European astronomers have managed to find a new double star in the center of the planetary nebula M 3-1. Nakhodka interested in its unusually short orbital period of just over 3 hours. Because of this, he becomes the owner of one of the shortest orbital overflights among the double central stars recorded today.
Twin central stars are important for developing our knowledge of the formation and evolution of planetary nebulae. For astronomers, such objects with short orbital periods are especially valuable because they improve the understanding of such processes. Moreover, finding new examples allows us to realize the nature of the phase itself after the general state.
Archival images M 3-1 showing amazing threadlike waist and elongated reactive structures
Scientists from the Institute of Astrophysics in the Canary Islands conducted a long-term monitoring campaign in search of nearby binary stars using photometric variability. For the observations, the Very Large Telescope (VLT) and the New Technological Telescope (NTT) were used. Planetary nebula M 3-1 was one of the campaign targets. Observations of it showed the presence of a central star system with apparent variability of the short orbital period and visible primary and secondary eclipses. At an effective temperature of 48000 K, the primary star in a radius covers 0.41 solar, and in mass - 0.65. The secondary one is cooler and less massive: 5000-12000 K, with a radius of 0.28 solar and a mass of 0.17.
The rotation period of the system covers 3 hours and 5 minutes, which puts it in a record place among similar objects. The researchers note that both stars were extremely close to filling Roche Cavity. This indicates a possible merger in the future. The analysis reports that the event may occur in 1.5 billion years. For a better limitation of the parameters of the objects, as well as an understanding of the formation and evolution, further chemical and morpho-kinematic studies of the M 3-1 nebula will be needed.