A star known to Star Trek fans as Spock’s home sun has been identified as the location of a solar system that may resemble an early version of our own.
The star is called Epsilon Eridani and it shines at a moderately bright magnitude of 3.7 in the constellation of Eridanus, which means the River. It is famous in fiction as the star around which Spock’s home planet Vulcan orbits.
The star is less than a billion years old, making it around a fifth the age of the Sun. It is also less massive, and would glow orange if seen close up.
Epsilon Eridani lies nearby on the cosmic scale of things, being just 10.5 light-years away from us. All though that’s still a heck of a distance, it does mean that astronomers have been able to learn a bit about its environment.
NASA’s Spitzer Space Telescope made observations in 2009 that astronomers interpreted as revealing a disk of fine dust and debris around the star, left over from collisions of objects left over from the formation of planets.
A scientific paper at the time also suggested there was an asteroid belt and an outer Kuiper belt of frozen bodies, resembling similar zones in our Solar System. However the findings were questioned in subsequent studies by other scientists.
Now fresh research using a telescope built into a Boeing 747 airliner has confirmed Spitzer’s identification of inner and outer disk structures.
The observatory is NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) aircraft, which carries a 2.5-meter (98-inch) telescope at the back. It is a joint project with the German Aerospace Center (DLR) and observes in a part of the spectrum of light which is sensitive to cool dust.
SOFIA hit the headlines in 2015 when Star Trek’s Lt Uhura, Nichelle Nichols, flew aboard it into the stratosphere to get as close to “the Final Frontier” as she could for real.
The latest findings about Epsilon Eridani, published online by the Astrophysical Journal, are the result of observations made from Sofia high over the Pacific on a flight on January 28, 2015, from NASA’s Armstrong Flight Research Center in Palmdale, California.
The mission to observe Epsilon Eridani was led by Kate Su, an associate astronomer at the University of Arizona and the university’s Steward Observatory, who is lead author of the newly published scientific paper.
Massimo Marengo, an associate professor of physics and astronomy at Iowa State University, was one of nine co-authors of the paper. He says the findings confirm that Epsilon Eridani is a good replica of our own early Solar System, and so can help show how the Sun’s own planets and other family members evolved.
The team had to spend years carrying out computer modelling to help determine the structure of the disk around Epsilon Eridani.
Marengo said in a summary of the project: ““This star hosts a planetary system currently undergoing the same cataclysmic processes that happened to the Solar System in its youth, at the time in which the Moon gained most of its craters, Earth acquired the water in its oceans, and the conditions favorable for life on our planet were set.
“But we can now say with great confidence that there is a separation between the star’s inner and outer belts. There is a gap most likely created by planets. We haven’t detected them yet, but I would be surprised if they are not there.
“Seeing them will require using the next-generation instrumentation, perhaps NASA’s 6.5-meter James Webb Space Telescope scheduled for launch in October 2018.”
Marengo added: “The prize at the end of this road is to understand the true structure of Epsilon Eridani’s out-of-this-world disk, and its interactions with the cohort of planets likely inhabiting its system.
“SOFIA, by its unique ability of capturing infrared light in the dry stratospheric sky, is the closest we have to a time machine, revealing a glimpse of Earth’s ancient past by observing the present of a nearby young Sun.”
Another nearby star that can be seen with the unaided eye and has a planetary system is Tau Ceti, which we have written about before.
By the way, if you want to see Epsilon Eridani for yourself, now is not the best time as the Sun currently lies close by in the sky. It will be back on view later in the northern autumn (fall) and winter.