A double star is when two stars appear close to each other as seen from Earth.

There are two kinds of double star: visual binaries and optical binaries. Visual binaries are considered to be a true binary star system and lie close enough together in space to interact gravitationally such that the stars orbit each other. Optical binaries (aka optical doubles), on the other hand, are two stars that only appear to be close together, and are actually separated by a great distance in space and are not gravitationally bound to each other, but merely happen to lie in the same line-of-sight when viewed from Earth.

Optical doubles are distinguished from binary stars by observing them for a long period of time, usually years. If the relative motion looks linear, it may be safely assumed that the motion is due to proper motion alone and that they are an optical double. In the case of a true binary, the position angle changes progressively and the distance between the two stars oscillates between a maximum and minimum.

The first recorded discovery of a true binary star system was by Giovanni Battista Riccioli in 1650, when he found Mizar (ζ Ursae Majoris) was a double star. Since that time, the search for double stars has been carried out thoroughly and every star down to the 10th stellar magnitude has been examined. At least 1 in 18 stars in the northern half of the sky which are as bright as 9.0 magnitude is a close double star visible with a telescope.

Examples

Visual binary

• Sirius A and B
• Procyon A and B
• Capella A and B
• Acrux A and B
• Algol A and B

Optical binary

• Winnecke 4

Undetermined status

• Alpha Centauri system (A and B) and Proxima Centauri (= Alpha Centauri C?) Generally considered likely.
• Castor system (Aa/Ab/Ba/Bb and YY Geminorum (= Castor Ca/Cb?) Generally considered likely.
• Mizar system (Aa/Ab/Ba/Bb) and Alcor (= Mizar C?) Generally considered unlikely.

Double Star is a science fiction novel by Robert A. Heinlein, first serialized in Astounding Science Fiction (February, March, April 1956) and published in hardcover the same year. At the 1957 Worldcon it received the Hugo Award for Best Novel of the previous year.

Plot summary

The story, which is told in the first person, centers on a down-and-out actor. Lawrence Smith (stage name Lorenzo Smythe, a.k.a. "The Great Lorenzo"). A brilliant actor and mimic, his self-centeredness has reduced him to sleeping in a coin-operated cubicle. He is down to his last coin when a spaceman hires him to double for a public figure. It is only when he reviews the tapes for his impersonation that he realizes how deeply he has been deceived: he will have to impersonate one of the most prominent politicians in the solar system (and one with whose views Smythe deeply disagrees)—John Joseph Bonforte, leader of the Expansionist coalition, currently in opposition but with a good chance of taking power at the next general election.

Lorenzo grows tremendously as a person during the story, as he takes on not only Bonforte's appearance, but some aspects of his personality. Bonforte is literally a "good and strong" political leader, who commands deep loyalty from his aides. When the role he assumes becomes extended due to the incapacity of Bonforte (who had been kidnapped and drugged into insensibility by people believed to be linked to Bonforte's political opponents), Smythe takes on more and more of Bonforte's persona. For various reasons, the kidnapping and drugging must be kept secret. Though the politician is retrieved, he is in poor health, forcing Smythe to extend the role, even to becoming temporary Supreme Minister and fighting an election campaign. The impersonation is noticed by the Emperor, but the ruler is sympathetic and keeps mum. At the moment of victory, Bonforte dies of the aftereffects of the drug overdose, and Smythe realizes he has little choice but to assume the role for life. In a retrospective conclusion set twenty-five years later, we learn that he has been generally successful and has carried forward Bonforte's ideals to the best of his ability. Penny (Bonforte's adoring secretary; now his wife) says, "I never loved anyone else." Smythe has transformed from self-centeredness to nobility and almost literal self-sacrifice.

The central political issue in the plot is the granting of the vote to Martians in the human-dominated Solar System. Lorenzo shares the anti-Martian prejudice prevalent among large parts of Earth's population, but he is called upon to assume the persona of the most prominent advocate for Martian enfranchisement—which he does successfully. At the end of the book his former life, including the prejudice he used to hold, seem to him like things that happened to someone else.

Resemblance to other media

Critical Reaction

The noted science-fiction writer and critic James Blish was no fan of Heinlein's treatment of his first-person protagonists in a number of his novels. Writing in 1957, however, Blish says that "The only first-person narrator Heinlein has created who is a living, completely independent human being is The Great Lorenzo of Double Star. Lorenzo is complete all the way back to his childhood — the influence of his father upon what he thinks is one of the strongest motives in the story — and his growth under pressure is consistent with his character and no-one else's."

Political system

The United States is mentioned as initially having an unspecified associate status, and later obtaining full membership. In the system, the U.S. maintains full internal autonomy and is obviously a powerful voice in Empire affairs—Bonforte himself is an American. Alternate forms of government for the United States appear in other Heinlein books. In Job: a Comedy of Justice, one of the many alternative realities through which the hero apparently wanders is a history in which the US has a monarch (called "Hereditary President"). Similarly, in The Number of the Beast, the characters briefly visit an alternate universe and consult a World Almanac to find that the U.S. has had a long list of recent presidents, all named Kennedy. In The Moon Is a Harsh Mistress one of the characters suggests that the Moon's citizens set up a monarchy after they secure their independence from Earth.

The legislative power rests with a Grand Assembly, which also meets on the Moon (where the Imperial bureaucracy is also located), most members representing an area of Earth or another planet, with other members representing constituencies not tied to any geographic place; one represents space pilots, for instance, and another districtless university women. As in the British system, representatives need not live in their district or be an actual member of the non-geographical constituency. Candidates for "safe districts" are determined by the central party office. At the time depicted in the novel, extraterrestrials are not permitted to be members of the Assembly — although they may vote in elections for representatives — and Bonforte has pledged himself to remove this exclusion. An afterword makes clear that he eventually does so, though his party loses power. He later regains office.

It is somewhat questionable how a Grand Assembly of perhaps a thousand members (and thus averaging, per representative, perhaps 5,000,000-10,000,000 people) can have room for members representing such groups as space pilots and other professions. However, every political system has its quirks and Heinlein is no doubt illustrating one of this system's.

Double Star cover controversy

The cover illustration for a 1970s UK edition of Double Star (artist: Anthony Roberts) was the subject of an unlikely controversy when it was used as the basis of an entry for the 2000 Turner Prize for modern art. The artist in question, Glenn Brown, was accused by some people of plagiarism.

See also

• Look-alike

Sources

• More Issues at Hand, by James Blish, writing as William Atheling, Jr., Advent:Publishers, Inc. Chicago, 1970

References