Researchers have been continuously trying to send messages to extraterrestrial beings for decades, yet without success.
The question of whether extraterrestrial life exists somewhere in the universe has captivated humanity for centuries. Since the 1960s, the scientific community has been persistently working to detect signals from advanced civilizations. As part of the global project “Search for Extraterrestrial Intelligence” (SETI), researchers utilize radio telescopes to scan the skies for unusual signals that might unveil traces of alien life. In addition to radio signals, they are also considering the search for signs of advanced technology, such as megastructures, atmospheric pollution, or strange energy emissions, which could provide compelling evidence of intelligent life beyond Earth. Furthermore, researchers are also attempting to send messages to extraterrestrial beings through various projects, according to Amusing Planet.
The Morse Message was one of the first radio signals aimed at interstellar intelligence. The message included the three letters MIR (meaning “peace” and “world” in Russian), LENIN, and USSR, encoded in Morse code and transmitted to Venus in 1962, from the newly constructed Evpatoria Planetary Radar (EPR) complex in Crimea. The transmission was divided into two parts. The first message “MIR” was sent on November 19, 1962, and the second message containing LENIN and USSR was transmitted on November 24, 1962. Both signals reflected off the surface of Venus and were received back on Earth after 4.5 minutes. Based on Venus’s position in November 1962, the message has since traveled across the universe towards the constellation Libra.
The Gold-Plated Plaque on Pioneer Spacecraft
Attached to the exterior of the Pioneer 10 and Pioneer 11 spacecraft are a pair of gold-anodized aluminum plaques conveying a message in the form of images. The plaques depict a man and woman alongside various symbols designed to provide information about the spacecraft’s origin. These include representations of the intricate structure of hydrogen, the most abundant element in the universe, a star map with the Sun at the center showing the relative distances of 14 pulsars, and a binary code indicating their periodicity, which helps determine the launch period. Additionally, there is a silhouette of the Pioneer spacecraft positioned behind an image of a human figure, allowing for an estimation of human size through spacecraft measurements, and an outline of the Solar System with a long arrow pointing to Earth as the planet that launched the spacecraft.
Pioneer 10 was launched in 1972. It flew past Jupiter in 1973, crossed the orbit of Saturn in 1976, Uranus in 1973, and Neptune in 1983. The last successful communication with the spacecraft occurred in 2002 when Pioneer 10 was 12 billion kilometers from Earth. Currently, the spacecraft is heading towards the star Aldebaran, located 65 light-years away in the constellation Taurus.
Pioneer 11 was launched in 1973, flew past Jupiter in 1974, and Saturn in 1979. The probe exhausted its power and ceased operations in 1995, losing communication. At that time, it was 16.6 billion kilometers from Earth. The spacecraft is heading towards the constellation Aquila, where it is expected to fly near a star in about 4 million years.
The Arecibo Message
The Arecibo Message was transmitted into space from the Arecibo Observatory in Puerto Rico on November 16, 1974. The message consists of a series of characters and graphics encoded in binary, aimed at the current location of the globular cluster M13, approximately 25,000 light-years from Earth. Assuming extraterrestrial beings could decode it correctly, the 1,679 bits of data would reveal numbers from 1 to 10, the atomic numbers of the elements hydrogen, carbon, nitrogen, oxygen, and phosphorus that make up DNA, the chemical formula for nucleotides, the estimated number of nucleotides in the human genome, a graphic representation of the double helix structure of DNA, the average human size, the shape of a human, and the Earth’s population of around 4 billion at that time. Additionally, the data contains a graphic of the Solar System (including Pluto), an illustration of the Arecibo radio telescope, and the size of the transmitting antenna disk.
The Golden Record on Voyager
The Golden Record on the Voyager spacecraft. (Photo: WFMT).
When Voyager 1 and 2 were launched in 1977, each spacecraft carried an identical gold-plated record containing a curated collection of sounds and images selected to illustrate the diversity of life and culture on Earth. Each record is intended for any intelligent extraterrestrial beings that may find it. The Golden Record contains 116 images depicting various objects from the Solar System, plants, animals, humans, and architecture. It also includes recordings of greetings in 55 ancient and modern languages, as well as various human sounds such as laughter and footsteps. Additionally, the record features music by Bach, Mozart, Beethoven, and many other composers, along with a quick guide on how to play the record and interpret the images.
Voyager 1 passed the orbit of Pluto in 1990 and left the Solar System in 2004. In about 40,000 years, Voyager 1 will head towards the star Gliese 445 in the constellation Camelopardalis, while Voyager 2 will approach the star Ross 248 in the constellation Andromeda, which is 1.8 light-years away.
The Cosmic Call Message
In 1999 and 2003, two sets of interstellar radio messages were sent from Yevpatoria, Ukraine, targeting a system of 9 stars. The messages included special symbols designed to represent various basic data such as alphabets, mathematical calculations, units of measurement, names of planets, chemical elements, physical concepts, and biology. The messages were transmitted multiple times. The nearest star targeted by the project is Gliese 49 located in the constellation Cassiopeia, approximately 32 light-years from Earth. The farthest star is 16 Cygni, a system of 3 stars located 69 light-years away in the constellation Cygnus.
