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1461: Payloads

2014-12-17T17:36:28Z

Screamsquad: Fixed payload of unlabeled rocket (21 horses * 450 kg/horse)

{{comic
| number = 1461
| date = December 17, 2014
| title = Payloads
| image = payloads.png
| titletext = With a space elevator, a backyard full of solar panels could launch about 500 horses per year, and a large power plant could launch 10 horses per minute.
}}

A larger version of the image can be found [http://imgs.xkcd.com/comics/payloads_large.png here].

==Explanation==
{{incomplete|Discuss space elevator aspect from title text, touch on horsepower vs [[rocket equation]], thrust, specific impulse, payload to orbit. E.g., compare with question of a horse getting itself into orbit?}}
This comic lists the payload capacity of several launch vehicles, and the mass of several spacecraft, in number of horses. This could be related to Randall's hobby of abusing dimensional analysis, as horses/ship is technically a perfectly acceptable derived unit, provided the size of a horse is standard (in this comic it appears that 'one horse' is defined as 450 kg). In cases where the mass is less than one horse, an alternative measure of dogs has been used, where one dog appears to be roughly 40 kg. In the case of {{w|Vanguard 1}}, even a dog is too large a measure, so instead the unit squirrel is used to represent its 1.47 kg mass.

The overall comic is an allusion to {{w|horsepower}}, a similar-sounding but completely different concept. Horsepower is a measurement of {{w|power (physics)|power}} ({{w|work (physics)|work}} per unit time). Another commonly referenced unit for power is the {{w|watt}}. 1 horsepower is meant to be approximately the amount of power a horse can deliver. In contrast, Randall uses the horse to measure {{w|mass}} (of spacecraft themselves, and of the payload they carry).

The top pane of the comic shows the mass of various spacecraft, while the bottom shows the amount of mass they can deliver to {{w|low earth orbit}}. There are also several joke insertions. In the top, one is T-Rex. In the bottom, another is Pegasus (the payload capacity given as one Pegasus); this is a reference to both Pegasus {{w|Pegasus (rocket)|the rocket}} and Pegasus the {{w|Pegasus|mythical flying stallion}}. Atlas-Centaur is also measured in centaurs, a reference to the half-human half-horse creatures of Greek mythology. The bottom also gives the 1981 {{w|Oldsmobile}} as 4 horses; presumably, this is actually the number of horses the Oldsmobile could tow, rather than launch into low earth orbit.

The Pegasus, 1981 Oldsmobile, and Stratolaunch spacecraft are depicted horizontally, presumably because these vehicles launch from a horizontal starting position and use forward momentum to facilitate their launch.

There is an unlabeled launch vehicle below the H-11A near 2002. The unlabeled vehicle has a playload mass of 21 horses (9450 kg).

===Tables===
The tables below contain data relating to each entry on the comic image.

*Name - Should be as shown in the comic
*Launch Date - Date of first flight
*Mass/Payload (Horses) - Value as given in comic
*Mass/Payload (kg) - Independently researched value

