Lucky Starr and the Big Sun of Mercury

Lore & Background

The novel was written in 1955, when it was believed that Mercury was tidally locked to the Sun (though it is now known that Mercury is not tidally locked, so no side is permanently dark). A character notes that there are places on Mercury's sunside where it is hot enough to melt lead and boil sulfur, while the nightside is the only planetary surface in the Solar System that never sees the Sun. Most of the novel's action takes place in and around an astronomical observatory located at the planet's north pole, where libration results in a half-mile movement of the terminator. The observatory was built fifty years before on the site of a mining complex, which has since been abandoned.

It has been a year since the events in Lucky Starr and the Oceans of Venus, and in this novel, the Sirians are not described as using positronic robots as slaves, and there is no Sirian robot driven by solar radiation to ignore the Three Laws of Robotics.

Reader's Guide

Lucky Starr and the Big Sun of Mercury is significant as the fourth entry in Asimov's juvenile series, notable for its depiction of a tidally locked Mercury—a scientific view later rendered inaccurate. The novel introduces detailed descriptions of the Sirians, who had been a vague menace in earlier books; here they are portrayed as a race-conscious, robot-using aristocracy that despises Earthmen. The story also features positronic robots and the Three Laws of Robotics, marking a point where Asimov no longer attempted to disguise his authorship, though the novel still appeared under the pseudonym Paul French. The plot revolves around sabotage at a polar observatory and a Sirian robot driven by solar radiation to ignore the Three Laws. The novel's legacy includes its reflection of mid-1950s astronomical knowledge and its role in expanding the Lucky Starr universe's themes of political intrigue and scientific progress.

Did You Know?

• The novel was written in 1955, when Mercury was believed to be tidally locked to the Sun.
• Since 1972, reprints have included a foreword by Asimov noting that advancing knowledge of Mercury has rendered some descriptions inaccurate.
• The Sirians in this novel are described as race-conscious, breeding themselves into uniformity, and using positronic robots as slaves.
• The novel features a Sirian robot driven by solar radiation to forego the Three Laws of Robotics.

The Pen Name Behind the Pages

The Lucky Starr series, which includes the novel The Big Sun of Mercury, was crafted by Isaac Asimov — the American writer and biochemistry professor at Boston University — under the pseudonym Paul French. This choice of a pen name deliberately distinguished the juvenile science-fiction novels from Asimov's extensive body of adult-oriented work. While Asimov was widely recognized during his lifetime as one of the "Big Three" science fiction writers alongside Robert A. Heinlein and Arthur C. Clarke, the Lucky Starr books reached a younger readership through this alternate identity. Readers who encountered the series likely met "Paul French" as the author's name, unaware that the mind behind those stories was the same man responsible for the Foundation series, the Robot series, and hundreds of other works. The use of a pseudonym for juvenile fiction served as a deliberate separation of audience and brand within an already enormous literary output, allowing the science-fiction adventures to stand in their own right for young readers.

A Thread in an Enormous Tapestry

Asimov wrote or edited more than five hundred books and an estimated ninety thousand letters and postcards during his lifetime, and the Lucky Starr series of juvenile science-fiction novels represents one strand in that vast creative web. Beyond long-form novels, he produced more than three hundred and eighty short stories, including "Nightfall," which in 1964 was voted the best short science fiction story of all time by the Science Fiction Writers of America. His published work spanned nine of the ten categories in the Dewey decimal classification system, touching on chemistry, astronomy, mathematics, history, literary criticism, and even guides to the Bible and Shakespeare. The Lucky Starr books, including The Big Sun of Mercury, sit within this extraordinary range as accessible science fiction aimed at younger readers, complementing his more technically demanding hard science fiction novels and his popular science volumes such as Guide to Science and the three-volume Understanding Physics.

The Science-Fiction Tradition

The Lucky Starr series emerged from a science fiction tradition in which Asimov was a defining figure. Best known for his hard science fiction, he was grouped with Robert A. Heinlein and Arthur C. Clarke as the "Big Three" of the genre during his lifetime. His most celebrated works include the Foundation series about a fallen space empire, whose first three books won a one-time Hugo Award for "Best All-Time Series" in 1966, as well as the Galactic Empire and Robot series, which he later unified into a single "future history" with Foundation and Earth in 1986. The juvenile novels of the Lucky Starr cycle, penned as Paul French, carried forward the same scientific imagination into stories designed for younger readers. Asimov's popular science books often explained concepts historically, tracing ideas back to their simplest origins, and this pedagogical sensibility likely informed the way science was presented within the Lucky Starr adventures, including The Big Sun of Mercury.

Recognition and Lasting Footprint

Asimov's influence extended well beyond the pages of his novels. He served as president of the American Humanist Association and held a professorship in biochemistry at Boston University, grounding his speculative fiction in genuine scientific literacy. Several entities bear his name in permanent tribute: the asteroid (5020) Asimov, a crater on Mars, a Brooklyn elementary school, Honda's humanoid robot ASIMO, and four literary awards. The Lucky Starr series, including The Big Sun of Mercury, contributed to the body of work that earned these honors, even as it circulated under the Paul French byline. Asimov's early life in Brooklyn, where his family ran candy stores that sold newspapers and pulp magazines, shaped his lifelong love of the written word; he taught himself to read at age five and was devouring science fiction magazines by nine. That insatiable curiosity, carried into a career spanning nine Dewey categories, is the engine behind every book in the Lucky Starr cycle.