The participants of the APPLAUSE project published the final part of the archive of photographic plates with negatives of the night sky on the global network. It includes 125,473 scans of 97,703 photos. The work on their digitization took ten years.
The APPLAUSE project was created with the aim of cataloging old astronomical photographs from the archives of various observatories taken between 1893 and 1998. The researchers digitized the images with the date, the sky area and the shooting location. In addition, the project participants have developed software based on artificial intelligence technologies to remove defects on plates caused by scratches or dust, as well as calibration. This made it possible to compare them with each other for scientific purposes.
Digitization of old photographic plates is very important for astronomers. It allows them to trace the movement of stars and estimate the change in their intensity over several decades. They can also be used to study other celestial bodies.
As an example, the star HD49798. In the 1960s, researchers noticed fluctuations in its brightness, but only recently they were able to conduct a detailed analysis of them. It showed that since the mid-1960s, the star has constantly increased its intensity, and then began to shine less brightly. In addition, there were rapid changes in its glitz, lasting only a few days.
In 1999, satellite data showed that HD49798 emits X-rays. Today, astronomers suspect that their source is its invisible companion, most likely a neutron star. Until recently, scientists could not track long-term changes in the intensity of the system because they did not have data spanning several decades. But thanks to the publication of the APPLAUSE archive, they got the opportunity to look into the past of this couple.
According to https://phys.org
Follow us on Twitter to get the most interesting space news in time