An analysis of the new data from Gaia showed that the Kaffau star (SDSS J102915 + 172927), considered one of the oldest in the Milky Way, is of the dwarf type. This is a weak object with an age of 13 billion years, living in the territory of Leo. In 2011, Elisabetta Kaffau found out that the star is almost entirely composed of hydrogen and helium, and also has an extremely low content of heavier elements. This chemical composition surprised scientists, because the low mass (0.8 solar) and the low level of metals (20,000 times less than that of the Sun) suggested that the object should not exist at all.
The absolute value of SDSS J102915 + 172927 obtained from Gaia parallax implies that we have a dwarf star The star was investigated for a long time, but many of its properties remained mysterious. One of the scenarios suggested that it was a dwarf distant by 4,400 light years, and the other insisted that we were in front of a subgiant living at a distance of 20,200 light years.
New information from Gaia provided important information to characterize the object. Now the exact distance is 1.37 + 0.15-012 kiloparsecs. The analysis also excluded the variant with subgiant and confirmed the dwarf nature. In addition, they also crossed out the assumption that the star appeared from the environment, mainly enriched with supernova Ia-type.
