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We Are Not Alone: An Earth-like Planet Spotted Orbiting The Sun’s Closest Star

A third planet has been discovered by astronomers orbiting Proxima Centauri, which is the star closest to the Sun. This third planet is named “Proxima Centauri d”. This new planet is probably smaller than planet Earth. Proxima Centauri d possibly has oceans and oceans of liquid water.

Guillem Anglada-Escudé who works as an astronomer at the Institute of Space Sciences in Barcelona, Spain, stated “it’s showing that the nearest star probably has a rich planetary system.” Anglada-Escudé organized a team that in 2016 discovered the first planet seen orbiting Proxima Centauri.

Joāo Faria and his associate astronomers detected Proxima Centauri d from “measuring tiny shifts in the spectrum of light from the star as the planet’s gravity pulled at it during orbit.” This team used Echelle Spectrograph for Rocky Exoplanets and Stable Spectroscopic Observations (ESPRESSO), which is an extremely large telescope, a system of four 8.2 metre telescopes at the European Southern Observatory in Cerros Paranal, Chile. They recently published their findings in Astronomy & Astrophysics.

The astronomers used a “wobble” technique that looks for “changes in the star’s motion along the line of sight from Earth.” The ESPRESSO detects variations at 10 centimeres per second. Faria says the planet’s orbit around the Sun takes 5 days and moves at about 40 centimetres per second. Faria said he knew what the ESPRESSO could do, but he was still very surprised to see the planet showing up.

Faria’ s team observed Proxima Centauri’s spectrum over 100 times in two years. The team keeps the ESPRESSO in a special observatory room inside a tank that keeps its pressure and temperature constant. By keeping the ESPRESSO in this type of space ensures that the system’s measurements are consistent and repeatable over years. According to Faria, ESPRESSO can “measure the wavelength of spectral lines with a precision of 10−5 ångströms, or one-ten-thousandth of the diameter of a hydrogen atom.”

Currently, Proxima Centauri d is not designated as a full planet but is designated as a “planet candidate.” These astronomers are waiting for independent confirmation before officially introducing an entire new world to the world. But Faria’s team have confidence in their findings. Faria’s team provide that based on the “effects on the star’s spectrum… the planet is probably smaller than Earth, but no less than 36% of our planet’s mass.”

The ESPRESSO system was created to search for extrasolar planets and to study light from bright but distant objects called quasars.

Anglada-Escudé provided that the most exciting thing about this discovery is that the ESPRESSO works as advertised. Specifically he said, “ESPRESSO is the new instrument which everyone wants to use and play with.”

Proxima Centauri being the closest star to the Earth has a special place in astronomers heart because as Anglada-Escudé says, “it always has a little bit of mystique, being the closest one.”

Elisa Quintana, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland added, “it is fascinating to know that our Sun’s nearest stellar neighbour is the host to three small planets… their proximity make this a prime system for further study, to understand their nature and how they likely formed.”

Even though as of today, interstellar travel is in the realm of science fiction, Faria admits that “it does make you wonder.”

One day the science fiction of interstellar travel could become an everyday occurrence. And who knows who we will meet when we get there.


La Shon Y. Fleming Bruce a/k/a SHONSPEAKS is a blogger, speaker, and lead creator of I am also a lawyer and managing member of The Fleming-Bruce Law Firm, P.L.L.C. If you want to check out more of my writings that may not be released on this site, go over to my website at




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