The image above is somewhat similar to the neon tube panels that were popular in the 1980s. But what the photo shows is much more interesting. It’s an image of a star, and the first photograph taken by the latest instrument on the Gemini South Telescope [Gemini South]GHOST telescope for short. The image shows the full spectrum of light emitted by a star called HD 222925 with amazing accuracy.
Features of the star spotted by the GHOST telescope
“This is an exciting and significant event for astronomers around the world who rely on the Gemini South Telescope to study the universe from this exceptional vantage point in Chile,” said Jennifer Lutz, director of the Gemini Observatory.
“Once this next-generation instrument is operational, the GHOST telescope will be an essential component of astronomers’ toolbox,” she added.
The light that we can see emanating from the stars is full of hidden details that describe the features of the distant star. It may show us how a star moves by how light travels from one end of the spectrum to the other, while differences in brightness may reveal internal oscillations, which can be analyzed.
The full spectrum of the star also reveals its components, which enables us to know all kinds of things related to it, such as the age of the star and where it formed, because different elements absorb light and re-emit it differently. When astronomers look at a star’s spectrum, they can look for brighter and fainter wavelengths, and use that information to determine which elements are in the star’s atmosphere.
And you can see what the faint features, known as absorption lines, look like in the image below.
How successful is the GHOST telescope?
This technology was recently used in the Hubble telescope images of HD 222925, a strange star located about 1460 light years away. Spectroscopy revealed most of the elements seen in the star’s atmosphere, 65 massive elements – mostly heavy elements that can only form in very energetic events, such as a neutron star collision or a supernova.
This means that the star HD 222925, which is going through a very late stage of its life, may be from a cloud that was rich in these elements in the first place, resulting from the death of the stars that preceded it.
New images taken by the GHOST telescope haven’t revealed anything new about the star — until now. But the star was the instrument’s first target, and it’s the first image taken by a new telescope to check whether it’s working properly, and how well it’s working. This allows the scientists to make all the necessary initial adjustments to the instrument.
GHOST telescope operating stage
Next comes the commissioning phase, when scientists and technicians will test the GHOST telescope to make sure the device is working as intended.
Once this stage, and any other modifications, are completed, GHOST will be ready for scientific observations, likely in the first half of next year.
And that’s something to look forward to, given that GHOST took 10 years to build, and because it’s 10 times more powerful than the other major Optical GSM spectrometers. Scientists also say it is the most powerful and sensitive spectrometer of its kind.
It is expected that GHOST will be able to provide fascinating views of stars that have been identified by telescopes and other scanning devices as interesting targets, and able to observe more stars, divided into their component wavelengths, in the hope that it will reveal many hidden secrets in the Milky Way.
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