{|
|- style="vertical-align:top;"
|

{| class="wikitable sortable"
!colspan="4"|Spacecraft Mass
|-
!Spacecraft
!Launch Date <sup>''{{w|ISO 8601}}''</sup>
!Mass (Horses)
!Mass (kg)
|-
|{{w|Sputnik 1|Sputnik}}
|1957-10-04
|2 Dogs
|83.6
|-
|{{w|Vanguard 1}}
|1958-03-17
|Squirrel
|1.47
|-
|{{w|Pioneer 5}}
|1960-03-11
|Large Dog
|43
|-
|{{w|Venera 1}}
|1961-02-12
|1
|643.5
|-
|{{w|Mariner 2}}
|1962-08-27
|3 Dogs
|202.8
|-
|Apollo
|
|67
|
|-
|{{w|Venera 7}}
|1970-08-17
|3
|1,180
|-
|{{w|Pioneer 10}}
|1972-03-03
|7 Dogs
|258.8
|-
|{{w|Skylab}}
|1973-05-14
|171
|77,088
|-
|{{w|Venera 9}}
|1975-06-08
|11
|4,936
|-
|{{w|Voyager 2}}
|1977-08-20
|2
|721.9
|-
|Shuttle (Total)
|
|206
|
|-
|Shuttle (Payload)
|
|54
|
|-
|{{w|Mir}}
|1986-02-20
|288
|129,700
|-
|T-Rex
|
|15
|6,800
|-
|{{w|Hubble}}
|1990-04-24
|25
|11,110
|-
|{{w|Compton Gamma Ray Observatory}}
|1991-04-05
|38
|17,000
|-
|{{w|Corona (Satellite)|Keyhole 3}}
|
|40
|
|-
|{{w|International Space Station}}
|1998
|932
|450,000
|-
|{{w|Cassini-Huygens|Cassini}}
|1997-10-15
|11
|5,300
|-
|{{w|Huygens (spacecraft)|Hyugens Lander}}
|1997-10-15
|1
|319
|-
|{{w|Rosetta (spacecraft)|Rosetta}}
|2004-03-02
|6
|2,900
|-
|{{w|Opportunity (rover)|Opportunity}}
|2003-07-07
|5 Dogs
|185
|-
|{{w|Dawn (spacecraft)|Dawn}}
|2007-09-27
|3
|1,240
|-
|{{w|TerreStar-1|Terrastar}}*
|July 2009-07-01
|15
|6,910
|-
|{{w|Dragon (spacecraft)|Dragon}}
|2010-12-08
|17
|
|-
|{{w|Tiangong-1}}
|2011-09-29
|19
|8,506
|-
|{{w|Curiosity (rover)|Curiosity}}
|2011-11-26
|2
|900
|-
|{{w|Corona (Satellite)|Keyhole 7}}
|
|40
|
|-
|{{w|Orion (spacecraft)|Orion (Capsule)}}
|2014-12-05
|20
|8,913
|-
|{{w|James Webb Space Telescope|James Webb Telescope}}
|
|14
|6,200
|-
|{{w|Orion (spacecraft)|Orion}}
|2014-12-05
|20
|8,913
|-
|{{w|Orion Service Module}}
|
|25
|12,000
|-
|{{w|Deep Space Habitat|Orion Deep Space Habitat}}
|
|65
|
|}

Terrastar is believed to be a mis-spelling of {{w|TerreStar-1|TerreStar}}, based on its mass and launch date.

|

{| class="wikitable sortable"
!colspan="4"|Lauch Vehicle Capacity
|-
!Spacecraft
!Launch Date <sup>''{{w|ISO 8601}}''</sup>
!Payload (Horses)
!Payload (kg)
|-
|{{w|Sputnik (rocket)|Sputnik Launcher}}
|1957-10-04
|1
|500
|-
|{{w|Thor-Able|Thor}}
|1958-04-24
|3 Dogs
|120
|-
|{{w|Mercury-Atlas}}
|1960-07-29
|3
|1,360
|-
|{{w|Saturn I}}
|1961-10-27
|20
|9,070
|-
|{{w|Proton-K}}
|1967-03-10
|44
|
|-
|{{w|Atlas-Centaur}}
|1962-05-08
|8 Centaurs
|
|-
|{{w|Titan IIIA}}
|1964-09-01
|7
|3,100
|-
|{{w|Saturn IB}}
|1966-02-26
|45
|21,000
|-
|{{w|Soyuz (rocket)|Soyuz}}
|1966-11-28
|14
|6,450
|-
|{{w|Saturn V}}
|1967-11-09
|262
|118,000
|-
|{{w|Black Arrow}}
|1969-06-27
|4 Dogs
|135
|-
|{{w|N1 (rocket)|N1}}
|1969-02-21
|211
|90,000*
|-
|{{w|Long March 1}}
|1969-11-16
|2
|300*
|-
|{{w|N-I (rocket)|N-I}}
|1975-09-09
|4
|1,200*
|-
|{{w|Delta 0100|Delta 0900}}
|1972-07-23
|3
|1,300
|-
|{{w|Ariane 1}}
|1979-12-24
|3
|1,400
|-
|{{w|Satellite Launch Vehicle|SLV}}
|1979-08-10
|1 Dog
|40
|-
|{{w|N-II (rocket)|N-II}}
|1981-02-11
|4
|2,000
|-
|{{w|Oldsmobile#1970s-1980s|1981 Oldsmobile}}
|1981
|4
|
|-
|{{w|ASLV}}
|1987-03-24
|4 Dogs
|150
|-
|{{w|Long March 4A}}
|1988-09-06
|9
|4,000
|-
|{{w|Ariane 4}}
|1988-06-15
|16
|5,000-7,600*
|-
|{{w|Shavit}}
|1988-09-19
|6 Dogs
|350-800*
|-
|{{w|Energia}}
|1987-05-15
|218
|100,000*
|-
|{{w|Pegasus (rocket)|Pegasus}}
|1990-04-05
|1 Pegasus
|443
|-
|{{w|Atlas I}}
|
|13
|
|-
|{{w|PSLV}}
|
|8
|
|-
|{{w|J-I}}
|
|2
|
|-
|{{w|Long March 3B}}
|
|27
|
|-
|{{w|H-IIA}}
|
|22
|
|-
|(unlabelled) {{w|Delta IV#Delta IV Medium|Delta IV M}}?
|
|21
|
|-
|{{w|Delta IV Heavy|Delta IV-H}}
|
|64
|
|-
|{{w|Falcon 1}}
|
|1
|
|-
|{{w|Ariane 5#Variants|Ariane 5ES}}
|
|47
|
|-
|{{w|H-IIB}}
|
|37
|
|-
|{{w|UNHA}}
|
|2 Dogs
|
|-
|{{w|Atlas V|Atlas V 541}}
|
|38
|
|-
|{{w|Falcon 9}}
|
|29
|
|-
|{{w|Antares (rocket)|Antares}}
|
|14
|
|-
|{{w|Stratolaunch}}
|
|14
|
|-
|{{w|Falcon Heavy}}
|
|118
|
|-
|{{w|Space Launch System|SLS Block 1}}
|
|156
|
|-
|{{w|Space Launch System|SLS Block 1B}}
|
|217
|
|-
|{{w|Space Launch System|SLS Block 2}}
|
|289
|
|}

