2883: Astronaut Guests

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Astronaut Guests
They didn't bring us a gift, but considering the kinetic energy of a bottle of wine at orbital speed, that's probably for the best.
Title text: They didn't bring us a gift, but considering the kinetic energy of a bottle of wine at orbital speed, that's probably for the best.


In this comic, Cueball, Megan, Ponytail, and Hairbun can all be seen eating dinner together. Presumably, Ponytail and Hairbun were invited over for dinner, as, to impress them, Cueball misleadingly claims that they previously "had six astronauts over for dinner." Normally, this would be interpreted as the astronauts being friends with the hosts (which confers social prestige), going inside their house, and eating. As it turns out, the astronauts only briefly passed overhead while in orbit, and, by chance, this happened during dinnertime. This is a pun on the word "over", as the personnel of the International Space Station are overhead when it passes above you; yet they did not go "over to someone's house" in the sense that English speakers would usually assume.

Cueball may also be considering the property lines to extend up indefinitely (just like in "What If?" article "Star Ownership"), causing the astronauts to technically be at their house despite being hundreds of miles away, vertically.

The astronauts in question were presumably occupying the International Space Station, which has an orbital period of between 90 and 93 minutes (depending on its altitude) or 5400 to 5580 seconds.[1] If the astronauts were "over" for 7½ milliseconds, that would be somewhere between 1.34x10⁻⁶ and 1.39x10⁻⁶ of an orbit. Earth's circumference (at the equator) being approximately 40,000 kilometres (24,850 miles), the station was apparently "over" for a ground distance of between 53.9 m and 55.7 m (177 to 183 feet). That would imply quite a large property, but may also consider the astronauts' locations within the ISS, which is 109 m (356 feet) long. (The effect of angular size is small in this case because the ISS's elevation is small compared to the radius of the Earth. The route traced by the ISS in orbit is only slightly larger than its projection at ground level.)

The caption makes Cueball's statement even less impressive, alleging that statements like it are correct in many places. This would make it uninteresting as a coincidence. It can only happen for latitudes of less than 51.64° north or south, which is as far as the orbital inclination of the ISS takes it, leaving almost 21.6% of the Earth's surface never directly "over"ed. Nonetheless, these areas of the globe will be, overall, significantly more sparsely populated than those that are "over"ed, meaning that the claim could be made in much more than 88.4% of places, assuming that by "places" we mean "properties where people are likely to be having dinner".

The title text suggests that Cueball didn't want a gift (a bottle of wine) from the astronauts. The kinetic energy of a 1.2 kg (full) bottle of wine travelling at the linear velocity of the International Space Station (8000 m/s) is on the order of 40 megajoules. The gravitational potential energy of that mass on the Earth's surface (equatorial radius of 6,378 km) is 75.08 MJ, and its gravitational potential energy at an elevation of 408 km is 70.56 MJ, a difference of 4.52 MJ[2], and that would be converted to kinetic energy if it were to fall. For comparison, the kinetic energy of a fully loaded semi-truck (max legal weight 80,000 pounds or ~36 tonnes) at 70mph (110km/h; a typical highway speed limit for passenger cars) is around 17 megajoules. A bottle with more than 2½ times the kinetic energy of that would be hard to keep on the table, and would likely do damage to people or things that tried to keep it there. [citation needed] However, this would assume that the bottle somehow survives its descent through the Earth's atmosphere intact, which seems unlikely.

This comic was posted the same day as the American release of a film set on the ISS (conveniently named I.S.S.), and just a day after the latest flight to the station by a Crew Dragon flight had temporarily increased the occupants from the normal seven residents to eleven.


[Cueball, Megan, Ponytail, and Hairbun are eating around a table. Cueball is leaning on the back of his chair and has his palm out.]
Cueball: We don't have houseguests often, but we once had six astronauts over for dinner.
Hairbun: Oh, wow!
Cueball (muttering): …for 7½ milliseconds in mid-August 2012.
[Caption below the panel:]
If you spend enough time looking at orbital records and property lines, you can make this claim in a lot of places.

