Intelligent alien life could intercept human transmission into space sooner than we thought, scientists say

Findings add to ability of astronomers to look for signs of technology-use outside Solar System

An extraterrestrial alien civilisation could likely intercept transmissions from Earth within the next 100 years, a new study has revealed.

The likelihood of transmissions from Nasa’s Deep Space Network (DSN) to one of the agency’s space exploration probes being intercepted by an advanced alien civilisation was examined in the yet-to-be peer-reviewed research, posted as a preprint in open access archive arXiv.

These spacecraft include the Voyager 1, Voyager 2, Pioneer 10, Pioneer 11 and New Horizons, according to researchers from the University of California, Los Angeles (UCLA) and the University of California, Berkeley.

Scientists hoped to expand upon an earlier study which determined the stars outside our Solar System that these probes – except the New Horizons – would pass over the next few million years.

Researchers then expanded on the analysis to identify which stars outside the Solar System will encounter the signal transmissions from Earth – traveling at the speed of light to these interstellar spacecraft.

They listed in the research the identity and features of these stars, their distance from Earth, as well as the year they will likely be contacted by the transmitted signals and the year we will expect a return transmission.

The planets surrounding these encountered stars will also encounter the spacecraft’s transmissions, the study noted.

Based on this, scientists then estimated the year when potential intelligent alien civilizations around these stars could likely intercept these transmissions from Earth and when we might hear a response, provided they reply instantaneously.

The total number of such stars identified by scientists increased at a very low rate through 2100, and then at an increasingly greater rate later.

“This shows that the majority of the encountered stars are at relatively large distances from Earth as it takes DSN transmissions longer to encounter them. This increase in stars contacted over time is consistent with the increasing volume covered by the transmissions over time,” researchers explained in the study.

“Our results include 5 total stars for which we could expect returned transmissions within the 21st century, and 7 total stars for which we could expect returned transmissions within the next 100 years,” study co-author Reilly Derrick told Universe Today.

The five stars from which scientists expect a potential reply by the end of this century are within 50 light years from Earth, and two other stars from which there could likely be a reply within the next 100 years are located at a distance of 73 light-years from our planet.

Researchers believe the new findings add to the recently acquired ability of astronomers to look for signs of technology use, or a technosphere, around planets outside our Solar System.

“In the prioritisation of stars in the sky to search for technosignatures, we provide a list of targets that have or will receive transmissions from the DSN that were targeted at our own interplanetary spacecraft,” scientists wrote in the study.

This catalogue of stars developed in the study provides a window for further studies to plan their observations, they said.