200 most important Astronomy topics - Sykalo Eugen 2023

The Dark Energy Spectroscopic Instrument (DESI)

The Dark Energy Spectroscopic Instrument (DESI) is a new instrument designed to study dark energy, the mysterious force that is believed to cause the accelerated expansion of the universe. DESI is a collaborative project between multiple institutions, including the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab), the University of California, Berkeley, and the University of Arizona.

What is DESI?

DESI is a powerful new instrument that combines state-of-the-art robotics, fiber-optic cables, and spectrographs to measure the properties of galaxies and quasars. It is designed to observe the light emitted by millions of galaxies and quasars over a five-year period, creating a 3D map of the universe that will help astronomers better understand dark energy.

One of the unique features of DESI is its use of robotic arms to position 5,000 fiber-optic cables on the surface of a telescope. Each fiber-optic cable is pointed at a different galaxy or quasar, allowing DESI to observe the light emitted by each object. The light is then analyzed by a series of spectrographs, which break the light into its component colors. By analyzing the colors of light emitted by each galaxy or quasar, astronomers can determine the object's distance and motion.

DESI's unprecedented ability to observe and measure the properties of millions of galaxies and quasars will allow astronomers to create a detailed 3D map of the universe that will provide valuable insights into the nature of dark energy. By studying the distribution of galaxies and quasars, DESI will help astronomers determine how dark energy has affected the expansion of the universe over time.

In addition to its scientific goals, DESI is also an important example of collaboration between multiple institutions. The project involves researchers from the Department of Energy's Lawrence Berkeley National Laboratory, the University of California, Berkeley, and the University of Arizona, among others. This collaborative effort has enabled the development of a cutting-edge instrument that will help answer some of the most fundamental questions about the universe.

How does DESI work?

DESI is an innovative instrument that combines state-of-the-art robotics, fiber-optic cables, and spectrographs to measure the properties of galaxies and quasars. The process starts with a series of robotic arms that position 5,000 fiber-optic cables on the surface of a telescope. Each fiber-optic cable is precisely pointed at a different galaxy or quasar, allowing DESI to observe the light emitted by each object. The robotic arms are controlled by a sophisticated computer system that ensures that each fiber-optic cable is accurately positioned to within a few microns.

Once the light from each galaxy or quasar has been collected by the fiber-optic cables, it is directed to a series of spectrographs. These spectrographs are highly sensitive instruments that can break the light into its component colors. By analyzing the colors of light emitted by each galaxy or quasar, astronomers can determine the object's distance and motion. This allows them to create a detailed 3D map of the universe that shows the distribution of galaxies and quasars.

DESI's use of spectroscopy is an important innovation that sets it apart from previous instruments used to study dark energy. Unlike previous instruments, which were only able to observe a small number of objects at a time, DESI is capable of observing millions of galaxies and quasars over a five-year period. This unprecedented ability to observe and measure the properties of so many objects will allow astronomers to create a much more detailed map of the universe.

What will DESI study?

DESI will study the properties of dark energy by measuring the distribution of galaxies and quasars in the universe. By measuring the distances and velocities of millions of galaxies and quasars, DESI will create a 3D map of the universe that will show how dark energy has affected the expansion of the universe over time. This map will provide astronomers with a wealth of information about the large-scale structure of the universe, including the locations of clusters and voids, and how they have evolved over time. This information will help astronomers better understand the role of dark energy in shaping the universe and its evolution over time.

One of the key goals of DESI is to measure the rate of expansion of the universe with unprecedented accuracy. This will be done by measuring the distances and velocities of galaxies and quasars at different points in time, allowing astronomers to trace the history of the expansion of the universe. By comparing these measurements to theoretical predictions, astronomers will be able to test different models of dark energy and determine which best fits the observational data.

In addition to measuring the expansion of the universe, DESI will also study the growth of large-scale structure in the universe. This will be done by measuring the clustering of galaxies and quasars, which will provide information about the distribution of matter in the universe. By combining this information with measurements of the cosmic microwave background radiation, astronomers will be able to test different models of the growth of structure in the universe and determine which best fits the observational data.

Another important goal of DESI is to study the properties of individual galaxies and quasars. This will be done by measuring the spectra of these objects, which will provide information about their composition, temperature, and motion. By studying the properties of these objects, astronomers will be able to better understand the processes that drive the formation and evolution of galaxies and quasars.

Why is DESI important?

DESI is important for several reasons. First and foremost, it is a powerful new instrument that will help astronomers better understand the nature of dark energy, one of the most mysterious and fundamental forces in the universe. By studying the distribution of galaxies and quasars, DESI will provide valuable insights into the properties of dark energy and how it has affected the expansion of the universe over time.

In addition to its scientific importance, DESI is also an important example of collaboration between multiple institutions. The project involves researchers from the Department of Energy's Lawrence Berkeley National Laboratory, the University of California, Berkeley, and the University of Arizona, among others. This collaborative effort has enabled the development of a cutting-edge instrument that will help answer some of the most fundamental questions about the universe.

Furthermore, DESI's unprecedented ability to observe and measure the properties of millions of galaxies and quasars will allow astronomers to create a detailed 3D map of the universe that will provide valuable insights into the large-scale structure of the universe. By studying the distribution of galaxies and quasars, DESI will help astronomers determine how dark energy has affected the expansion of the universe over time. This map will provide astronomers with a wealth of information about the locations of clusters and voids in the universe and how they have evolved over time.