AI made image of a quasar

What Are Quasars?

Quasars, short for « quasi-stellar objects, » are among the most fascinating phenomena in the universe. These extremely bright and distant celestial objects are powered by supermassive black holes at the centers of galaxies. Despite their small physical size, quasars can outshine entire galaxies.

How Do Quasars Form?

At a quasar’s core is a supermassive black hole, with a mass millions or billions of times that of the Sun. When matter falls into its gravitational pull, it forms a hot, glowing accretion disk. As this material spirals inward, it emits vast radiation—from visible light to X-rays—making quasars observable from billions of light-years away.

The Power of Quasars

Quasars release more energy than the rest of their host galaxy combined. This power comes from material falling into the black hole and heating up. Many quasars also emit jets of particles moving near light speed, which can extend for thousands of light-years. These jets are often detected as radio waves or X-rays and are thought to be shaped by strong magnetic fields.

Why Are Quasars Important?

Quasars help scientists study the early universe. Since their light takes billions of years to reach us, observing quasars is like looking back in time—about 10 to 12 billion years. They offer clues about galaxy formation and black hole evolution.

The Search for Quasars

Quasars are hard to find due to their faintness and great distance. However, large sky surveys like the Sloan Digital Sky Survey (SDSS) help astronomers locate and study them in detail.

The Mystery of Quasars

While we understand how quasars shine, questions remain—especially about how black holes grow and how jets form. The connection between quasars and their host galaxies is also not fully understood.

Conclusion

Quasars are spectacular cosmic engines powered by black holes. Studying them reveals crucial information about the universe’s early days and the forces shaping galaxies. As technology improves, quasars will continue to be a window into the distant past.

Miquel Pinyol 2-4