Astronomers at the Center of Astronomical and Space Education in Moscow, Russia have announced an astonishing find. Among their other notable achievements, their expedition discovered a new eclipsing variable star named Grigoriev 1. Researchers have long been fascinated by this binary star system in the Pegasus constellation since its discovery. It’s all in a day’s work for the Cape’s own, longstanding community program devoted to discovering variable stars. The program, which launched in 2021, has been a resounding success. It has found a grand total of 120 variable stars so far, and Grigoriev 1 is the latest find.
A recent technical paper, onto which Grigoriev 1 released on arXiv last month, spells out those determined oath. It focuses on the unique characteristics of the star and identifies it as an Algol-type binary star. Algol-type binaries are well-known for their eclipsing nature. They are indeed very similar to their prototype member, Beta Persei, aka Algol. This groundbreaking discovery adds tremendous value to the current body of knowledge already surrounding variable stars.
Characteristics of Grigoriev 1
In 2023, Grigoriev 1 was classified as an eclipsing variable binary star, consisting of two components with a large difference in size. The cold object extends approximately 323,500 km in radius. Its companion star is about 10 times larger, about 10,000 km across. This unique size difference is what creates some of the unique properties seen during eclipses.
Of these, the behavior of Grigoriev 1 during the eclipses is especially fascinating. The Kepler observations indicate that the depth of these eclipses differs in different bands of the visible spectrum. In the g filter Grigoriev 1’s brightness decreases by 2 magnitudes. This results in its brightness drop of 6.3 magnitudes at the time of the eclipse. In the opposite direction, in the r filter, the brightness diminishes by 1.4 magnitudes or 3.6 times. These differences point to the nuanced and complicated nature of this new binary system and its potential for future study.
Recently, scientists have been interested to find that Grigoriev 1 is located specifically at the tip of the color-luminosity’ plane.
“On the ‘color-luminosity’ diagram it occupies the intermediate position between hot subdwarfs and white dwarfs, which makes it even more interesting and worth studying at professional telescopes,” – scientists
This classification suggests that Grigoriev 1 may offer insights into stellar evolution and the characteristics of different types of stars.
The Path to Discovery
In 2021, researchers joined an exciting expedition to find Grigoriev 1. This great adventure was simply a run of the mill survey, intended to find variable stars among multiple star systems. The program employs a systematic approach that’s been shown to be effective. To date, it’s resulted in the discovery of 120 variable stars.
To determine what makes Grigoriev 1 stand out, researchers used cutting-edge observational techniques and data analysis. Those light curve data for this binary star are provided by the Zwicky Transient Facility (ZTF) project. This vital information allows researchers to pursue additional necessary studies.
The discovery paper detailing Grigoriev 1 is documented on arXiv with the DOI: 10.48550/arxiv.2507.01005. This publication is an essential tool for astronomers. It allows researchers to understand the properties and effects of this new binary star.
Implications for Future Research
The implications of this discovery of Grigoriev 1 are profound for future astronomical research. As an Algol-type binary, its classification puts it in a particularly well-studied category. This remains a fertile area for new research and analysis.
The variations in brightness during eclipses provide researchers with data that can enhance their understanding of binary star systems and their dynamics. Among scientists there is an increasing interest toward the unique properties of Grigoriev 1. Along the way, they will make exciting new discoveries that will deepen our understanding of stellar evolution and classification.
