User talk:Mrashby9

2015-10-24T20:00:55Z

Mrashby9: Excited by my first tiny contribution, grateful for xkcd explained

Yeah: edited a typo, changed in to is, last sentence, third paragraph above tables for 1461, payloads. Enough working memory to create an account then add my documented edit. Thx xkcd explained folks for the tools & entry to Wikipedia.[[User:Mrashby9|Mrashby9]] ([[User talk:Mrashby9|talk]]) 20:00, 24 October 2015 (UTC)

1461: Payloads

2015-10-24T18:41:42Z

Mrashby9: Typo

{{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==
This comic is an infographic representing the launch mass of various spacecraft and artificial satellites, and the {{w|Low Earth orbit|low Earth orbit}} payload capacity of various space launch vehicles. Rather than using standard units of mass such as kilograms or pounds, Randall has assigned values based on the mass of a horse. Based on cross checking researched masses and payloads with the number of horses depicted, it appears that one horse unit is defined as 450 kg (with an average of 432.82 kg), or perhaps 1000 lb. 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 (with an average of 48.05 kg, or perhaps 100 lb.). 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 (3.5 lb.?) mass.

The overall comic may be 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 particular spacecraft, and of the maximum payload launch vehicles can carry).

The top pane of the comic (black background) shows the mass of various spacecraft, while the bottom (white background) shows the payload capacity (to low Earth orbit) of launch vehicles. Along the bottom of the image is a timeline, relating to the launch date of the entries.

There are also several joke insertions:
*T-Rex - A dinosaur, but fairly unlikely to be found orbiting Earth.
*Pegasus - An actual {{w|Pegasus (rocket)|launch vehicle}}, but also the name of a {{w|Pegasus|mythical flying stallion}}. The payload is given as "one Pegasus", which comes out to be slightly less than "one horse".
*Atlas-Centaur - Again, an actual {{w|Atlas-Centaur|launch vehicle}}, but also a reference to the half-human half-horse creatures of Greek mythology. The payload is given in "centaurs", which come out to be slightly more than "horses".
*1981 {{w|Oldsmobile}} - Not a launch vehicle, but in fact a car. The payload is given as 4 horses, which may relate to the carrying capacity (by weight) of the Oldsmobile, not the ability of an Oldsmobile to launch that payload into low Earth orbit. While there are no known examples of an Oldsmobile reaching low Earth orbit, the [[w:Blues Brothers]] movie shows an Oldsmobile performing a very, very long flight, and this might be the reason why Randall chose this specific car.

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

An unlabelled launch vehicle is shown below the H-IIA near 2002. From the payload and date it is believed to represent the {{w|Delta IV#Delta IV Medium|Delta IV M}}. Whether its lack of labelling is intended or a mistake is unknown.

The title text refers to a favourite subject of Randall's - The {{w|space elevator}}. A space elevator is a (currently theoretical) mechanism for travelling into space, consisting of a very long (>35,000 km) cable and counterweight connected to the Earth at the equator. The cable rotates at the same rate as the earth, and thus appears stationary when viewed from earth. It is then possible to climb the cable into space, and even use it as a slingshot to launch vehicles.

In the title text, the amount of power required to lift a horse into space has been investigated, with the launch capacity of a back yard solar array and large power station compared. A rudimentary (and possibly incorrect) calculation in the discussion section puts the required power output of the solar array at 315 kW and the power station at 3.3 GW.

===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

Where the researched launch date or mass/payload don't seem to match the comic, they should be identified with ?

