Observations from NASA’s James Webb Space Telescope of Earendel – the farthest star ever detected – reveal a massive B-type star that is more than twice as hot as our sun and a million times more luminous.
The star in the very distant universe, and a billion years after the big bang, was captured by the observatory’s Near-InfraRed Camera instrument.
NASA said that Earendel – which means “morning star” in Old English and is, perhaps, a familiar-sounding name to fans of “The Lord of the Rings” trilogy – is located in the Sunrise Arc galaxy.
It is detectable only due to a combination of technology and gravitational lensing. Gravitational lensing occurs when a celestial object like the foreground galaxy cluster has such a massive gravitational pull that it warps time and space around it.
Scientists using Webb and the Hubble Space Telescope – which first discovered the star – were able to detect Earendel because of its alignment behind a wrinkle in space-time created by the massive galaxy cluster WHL0137-08.
The galaxy cluster, located between Earth and the star, is so massive that it warps the fabric of space, producing a magnifying effect that allows astronomers to look through it.
Earendel only appears as a single point of light, while other features in the galaxy appear multiple times because of this effect.
Due to this, scientists have determined the object is magnified by a factor of at least 4,000 and is extremely small.
Due to the color of Earendel, astronomers also believe they can see hints of a cooler, redder companion star. The light, NASA notes, has been stretched by the universe’s expansion to wavelengths longer than the Hubble Space Telescope can detect.
While stars as massive as Earendel often have companions, researchers did not expect Webb to reveal any such stars because they would be so close together and indistinguishable on the sky.
NIRCam also shows other notable features in the Sunrise Arc: the most highly magnified galaxy yet detected in the universe’s first billion years. Those include young star-forming regions and older star clusters as small as just 10 light-years across. On either side of the wrinkle of maximum magnification that runs through Earendel, the features are mirrored by the distortion of the gravitational lens, with the star-forming region appearing elongated and smaller dots on either side of Earendel are two images of one older, more established star cluster. The cluster, which is estimated to be at least 10 million years old, is gravitationally bound and likely to persist until the present day.
NASA says data analysis from Webb’s Near-Infrared Spectrograph instrument observations of the Sunrise Arc galaxy and Earendel is underway, which will provide precise composition and distance measurements for the galaxy.