|}

==Transcript==
{{incomplete transcript}}

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Animals]]
[[Category:Space]]

Talk:1461: Payloads

2014-12-17T16:20:51Z

Screamsquad:

It's possible he's talking about [http://poorlydrawnlines.com/comic/earth-and-moon/ this comic].
[[Special:Contributions/108.162.249.203|108.162.249.203]] 07:20, 17 December 2014 (UTC)

I think he used horses as a reference to the unit of work, horse power, but in this case instead of being the 550 foot pounds per second, it is the force required to put a horse at that altitude
[[Special:Contributions/199.27.128.195|199.27.128.195]] 08:10, 17 December 2014 (UTC)
:The top one clearly says "Spacecraft mass" and the bottom says "Capacity" (which is normally either the mass or volume something can hold), so I don't think either refers to force. [[Special:Contributions/173.245.54.175|173.245.54.175]] 08:32, 17 December 2014 (UTC)

Horses might also be used as a length unit... I am wondering if this is somehow related to the size of SRBs [http://www.snopes.com/history/american/gauge.asp] ;-) {{unsigned|Ld75}}
:There is the famous tail (no pun intended) of how the width of the Space Shuttles SRBs are related to the width of a horses, er, um, butt -- which apparently is not true. However, similarly to the "Upgoer Five", Randall may just be trying to relate a very difficult to grasp concept (weight of a huge object) to something that with which a large number of people may be familiar. [[User:Jarod997|Jarod997]] ([[User talk:Jarod997|talk]]) 14:34, 17 December 2014 (UTC)

A few mass calculations: (All masses from wikipedia)

* ISS - 450,000 kg / 932 Horses = 483 kg/Horse
* Skylab - 77,088 kg / 171 Horses = 450 kg/Horse
* Mir - 129,700 kg / 286 Horses = 453 kg/Horse
* Shuttle Payload - 24,400 kg / 54 Horses = 452 kg/Horse
* Compton GRO - 17,000 kg / 38 Horses = 447 kg/Horse

It looks like Randall probably used 450kg as a standard horse, which seems like a fairly average weight for a {{w|Horse#Size and Measurement|horse}}. --[[User:Pudder|Pudder]] ([[User talk:Pudder|talk]]) 09:06, 17 December 2014 (UTC)

Curious: the Atlas-Centaur rocket is listed as lifting Centaurs, not horses. [[Special:Contributions/141.101.98.244|141.101.98.244]] 09:11, 17 December 2014 (UTC)

