Bob Stewart (television producer) and Difference between sub-orbital and orbital spaceflights: Difference between pages

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There sometimes appears to be confusion among the general public about the '''difference between sub-orbital and [[orbit]]al spaceflights'''. This article is an attempt to clarify this issue. It also elaborates on the technical implications of the differences between orbital and sub-orbital spaceflights.

'''Bob Stewart''' (1920 - ) is a former [[United States|American]] [[television]] [[game show]] producer. He was active in the TV industry from [[1956]] to [[1992]].

A [[spaceflight]] is a [[flight]] ''into'' or ''through'' [[outer space|space]]. The craft which undertakes a spaceflight is called a [[spacecraft]].

Stewart is known for creating some of the most popular game shows for [[Mark Goodson]]-[[Bill Todman]] Productions. These shows include ''[[To Tell The Truth]]'', ''[[Password (game)|Password]]'', and ''[[The Price Is Right]].'' His biggest success as an independent producer is the ''Pyramid'' series, starting with ''[[Pyramid (game show)|The $10,000 Pyramid]]'' in 1973.

The general public often thinks of [[orbital spaceflight]]s as spaceflights and of [[sub-orbital spaceflight]]s as "something less than actual spaceflights". This is not accurate; both orbital and sub-orbital spaceflights are true spaceflights.

==Stewart with Goodson-Todman==

Strictly speaking, the term ''orbit'' means any [[trajectory]] in general. In common usage the term ''orbit'' refers to a closed trajectory around the Earth (or another central body). The term ''sub-orbital'' refers to a trajectory which intersects the central body before a complete orbit is achieved. An ''orbital spaceflight'' is one which completes an orbit fully around the central body.

Stewart's early broadcasting career included stints at [[NBC]]'s flagship TV and radio stations in New York. In the book ''The Box,'' the native New Yorker says he got the first spark for ''The Price Is Right'' during his tenure as a staff producer at WRCA-TV (now [[WNBC-TV]]) when he watched an auction on 50th Street on his lunch hour. He developed the idea into ''The Auctioneer.''

For a flight from Earth to be a spaceflight, the spacecraft has to ascend from Earth and at the very least go past the [[edge of space]]. The edge of space is, for the purpose of space flight, often accepted to lie at a height of 100 km (62 miles) above mean [[sea level]].

Stewart joined Goodson-Todman Productions in 1956, after he bumped into broadcaster (and future game show producer-host) [[Monty Hall]] on the street and Hall told him he knew Goodson-Todman's attorney. "You got any ideas?" Stewart quoted Hall as asking.

Any flight that goes higher than that is by definition a spaceflight. Where the [[Earth's atmosphere]] ends space begins but the atmosphere fades out gradually so the precise boundary is difficult to ascertain - hence the need for an arbitrary altitude for the [[edge of space]].

==Angular velocity==

''The Price Is Right,'' using some of the ''Auctioneer'' concept, premiered on NBC November 26, 1956, with [[Bill Cullen]] as host. [[CBS]]'s ''To Tell the Truth,'' emceed by [[Bud Collyer]], hit the air less than one month later, on December 18. Stewart said he auditioned the concept to Goodson and his producers by trying to have them guess which of three men had been in the infantry in World War II and was now managing a grocery store.

An orbital spaceflight is achieved when the spacecraft travels around the Earth in space at sufficient lateral velocity (or equivalently, enough [[angular velocity]]) to "miss" the Earth, even though [[gravity]] is still effecting it, and "free-fall" forever. Lateral velocity is the speed of something around an object and it is this which is the critical factor. Although the angular velocity required is a function of the height of the orbit, orbital spaceflight is possible at any altitude beyond the edge of space.

Five years later, in 1961, Stewart hit the jackpot again with ''Password,'' the word-association guessing game emceed by [[Allen Ludden]]. The show, the first to team celebrities and civilians, became the top-rated program in daytime TV and popularized the concept of the bonus round for additional money.

A body which does not have sufficient angular velocity cannot orbit the Earth. The actual speed of a sub-orbital spacecraft could exceed that of an orbital one and the height that a sub-orbital spacecraft attains may even exceed that of an orbital one, but the critical difference between the two - the achieving of an orbit - depends crucially on the angular velocity. Travelling straight up will never result in an orbit, doing so faster than [[escape velocity]] will have the obvious effect and orbit is still not attained.

