https://www.scientificamerican.com/article/how-would-we-know...
except where they are noting how helium is being allowed to escape and not being captured as was previously done by the now shut down U.S. National Helium Reserve.
nearly 6x the size of earth though, good luck trying to launch a probe off that surface
NASA has a neat "exoplanet catalog" which is about to leap in size next few years with new telescopes and techniques