:Plus the Pegasus rocket is labelled as lifting one (mythical, horse-sized?) Pegasus. I took this as synchronicity, but currently someone (who missed the Centaur reference in the part of the main text about "joke additions/deviations") who edited the the main text seems to think that it's purely a mythical reference. [[Special:Contributions/141.101.98.245|141.101.98.245]] 13:27, 17 December 2014 (UTC)

The Keyhole captions are wrong; assuming 450 kg/horse, 40 horses for the [[wikipedia:KH-7 Gambit|Keyhole 7]] would be around 18,000 kg. Documents declassified a couple of years ago give the mass as around 2,000 kg. The [[wikipedia:Corona (satellite)|Keyhole 3]] was even smaller. The mass and dates are about right for [[wikipedia:KH-11 Kennan|Keyhole 11]] satellites but I don't know where the 3 and 7 have come from (the dates are wrong for the third and seventh Keyhole 11s) [[Special:Contributions/141.101.99.85|141.101.99.85]] 09:43, 17 December 2014 (UTC)

Initially I thought that the position of 'T Rex' along the X axis (approx 1985) may be a link to the band {{w|T. Rex (band)|T.Rex}}, but according to wiki that was 1967-1977. I guess it could be a random date, but thats not usually Randall's style... --[[User:Pudder|Pudder]] ([[User talk:Pudder|talk]]) 10:51, 17 December 2014 (UTC)
:The T Rex "Sue" was discovered in August 1990. Not quite right, either. [[Special:Contributions/108.162.250.214|108.162.250.214]] 11:10, 17 December 2014 (UTC)
::Perhaps a reference to the date of 'Jurassic Park'? Not sure exactly when that came out but I think it's in the right range. [[Special:Contributions/108.162.238.189|108.162.238.189]] 14:55, 17 December 2014 (UTC)
:::Hadn't thought of that.. Though after checking, {{w|Jurassic Park}} was released 1993, and I believe set in 1990. Still doesn't seem to tie up.. --[[User:Pudder|Pudder]] ([[User talk:Pudder|talk]]) 15:22, 17 December 2014 (UTC)

The Oldsmobile is probably a reference to the movie ''{{w|Mom and Dad Save the World}}''. The title characters' station wagon was from around that era -- and it ''did'' go into space in the movie. --[[User:Aaron of Mpls|Aaron of Mpls]] ([[User talk:Aaron of Mpls|talk]]) 11:47, 17 December 2014 (UTC)

'''Terrastar''' may be referring to [[wikipedia:TerreStar-1|TerreStar-1]], with a launch mass of 6,910 kg, divided by 15 horses is about 460 kg/Horse. This is consistent with the above calculations. [[User:Jarod997|Jarod997]] ([[User talk:Jarod997|talk]]) 14:23, 17 December 2014 (UTC)
:Based on that and its accurate position on the X axis, I would agree with you. I've added it to the table, with a note below. --[[User:Pudder|Pudder]] ([[User talk:Pudder|talk]]) 14:38, 17 December 2014 (UTC)

'''Thor''' may be referring to the [[wikipedia:Thor-Able|Thor-Able]] launch vehicle. First flight of 1958 (good position on the graph), and payload of 120 kg is about 40 kg / dog -- that's a bit high for an average, but depending on the breed it could be accurate. [[User:Jarod997|Jarod997]] ([[User talk:Jarod997|talk]]) 14:58, 17 December 2014 (UTC)
:Yes, I believe that is correct. Added to tables. --[[User:Pudder|Pudder]] ([[User talk:Pudder|talk]]) 15:22, 17 December 2014 (UTC)

Based on horse payload, location on X-axis (time of first launch?), and some general wikipedia browsing, I believe the unlabeled launch vehicle on the bottom is a Delta IV Medium. According to Wikipedia, it was first launched on 11 March 2003, which fits the location on the timeline. It had an LEO payload capacity of 9,420 kg, which equates to 20.9333333 horses at the estimation of 450kg/horse. For reference, all my information was pulled from http://en.wikipedia.org/wiki/Delta_IV#Delta_IV_Medium. [[User:Screamsquad|Screamsquad]] ([[User talk:Screamsquad|talk]]) 16:20, 17 December 2014 (UTC)