Stellar Catalog | Discover the nearby universe

Stars are enormous spheres of hot gas that shine by generating energy through nuclear fusion in their cores. Most stars are made primarily of hydrogen and helium. In the center of a star, intense pressure and temperature cause hydrogen atoms to fuse into helium, releasing a tremendous amount of energy as light and heat.

Stars vary widely in size, color, and brightness. Some are small and cool, like red dwarfs, while others are massive and extremely hot, like blue giants. Each star follows a life cycle — forming from clouds of gas, shining for millions or even billions of years, and eventually ending its life in different ways depending on its mass. The Stellar Catalog currently includes nearly 10,000 stellar systems, with a focus on stars located within 100 light-years of Earth.

Star position

The position of a star tells us where it appears in the sky, similar to how we use coordinates like latitude and longitude on Earth. In astronomy, the three main coordinates are right ascension, declination and distance.
Star position

Star luminosity

Luminosity is the total amount of energy a star gives off every second. Think of it as the star’s true brightness — not just how bright it looks from Earth. This is important because some stars may appear dim simply because they are far away, not because they’re actually faint.
Star luminosity

Star temperature

The temperature of a star refers to the temperature at its surface, also called the photosphere. It is measured in kelvins (K), the standard unit for temperature in astronomy. A star’s temperature tells us a lot about its physical properties and where it stands in its evolutionary stage.
Star temperature

Star mass

The mass of a star is the total amount of matter it contains. It is one of the most important properties of a star, as it determines almost everything about how the star lives, changes, and dies. In astronomy, star mass is usually measured in solar masses (M☉) — where 1 solar mass is equal to the mass of our Sun.
Star mass

Star size

The size of a star refers to its radius — the distance from its center to its surface. Star size is usually measured in solar radii (R☉), where 1 solar radius equals approximately 696,000 kilometers. Depending on their type and life stage, stars can be much smaller or larger than the Sun.
Star size

Star age