It is a gas giant, with dimensions and time of revolution comparable to Jupiter, and until a few years ago it was the closest exoplanet to us. Precisely on this record, NASA, proposing a beautiful artistic representation as the “Image of the day” on its website, ran into a small oversight, now corrected
Anyone who happened to be on the NASA web page this morning will have been a bit dumbfounded. In fact , an artistic representation of a gas giant with the title “Nearest Exoplanet to Our Solar System” stood out in plain sight in the box dedicated to the “Image of the day”.
The image is indeed very impressive. Signed by Greg Bacon of the Space Telescope Science Institute, it dates back to at least 2006 and depicts how the gas giant Epsilon Eridani b could be : an exoplanet of mass comparable to that of Jupiter orbiting a very young star – Epsilon Eridani, just 800 million years of age – 10.5 light years from us. Precisely by virtue of its tender age, Epsilon Eridani is still surrounded by a disk of dust – here represented by an oblique and greyish line – which extends for over 30 billion km. The rings and satellites surrounding the planet are purely hypothetical but plausible, explains the accompanying text. Not failing to underline how – although the planet itself, as a gas giant, is hardly compatible with life as we know it – its eventual moons could instead present conditions suitable for life.
To leave visitors baffled, we said, however, would have been the statement on its record of proximity : it is the closest known exoplanet to our solar system , the text said. But no, it is not the closest known exoplanet, not anymore . And its orbit is also not as eccentric as previously thought.
«The existence of Epsilon Eridani b has been well known for 20 years now. The latest update on the system architecture, a couple of years ago, found the planet in a practically circular orbit, no longer as eccentric as the first measurements seemed to indicate. And obviously in the meantime Epsilon Eridani b has climbed into second position as the closest exoplanet to the Sun, given that since 2016 the record belongs to Proxima b, and there are no closest stars “, Alessandro Sozzetti , astronomer at INAF reminds Media Inaf of Turin and expert on exoplanets.
In short, if you are among those who have found themselves displaced, know that you were right: for once it was NASA that made a mistake. A few minutes ago the error was corrected (the title still not), the news was removed from the home page and the text now reports that Epsilon Eridani b was – it was – the closest exoplanet to the Solar System. However, to this day it remains the closest extrasolar gas giant to us.
Featured image: Artist’s impression of Epsilon Eridani b. Image Credits: Nasa, Esa and G. Bacon (Stsci)
Provided by INAF