The picture of the Very Large Array Radio Telescope in New Mexico, the United States, in the film is real. The telescope had been working and collecting data.
The role model of Kent Clark is Dr. Kent Callus.
The role of Dr. Ai Luowei is based on two radio astronomers, Grote Reber and John Kraus.
At the climax of the film, Judy Foster performed a series of conflicting expressions. The director Robert Zemeckis asked her to shoot six times, each time showing a different expression, such as tension, joy, fear, sadness, etc., and then let the special effects staff connect each expression through modification.
The long shot of Dr. Ai Luowei walking from the parking lot to the laboratory was actually taken in two places, and in the end it was also connected by digital technology.
In the film, Little Ai Luowei's father called her Sparks, which was the nickname for spark gap transmitters used by early radio operators.
At the end of the film, Ai Luowei said "if humans were the only life in the universe it would'be a terrible waste of space", which is a famous quote by the novel author, astronomer and scientific activist Carl Sagan.
As early as 1995, Judy Foster was very interested in the film, but initially refused to star in it. Later, when she saw the revised script, she regained her impulse to act.
The original director of the film was George Miller, but then Warner Bros. authorized him to direct "Mad Max 2" and "Mad Max 3", and Robert Zemigis took over the film.
Francis Ford Coppola has accused the original author of the film, Carl Sagan, of breach of contract. According to Coppola, the original "Overtime Contact" was created for Zoetrope Studios and may be filmed as a children’s TV show. Grid must pay US$250,000 to publish or make a film.
The satellite dish at the beginning of the film is actually the Arecibo radio telescope in Puerto Rico.
The code name of "Project Argos" comes from the Hundred Eyes Giant in Greek mythology.
The eyes of Gina Malone, who played little Ellie in the film, are brown. In order to match the color of Judy Foster's eyes, the crew used a computer to change Gina Malone's eyes to blue.
The press conference where President Clinton spoke was re-edited and caused controversy. Later, the CNN logo was banned from appearing in the feature film.
A long shot of Ellie in the mirror running up the stairs to fetch medicine in her childhood is impossible to complete in reality. At that time, it was done with the help of a blue screen.
CNN participated in the filming of the film, and 25 CNN journalists appeared in world news reporting the sensational effects of signals from outer space.
Drujan, the wife of the original author of the novel, Carl Sagan, also played a guest role in the film.