Stewart was one of a coterie of talented Goodson staff producers who came up with ideas for game shows and segments. Producers such as Stewart, Frank Wayne, and Gil Fates earned Goodson's respect not only for their concepts but for their skill in executing them.

==Difference in the real world==

==Bob Stewart Productions==

That said, typical sub-orbital craft need go only just past the accepted edge of space at 100 km (62.5 miles) for the flight to be a spaceflight. At this arbitrary boundary there is still too much atmosphere present for a long term stable [[low earth orbit]] (LEO). In order to be stable for more than just a few weeks or months the satellite or spacecraft is placed in orbit at an altitude where drag from the atmosphere truly is negligible. A stable LEO is usually at least 350 km up.

Stewart set out on his own in 1965. His first network game show as an independent producer, the memory game ''[[Eye Guess]]'', aired on [[NBC]] from January 3, 1966 to September 26, 1969, and featured close friend [[Bill Cullen]], who emceed ''Price'', as host. His next entry, the [[CBS]] primetime celebrity game show ''The Face Is Familiar'' with host Jack Whitaker, ran from May 7 to September 3, 1966. Another Stewart celebrity game, ''Personality'' (hosted by [[Larry Blyden]]), aired on NBC from 1967 to 1969.

But again, the difference in height should not be overemphasized: Whether the altitude is 100 km or 350 km the distance from the centre of the Earth is only different by less than four percent.

Other than ''Eye Guess,'' Stewart's other moderate early success was ''[[Three on a Match (game show)|Three on a Match]], hosted by Cullen, which aired on NBC from August 2, 1971 to June 28, 1974.

The difference between the lowest speeds required for orbital and sub-orbital space flights is substantial: a spacecraft must reach about 29,000 km/h (18,000 mph) to attain orbit. This compares to the relatively modest 4,000-4,800 km/h (2,500-3,000 mph) typically attained for sub-orbital crafts.

Stewart's biggest success with his own production company, and one of TV's most honored quiz shows, was ''[[Pyramid (game show)]]'' hosted by [[Dick Clark]], which like ''Password'' was a word game. Its March 26, 1973 premiere on CBS marked the first time a quiz show mounted a five-figure or more cash jackpot since the demise of ''100 Grand'' in the mid-1960s.

The important difference in energy requirements between a sub-orbital spaceflight such as that required for the [[Ansari X Prize|X Prize]] and for an orbital spaceflight is that no lateral or angular velocity is required for the sub-orbital flight. The energy required to get to 100 km or even 350 km altitude is dwarfed by the energy required for the necessary lateral velocity of orbital space flight.

''Pyramid'''s network run would span 15 years (and escalating dollar amounts in the title). It has proven to be one of the most enduring game shows, airing almost continuously between first-run network/syndicated airings and cable reruns since 1982. Its nine Emmy awards for best game show rank it second to the Alex Trebek version of ''[[Jeopardy!]],'' which has 10.

In terms of energy: accelerating a spacecraft to [[orbital speed]] requires about 31 times as much net energy as just lifting it to a height of 100 km (together 32 times), see [[Specific orbital energy#Examples|computation]].

The network version of ''Pyramid'' (hosted by Clark) ran from 1973 to 1980 (moving to ABC for its final six years) and from 1982 to 1988 on CBS (with a three month break in the second run). It was also popular in syndication, running once a week from 1974 to 1979 (with Bill Cullen as emcee), daily from January to September 1981 and again daily from 1985 to 1988 (with Clark back at the podium) and again from January 1991 to March 1992 (with [[John Davidson]]).

But this is the energy which must be imparted to the orbiting mass: For a rocket the fuel and oxygen (and their tanks) must be accelerated as well and so the energy requirement is actually much more than the factor of 32 identified. (See the [[rocket equation]] article for a more detailed treatment).

Another version of ''Pyramid'', not helmed by Stewart, aired in syndication from 2002 to 2004, hosted by [[Donny Osmond]].

In terms of the [[semi-major axis|semi-major axes]] <math>a</math> of the [[elliptic orbit]]s: the total [[specific orbital energy]] is {{il|<math>\epsilon=-{\mu\over{2a}}</math>|70}} where <math>\mu\,</math> is the [[standard gravitational parameter]]. Being at rest at the surface of the Earth corresponds to <math>a=R/2</math> (with <math>R</math> the radius of the Earth). Reaching a height of 100 km means an increase of <math>a</math> of 50 km, while a LEO requires an increase of <math>a</math> of more than 3000 km. See also [[orbit equation#Low-energy trajectories|low-energy trajectories]].