{|
|- style="vertical-align:top;"
|
{| class="wikitable sortable"
!colspan="4"|Spacecraft mass
|-
!Spacecraft
!Launch date ''{{w|ISO 8601}}''
!Mass (horses)
!Mass (kg)
|-
|{{w|Sputnik 1|Sputnik}}[http://www.astronautix.com/craft/sputnik1.htm]
|1957-10-04
|2 Dogs
|83.6
|-
|{{w|Vanguard 1}}[http://www.astronautix.com/craft/vanuard1.htm]
|1958-03-17
|Squirrel
|1.47
|-
|{{w|Pioneer 5}}[http://www.astronautix.com/craft/pioneer5.htm]
|1960-03-11
|Large Dog
|43
|-
|{{w|Venera 1}}[http://www.astronautix.com/craft/venra1va.htm]
|1961-02-12
|1
|643.5
|-
|{{w|Mariner 2}}[http://www.astronautix.com/craft/marner12.htm]
|1962-08-27
|3 Dogs
|202.8
|-
|{{w|Apollo Command/Service Module|Apollo}}[http://www.astronautix.com/craft/apolocsm.htm]
|1964-05-28
|67
|30,329
|-
|{{w|Venera 7}}[http://www.astronautix.com/craft/ven3vv70.htm]
|1970-08-17
|3
|1,180
|-
|{{w|Pioneer 10}}[http://www.astronautix.com/craft/pior1011.htm]
|1972-03-03
|7 Dogs
|258.8
|-
|{{w|Skylab}}[http://www.astronautix.com/craft/skylab.htm]
|1973-05-14
|171
|77,088
|-
|{{w|Venera 9}}[http://www.astronautix.com/craft/venra4v1.htm]
|1975-06-08
|11
|4,936
|-
|{{w|Voyager 2}}[http://www.astronautix.com/craft/voyager.htm]
|1977-08-20
|2
|800
|-
|{{w|Space Shuttle|Shuttle (Total)}}[http://www.braeunig.us/space/specs/orbiter.htm]
|1981-04-12
|206
|104,328?
|-
|{{w|Space Shuttle|Shuttle (Payload)}}
|1981-04-12
|54
|24,400
|-
|{{w|Mir}}
|1986-02-20
|288
|129,700
|-
|T-Rex
|N/A
|15
|6,800
|-
|{{w|Hubble}}[http://www.astronautix.com/craft/hst.htm]
|1990-04-24
|25
|11,110
|-
|{{w|Compton Gamma Ray Observatory}}[http://www.astronautix.com/craft/gro.htm]
|1991-04-05
|38
|17,000
|-
|{{w|Corona (satellite)|Keyhole 3}}†
|1961
|40
|1150
|-
|{{w|International Space Station}}
|1998
|932
|450,000
|-
|{{w|Cassini-Huygens|Cassini}}
|1997-10-15
|11
|5,300
|-
|{{w|Huygens (spacecraft)|Huygens 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}}[http://www.astronautix.com/craft/dawn.htm]
|2007-09-27
|3
|1,240
|-
|{{w|TerreStar-1|Terrastar}}*
|2009-07-01
|15
|6,910
|-
|{{w|Dragon (spacecraft)|Dragon}}[http://www.astronautix.com/craft/dragon.htm]
|2010-06-04
|17
|8,000
|-
|{{w|Tiangong-1}}
|2011-09-29
|19
|8,506
|-
|{{w|Curiosity (rover)|Curiosity}}
|2011-11-26
|2
|900
|-
|{{w|KH-7 Gambit|Keyhole 7}}†
|1963-07-12
|40
|2000
|-
|{{w|Orion (spacecraft)|Orion (Capsule)}}
|2014-12-05
|20
|8,913
|-
|{{w|James Webb Space Telescope|James Webb Telescope}}
|2018-08 (Projected)
|14
|6,200
|-
|{{w|Orion (spacecraft)|Orion}}
|2014-12-05
|20
|8,913
|-
|{{w|Orion Service Module}}
|2017 (Projected)
|25
|12,000
|-
|{{w|Deep Space Habitat|Orion Deep Space Habitat}}
|2021 (Projected)
|65
|28,750 & 45,573
|}
<nowiki>*</nowiki>Terrastar is believed to be a mis-spelling of {{w|TerreStar-1|TerreStar}}, based on its mass and launch date.

