refresh comments!

Discussion

I don't care what tech hasn't been invented yet. I want one. --Blacksilver (talk) 02:28, 6 February 2020 (UTC)

Ok, then, Blacksilver: first calculate the orbital period , assuming no external gravitational sources and no atmosphere. And while you're at it, the maximum mass of the satellite before it causes the epicenter to be outside your body. But you have to take the shape of the human body into account: any deviation from equatorial orbit will probably lead to trouble.Cellocgw (talk) 14:43, 6 February 2020 (UTC)

But if we kept them around, that's less material we have to lift into orbit during Dyson sphere construction. *There are too many stars. It's been freaking me out.* (#975) 108.162.216.148 03:25, 6 February 2020 (UTC)

Am I the only one who just assumed that the characters were planet sized beings? --WhiteDragon (talk) 15:03, 6 February 2020 (UTC)

Yes ;) Elektrizikekswerk (talk) 16:39, 6 February 2020 (UTC)
I thought the same, because the sattelite was orbiting science girl. I think this is actually the first time I thought of the alternate solution first. 162.158.74.157 13:22, 10 February 2020 (UTC)


Reads ok to me. Should we take off the the header? Kev (talk) 16:31, 6 February 2020 (UTC)

Agree Elektrizikekswerk (talk) 16:39, 6 February 2020 (UTC)
What's the worst that could happen? 162.158.74.229 19:30, 6 February 2020 (UTC)
Aaand... it's gone. Elektrizikekswerk (talk) 12:44, 7 February 2020 (UTC)

I ran some preliminary calculations assuming this uses orbital mechanics that somehow ignore earth instead of some aerodynamic effects (like the flinks used in Seveneves)... first, acting out the comic I figure that the time between the beginning of the first panel and the beginning of the last panel to be about 20 seconds. Assuming the location of the satellite hasn't moved more than one orbit between each panel, our orbital period is about 20 seconds. I then measured the characters and - assuming Cueball is about 6 feet tall, the little girl is about 4 feet tall. Transposing that onto the second panel, I figure the orbit radius to be about 1.5 feet (0.4572 meters). Here I switch into metric units entirely: the orbital circumference is then 2.87 meters giving us an orbital velocity of 0.1436 m/s. Assuming the girl is an average 7 year old weighing 22.4 KG (as per This Source, and assuming that my use of the orbital equation is correct... the satellite would have a mass of 141 256 782.239 KG. Calvinrempel (talk) 00:36, 7 February 2020 (UTC)

Nah, you're doing something wrong. The orbit is independent of satellite mass ... 162.158.154.151 13:21, 7 February 2020 (UTC) <--- This is only true when the satellite's mass is insignificant relative to the planet's mass. Otherwise the epicenter ends up outside the planet's radius and we end up with either two bodies of roughly equal mass orbiting a common center or, as in this calculation, the satellite becomes the planet and the poor little girl starts orbiting the satellite Cellocgw (talk) 13:12, 10 February 2020 (UTC)

They also talk about "boosting the sattelite into a graveyeard orbit" in panel 3 which i think is the sattelite boosts from planets which would also make sense or a planet family. 162.158.214.136 21:14, 13 February 2020 (UTC)