Other game shows from Bob Stewart Productions -- mostly word games and puzzles -- included ''[[Jackpot (game show)|Jackpot]]'', ''[[Chain Reaction (game show)|Chain Reaction]]'', ''[[Go (game show)|Go]]'', and ''[[Double Talk]]''. ''Jackpot'' and ''Chain Reaction'' were moderate successes for Stewart in their 1980s runs on cable TV after having relatively brief runs on [[NBC]].

A vertical sub-orbital flight with the same energy as a LEO would reach a height of ca. 7000 km above the surface.

==Retirement==

===Atmospheric reentry a much bigger challenge with orbital flights===

Bob Stewart retired in 1992 after the second run of ''The $100,000 Pyramid'' was cancelled, and his son Sande Stewart took over operations of Bob Stewart Productions. Sande Stewart later produced some game shows on his own, including ''[[Inquizition]]'', ''[[Hollywood Showdown]]'', and ''[[Powerball]] Instant Millionaire''.

Because of that speed difference, '''atmospheric reentry is much more difficult for orbital flights than it is for sub-orbital flights'''. Note however, that such considerations only apply to orbital flights where the vehicle needs to return to Earth intact. If the vehicle is, say, a satellite that is ultimately expendable, then there naturally is no need to worry about reentry.

Returning craft though (including all potentially manned craft), have to find a way of slowing down as much as possible while still in higher atmospheric layers and avoid plunging downwards too quickly. To date (as of 2004), the problem of deceleration from orbital speeds has mainly been solved through [[aerobraking]], ie. using the atmospheric drag itself to slow down. On an orbital space flight initial deceleration is provided by the retrofiring of the craft's rocket engines. Aerobraking in turn has so far mainly been achieved through orienting the returning space craft to fly at a high drag attitude coupled with ultra strong heat shields on the space craft, to protect against the high temperatures generated by atmospheric compression and friction caused by passing through the atmosphere at supersonic speeds. The thermal energy is dissipated mainly as infrared radiation. Sub-orbital space flights, being at a much lower speed, do not generate anywhere near as much heat upon re-entry.

Bob Stewart Productions was sold to [[Sony Pictures Entertainment]] in the mid [[1990s]], and many of Bob Stewart's creations air frequently on [[Game Show Network]]. Stewart himself has participated in panels and special events related to quiz shows, including the annual Game Show Congress gatherings in the Los Angeles metropolitan area.

This has allowed maverick aircraft designer [[Burt Rutan]] recently (July 2004) to demonstrate an alternative or complementary approach to heat shield dependant [[reentry]] with the suborbital [[SpaceShipOne]]. It may be possible that the concepts utilized in SpaceShipOne's design can be applied to orbital space craft design and result in a markedly reduced need for a massive heat shield. Currently however, the need for an ultra high-performance and ultra reliable heat shield is a major difference between crafts designed for orbital flights (as opposed to sub-orbital ones), demonstrated in the [[Mercury program]] wherein the orbital flights used a typical ablative [[heat shield]] while the sub-orbital flights relied simply on a large metal heat-sink.

==External links==

* [http://members.lycos.co.uk/gameshowpage/GSP.html The Bob Stewart Fan Page]

* {{imdb|name=Bob Stewart|id=0829212}}

If we can transport fuel tanks into orbit, which returning spaceships can use to brake from their orbiting speed to zero or a low speed, re-entry can be made much safer and easier. The big problem now is that spaceships have practically no fuel left when they reach orbit, and have to get home again without being able to slow down before hitting the atmosphere.

[[Category:U.S. television producers|Stewart, Bob]]

==Summary==

* Sub-orbital spaceflights flights are spaceflights just as orbital flights are.

* Both go beyond the atmosphere and past the edge of space.

* A sub-orbital flight may reach a higher height than an orbital one.

* The most important requirement for an orbital flight over a sub-orbital one is speed.

* The [[shock wave]] produced by high speed atmospheric reentry generates lots of heat from which the spacecraft must be protected.

== See also ==

* [[Boundary to space]]

* [[Low Earth orbit]]

* [[Atmospheric reentry]]

* [[Aerobraking]]

[[Category:Spaceflight]]