200 most important Astronomy topics - Sykalo Eugen 2023

The Hydrogen Epoch of Reionization Array (HERA) Science Goals

The Hydrogen Epoch of Reionization Array, or HERA, is a cutting-edge radio telescope being constructed in South Africa, designed to study the early universe and the period in which the first stars and galaxies formed. This telescope consists of a large array of radio antennas, which can detect the faint signals from neutral hydrogen gas in the early universe.

Reionization of the Universe

To understand the significance of HERA and its science goals, it is essential to first understand what reionization is. The universe was formed about 13.8 billion years ago in a Big Bang. After the Big Bang, the universe was a hot and dense soup of particles and radiation. As the universe expanded, it cooled and the particles began to clump together to form the first stars and galaxies.

Around 400,000 years after the Big Bang, the universe had cooled enough for atoms to form. At this point, the universe was filled with a sea of neutral hydrogen gas. However, over time, the ultraviolet radiation from the first stars and galaxies began to ionize this gas, stripping electrons from the hydrogen atoms. This process is called reionization.

Reionization marked a crucial period in the history of the universe, because it symbolized the transition from the "Dark Ages" to the "Cosmic Dawn". During this time, the first stars and galaxies began to shine, and the universe became transparent to light.

Science Goals of HERA

HERA is designed to study the period of reionization in detail. One of the primary goals of HERA is to understand how and when the first stars and galaxies were formed. By studying the distribution of neutral hydrogen gas during this period, astronomers can learn about the processes that led to the formation of the first structures in the universe.

Another major objective of HERA is to study the nature of dark matter and dark energy. Dark matter is a hypothetical substance that makes up about 27% of the universe, while dark energy makes up about 68%. These substances cannot be directly observed, but their effects on the universe can be detected. HERA will be used to study the large-scale structure of the universe, which can provide clues about the nature of dark matter and dark energy.

The precise measurements taken by HERA will also provide insight into the fluctuations in the cosmic microwave background radiation, which is the afterglow of the Big Bang. As a result, HERA will aid in the determination of the universe's age, composition, and expansion rate.

HERA's Capabilities

HERA is a groundbreaking telescope that is equipped with cutting-edge technology, including a highly sensitive array of antennas that can detect faint signals from neutral hydrogen gas in the early universe. These signals can provide astronomers with a wealth of information about the formation and evolution of the universe.

HERA's large array of radio antennas will enable astronomers to map the distribution of neutral hydrogen gas in the early universe with unprecedented detail and accuracy. This will enable astronomers to determine the properties of the first stars and galaxies, including their size, shape, and brightness.

HERA will also be able to detect signals from the cosmic microwave background radiation, which is the afterglow of the Big Bang. By analyzing these signals, astronomers will be able to learn more about the composition and evolution of the universe.