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Bot's down so i took the liberty of making the page myself someone, i guess(talk i guess|le edit list) 03:12, 20 January 2024 (UTC)

The bot isn't actually down. I think you just saw the comic before it did! —theusaf (talk) 03:37, 20 January 2024 (UTC)
If that's the case i find it really weird that Randall posted at *checks time* 10:40 PM... uncharacteristically late upload from my experience, assumed bot was down someone, i guess(talk i guess|le edit list) 03:47, 20 January 2024 (UTC)

Dining room is 50 meters long? ----Bob thé Farmer----

I don't think that's how long they were over the dining room, but how long they were over the property. 16:35, 20 January 2024 (UTC)

It is quite curious that this comic was published exactly when an italian wannabe astronaut (twice discarded by ESA) finally managed to get into outer space by having the italian armed forces pay for his ticket, so now he's on ISS as a *guest*. Of course it's impossible that Randal was hinting at this, but it's an amazing coincidence. -- 17:26, 20 January 2024 (UTC)

Noting in the Explanation that the length of the ISS solid angle 'area' is going to be a footprint slightly smaller than the stated size of the ISS (not by much, as it isn't really that far up, compared with how far the centre of the Earth is down, but it will be smaller. Also that (by my own from-first-principle calculations - please do check my stated working assumptions given in the relevent Edit Summary, or just do it yourself from scratch) slightly over a fifth of the Earth's surface never gets to experience the ISS being directly overhead. I was going to enumerate the sort of 'general chance that any given point at any given latitude might have the ISS above it', perhaps then to shove overflying speed (assuming zero eccentricity - which it pretty much is), compared with any given proportion of a surface latitude (assuming zero Earth oblateness - even though it is certainly a little bit, even at first approximation). But that seems overkill to actually Explain. Though I think it will make an interesting graph of +/-latitude vs overlfly 'timeshare' so I'll perhaps do that for my own entertainment momentarily. 20:34, 20 January 2024 (UTC)

Alright, who's going to start trying to narrow down the specific places where this comic could be set, assuming a reasonable definition of "dinnertime" and "mid-August"? Not it. Reschultzed (talk) 16:49, 21 January 2024 (UTC)

If anyone is interested, his guests that day would have been ISS Expedition 32: Gennady Padalka, Sergei Revin, and Yuri Malenchenko of Russia, Joseph M. Acaba and Sunita Williams of the US, and Akihiko Hoshide of Japan. 17:13, 21 January 2024 (UTC)

Someone needs to make a calculator for this. I need to use this statement but I also don't want to be flat out wrong. Like, enter in a GPS coordinate and you get sets of dates the ISS was overhead and who was in it. 18:14, 21 January 2024 (UTC)

I think both the energy measurements should be in either kilojoules or megajoules, but not both. I had to re-read that back and forth a few times to sort out the decimal shifting.RandalSchwartz (talk) 21:03, 21 January 2024 (UTC)

Interesting how these things evolve. The original comparison was with a baseball at 100 mph (fastball; 0.17 kilojoules), comparing object of somewhat similar size, and for which "kilojoules" seemed the most informative unit. That comparison was replaced with the truck/lorry on the freeway, objects of similar energy, for which megajoules is the most informative unit ... but the edit retained the original kilojoule figure for the bottle. It's all good. 05:03, 22 January 2024 (UTC)

I see I'm not the first person to think a program to calculate this might be cool. Jsnider3 (talk) 15:03, 22 January 2024 (UTC)

"...the station was apparently "over" for a ground distance of between 53.9 m and 55.7 m (177 to 183 feet). That would imply quite a large property..." That doesn't really imply anything about the size of the property, because property size, which implies an area measurement, depends on more than just a linear measurement. A rectangular property with an aspect ratio of 3:1 would be about 10000 sq ft, just under a quarter acre, a little more than 900 sq m. That's a very typical property size (and shape) for a single family home. Hardly "quite large". 16:19, 22 January 2024 (UTC)

Typical response to "how big is a house and garden in the UK", via a search engine, says:
The latest analysis by Quickmove Properties reveals that the average garden size for an English home is an estimated 255 square metres, although this falls to just 81 square metres in Portsmouth
...that's just the garden, as it says. The whole plot (current new-builds) is indicated by:
The average estate house these days is built on approximately 1/12th - 1/10th of an acre about 38ft x 95ft (11.5m x 29m). This size plot may not allow for a very large garden or very good access around the house. When you view a plot always make sure you know the exact position of the boundaries.
...very much the current trend. But see the general demography.
Mine is a bit bigger than that average (3 bedroom, 2-storey, semi-detached, front and back garden, driveway, freestanding brick garage, 50ish years old rather than the current "cramming everything into a very thin plot" trend), I'm also significantly above 51°N so it wouldn't happen here at all. (London is 51.5°, the sprawling non-terraced housing of the more affluent areas of the most southern counties might work. Though some of those are somewhat atypical.) 17:26, 22 January 2024 (UTC)