<nowiki>†</nowiki>Keyhole 3 and 7 seem to be errors; Keyhole 3 satellites were launched between 1961 and 1962 and Keyhole 7 between 1963 and 1967. 
The dates and masses in the comic more closely correspond to the {{w|KH-11 Kennan|Keyhole 11}}.
|

{| class="wikitable sortable"
!colspan="4"|Launch vehicle capacity
|-
!Spacecraft
!Launch date ''{{w|ISO 8601}}''
!Payload (horses)
!Payload (kg)
|-
|{{w|Sputnik (rocket)|Sputnik Launcher}}[http://www.astronautix.com/lvs/spuk71ps.htm]
|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}}[http://www.astronautix.com/lvs/protonk.htm]
|1967-03-10?
|44
|19,760
|-
|{{w|Atlas-Centaur}}[http://www.astronautix.com/lvs/atlntaur.htm]
|1962-05-08
|8 Centaurs
|3,630
|-
|{{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
|N/A (Model dependent)
|-
|{{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}}[http://www.astronautix.com/lvs/atlasi.htm]
|1990-07-25
|13
|3,630?
|-
|{{w|PSLV}}
|1993-09-20
|8
|3250
|-
|{{w|J-I}}[http://www.astronautix.com/lvs/j1.htm]
|1996-02-11
|2
|850
|-
|{{w|Long March 3B}}
|1996-02-14
|27
|12,000
|-
|{{w|H-IIA}}
|2001-08-29
|22
|10,000
|-
|(unlabelled) {{w|Delta IV#Delta IV Medium|Delta IV M}}?*
|2002-09-20
|21
|4200-6882
|-
|{{w|Delta IV Heavy|Delta IV-H}}[http://www.astronautix.com/lvs/delheavy.htm]
|2004-12-21
|64
|28,790
|-
|{{w|Falcon 1}}
|2006-03-24
|1
|670 (Proposed)
|-
|{{w|Ariane 5#Variants|Ariane 5ES}}[http://www.astronautix.com/lvs/arine5es.htm]
|2008-03-09
|47
|21,000
|-
|{{w|H-IIB}}
|2009-09-10
|37
|19,000?
|-
|{{w|Unha}}
|2009-04-05
|2 Dogs
|100[http://www.ucsusa.org/sites/default/files/legacy/assets/documents/nwgs/Wright-Analysis-of-NK-launcher-3-18-09.pdf]
|-
|{{w|Atlas V|Atlas V 541}}
|2011-11-26
|38
|17,443[http://www.lockheedmartin.com/data/assets/ssc/cls/AVUG_Rev11_March2010.pdf]
|-
|{{w|Falcon 9}}
|2013-09-29
|29
|13,150
|-
|{{w|Antares (rocket)|Antares}}
|2013-04-21
|14
|6,120
|-
|{{w|Stratolaunch carrier aircraft|Stratolaunch}}
|2016 (Projected)
|14
|6,100
|-
|{{w|Falcon Heavy}}
|2015 (Projected)
|118
|53,000
|-
|{{w|Space Launch System|SLS Block 1}}
|2018-11 (Projected)
|156
|70,000[http://www.nasa.gov/pdf/664158main_sls_fs_master.pdf]
|-
|{{w|Space Launch System|SLS Block 1B}}
|2021 (Projected)
|217
|100,000?
|-
|{{w|Space Launch System|SLS Block 2}}
| 2030's (Projected)
|289
|130,000[http://www.nasa.gov/pdf/664158main_sls_fs_master.pdf]
|}

*The unlabelled launch vehicle is believed to be the Delta IV M, based on its payload and date.
|}

==Transcript==
{{incomplete transcript}}

{{comic discussion}}
[[Category:Comics with color]]
[[Category:Animals]]
[[Category:Space]]

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1461: Payloads