Telescope Capture at Grasslands Observatory
Credit: Tim Hunter et al. (2025)
A long-lost star, discovered by the legendary astronomer Edward Emerson Barnard in 1892, has been astonishingly rediscovered in its original location.
Barnard was not just any astronomer; he made significant contributions to the field, including the discovery of Jupiter’s fifth moon, Amalthea, in 1892—nearly three centuries after Galileo’s initial discoveries. Recently, his observations have gained renewed interest due to a puzzling article he published in 1906, titled “Unexplained Observations.”
On a particular morning, Barnard noted a star near Venus while using his telescope to search for its satellite. He estimated its brightness to be around 7th magnitude on the astronomical scale, where fainter objects bear higher numbers. Typically, under dark skies, stars of magnitude 6 are the faintest visible to the human eye.
Beneath the stars at the Bonner Cathedral, which cataloged all stars brighter than magnitude 9.5, Barnard’s 7th magnitude star was conspicuously absent. Instead, the only celestial body he found nearby was a significantly dimmer 11th magnitude star—about 100 times less bright.
Could it have been a large asteroid? “Ceres, Pallas, Juno, and Vesta were elsewhere,” he surmised. Some theorized that the 11th magnitude star he eventually observed in that region might have temporarily brightened. Other scientists speculated that Barnard could have been deceived by a “ghost” image of Venus through the telescope. The mystery lingered until late December 2024 when a dedicated group of astronomers sought to unravel it.
“In a weekly Zoom meeting dubbed ‘Asteroid Lunch,’ I brought it up,” says Tim Hunter.
Hunter, an Arizona-based amateur astronomer and co-founder of the International Dark Sky Association, along with both amateur and professional astronomers, evaluated all previous hypotheses and found flaws in them.
As doubts began to consume the group, Roger Ceragioli, an optical engineer from the University of Arizona, revisited the ghost theory by observing Venus at dawn using a vintage telescope similar to Barnard’s. Much to his surprise, although Venus was not positioned where Barnard had seen it, “the star emerged clearly in my field of view,” he noted. This led him to theorize that the star must be bright enough to be visible at dawn, even though the star map revealed it to be only 8th magnitude and therefore relatively faint.
The group’s conclusive findings suggested that Barnard’s purported 7th magnitude star was indeed the 11th magnitude star noted later—appearing brighter due to the dawn light. Using a 36-inch telescope at the Lick Observatory in California, Barnard first spotted this star alongside Venus, but no equally bright stars were visible in the area.
Understanding Star brightness measurement was a specialized skill in Barnard’s era. It had only been refined by astronomers focusing on variable stars, which Barnard had not formally studied. Thus, his mistake was rather excusable, as Ceragioli suggests.
Hunter affirms Barnard’s legacy remains intact, saying, “We’re all big fans of Barnard. It’s a minor error in an impressive career.”
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Source: www.newscientist.com
