Question: What is the original format of the series with the fictional character Trillian Astra?

Context paragraphs:
America's Next Top Model (cycle 23): The twenty-third cycle of "America's Next Top Model" premiered on December 12, 2016 on VH1, as a result of the revival of the series following its cancellation by The CW.  As opposed to the past three cycles, this cycle followed the series' original format of an all-female contest.

1958 Night Series Cup: The 1958 VFL Night Premiership Cup was the Victorian Football League end of season cup competition played in August and September of the 1958 VFL Premiership Season.  This was the third year the VFL Night Series had existed.  In last years competition, each of the day finalists were duly defeated upon entry and their addition to the competition resulted in a drawn-out and complicated fixture of matches.  The VFL thus elected to return to the original format for this year's competition as previously used in the 1956 Night Series Cup.  Run as a knock-out tournament, it was contested by the eight VFL teams that failed to make the 1958 VFL finals series.  Games were played at the Lake Oval, Albert Park, then the home ground of South Melbourne, as it was the only ground equipped to host night games.  St Kilda went on to win the night series cup, defeating Carlton in the final by 8 points.

Farmer Wants a Wife: Farmer Wants a Wife is a reality television series developed by Fremantle Media.  The first edition premièred in the United Kingdom on ITV in 2001.  However, the original format of the programme is likely to date back to the TV programme "Bauer sucht Bäuerin", which was broadcast in 1983 on SF DRS in Switzerland.  The basic structure of the programme is that a number of farmers are presented with women from the city, from whom they choose one to be their spouse.

Quelli dell'Intervallo Cafe: Quelli dell'Intervallo Cafè is an Italian television series, second spin-off of the best known Quelli dell'intervallo, original format of As The Bell Rings.

Marika Makaroff: Marika became known for there work as a journalist in both television and radio.  She worked series such as "Jyrki, Wild bunch" and "Under construction Finland".  In 2003 she led the series "Makaroff & Modig""," a political talk show she hosted together with journalist Silvia Modig.  In 2005 Marika became the CEO of Fremantle Media Finland.  In 2011 she became the Creative director of the company, overseeing all creative development in the Nordics.  In 2014 she moved to Stockholm to become the CEO of Friday TV.  In 2015 she became the creative director of Filmlance international, that is known for creating original format of the TV-series The Bridge.

Off Their Rockers (Australian TV series): Off Their Rockers is an Australian comedy television series aired on The Comedy Channel on 13 January 2013 until 3 March 2013.  It is based on the U.S. version titled "Betty White's Off Their Rockers."  The original format however is from a Belgian television show 'Benidorm Bastards', broadcast by 2BE.  The title music used in the international versions is still the original score written by .

Trillian (character): Tricia Marie McMillan, also known as Trillian Astra, is a fictional character from Douglas Adams' series "The Hitchhiker's Guide to the Galaxy".  She is most commonly referred to simply as "Trillian", a modification of her birth name, which she adopted because it sounded more "space-like".  According to the movie version, her middle name is Marie.  Physically, she is described as "a slim, darkish humanoid, with long waves of black hair, a full mouth, an odd little knob of a nose and ridiculously brown eyes," looking "vaguely Arabic."

The Amazing Race 8: The Amazing Race 8 (also known as The Amazing Race: Family Edition) was the eighth installment of the US reality television show "The Amazing Race".  Previous installments of "The Amazing Race" featured pairs of adults with a pre-existing relationship but "The Amazing Race 8" featured ten families of four and allowed the participation of minors as young as eight years old.  (This family format had a lukewarm reception and the series returned to the original format of teams of two adults for subsequent seasons.)  Filming ran from July 7, 2005, to July 31, 2005.  The show premiered on Tuesday, September 27, 2005, and concluded on Tuesday, December 13, 2005.

The Hitchhiker's Guide to the Galaxy: The Hitchhiker's Guide to the Galaxy (sometimes referred to as HG2G, HHGTTG or H2G2) is a comedy science fiction series created by Douglas Adams.  Originally a radio comedy broadcast on BBC Radio 4 in 1978, it was later adapted to other formats, including stage shows, novels, comic books, a 1981 TV series, a 1984 computer game, and 2005 feature film.  A prominent series in British popular culture, "The Hitchhiker's Guide to the Galaxy" has become an international multi-media phenomenon; the novels are the most widely distributed, having been translated into more than 30 languages by 2005.

History of the Trans-Am Series: The 'Trans-Am series' is an automobile racing series that was created in 1966 by Sports Car Club of America (SCCA) President John Bishop.  Originally known as the Trans-American Sedan Championship, the name was changed to the Trans-American Championship for 1967 and henceforth.  The series has in fact gone by a variety of different names through the years (too many to list), some linked to sponsors, some not.  It has evolved over time from its original format as a Manufacturers' Championship series for modified passenger sedans and Coupés to its current form as a Drivers' / Manufacturers' Championship Series that is open to GT style racecars.  Champion drivers have been officially recognized, and Drivers' Championship(s) have been awarded since the 1972 season.

Supporting paragraphs: Trillian (character) The Hitchhiker's Guide to the Galaxy
Answer: radio comedy broadcast