Newshot Euclid Telescope Releases First Large-Scale Observation Data: Covering Over 900 Million Galaxies
IT之家 November 12 news, the European Space Agency (ESA) has released the first large-scale observation data from the Euclid space telescope mission. The mission aims to map the large-scale structure of the universe, and the data released this time covers observation results of more than 900 million galaxies. Scientists hope to use this to further study two components of the universe that remain shrouded in mystery: dark matter and dark energy.
The data released on Thursday local time covers a sky area equivalent to about 9,500 times the apparent area of the Moon as seen from Earth. The ultimate goal of the Euclid telescope is to create the largest three-dimensional map of the universe ever made by 2031, covering more than one-third of the entire sky.
The data released this time comes from about 13 months of observations by the Euclid telescope, totaling 1.7 PB (petabytes), equivalent to 1.7 million GB.
瓦莱里娅 · 佩托里诺 (Valeria Pettorino), ESA's Euclid project scientist and an astrophysicist, said: "This is an important milestone for ESA's Euclid mission and for everyone involved."
According to IT之家, the Euclid telescope was launched from Florida, USA, in 2023 and is currently collecting data on the universe's expansion process and the evolution of cosmic structures over time, while also studying the nature of dark energy and dark matter, as well as the role gravity plays in the large-scale structure of the universe.
佩托里诺 said: "Euclid will not only capture two-dimensional images of galaxies in the sky, but also measure their distances, thereby obtaining a third dimension. This will help us understand the positions of galaxies in space and time, trace 10 billion years of cosmic history, and observe the universe in all directions beyond the plane of the Milky Way."
She further explained: "Galaxies cluster along filamentary structures, surrounded by vast empty regions, ultimately forming a network structure we call the 'cosmic web.' Euclid will reconstruct this cosmic web and reveal how it has evolved over time."
"This research is very important because the specific shape of the cosmic web, including how many galaxy clusters and voids it contains, and how fast these structures evolve, all depend on the properties of dark energy and dark matter."
The universe is mainly composed of ordinary matter, dark matter, and dark energy.
Ordinary matter includes stars, planets, gas, dust, and the various substances familiar to humans on Earth, accounting for about 5% of the universe's total composition. Dark matter cannot be directly observed, but scientists can infer its existence through the gravitational effects it produces on galactic scales; it is estimated to account for about 27% of the universe's total composition. Dark energy is believed to be the cause of the universe's accelerating expansion, estimated to account for about 68%.
Neither dark matter nor dark energy emits or absorbs light, so they cannot be directly seen through conventional observation methods.
Previously, the data released by the Euclid mission covered only a few days of observations. The data released this time covers more than a year of observation records, but currently accounts for only 14% of the total target sky area in the visible and near-infrared bands of the telescope's future six-year observation plan.
This batch of data will be further supplemented next year, when the research team will release the first research results on dark energy and dark matter.
Gravitational Lensing Effect
Light from distant galaxies may be bent and distorted on its way to Earth by foreground ordinary matter and dark matter. This phenomenon is called gravitational lensing. Simply put, the gravity of foreground galaxies changes the propagation path of light from background galaxies.
Gravitational lensing is an important tool for scientists studying the distribution of dark matter. The Euclid observation data released this time includes about 15,000 strong gravitational lensing candidates, more than the total number discovered by humanity over the past half century.
Natalie Lines, a PhD student in astrophysics at the University of Portsmouth in the UK and a member of the Euclid Science Collaboration, said: "Gravitational lensing is like nature's own weighing tool."
She explained: "The degree to which light bends can tell us how much matter a galaxy contains, including invisible components such as dark matter. By studying thousands of gravitational lenses, we can understand the distribution of dark matter within galaxies, and thereby figure out how galaxies formed and evolved over the long history of the universe."
Lines also specifically mentioned the imaging clarity that the Euclid telescope demonstrates in large-scale cosmic observations.
She said: "Ground-based telescopes can observe large areas of the night sky, but due to atmospheric effects, the images they capture are often not clear enough. The Hubble Space Telescope and the James Webb Space Telescope can capture very clear images, but their observation range is usually only a small patch of sky. Euclid can achieve both at the same time. This is crucial for discovering rare, small objects such as strong gravitational lenses."
Because light emitted by distant objects takes a long time to reach Earth, the farther we observe, the further back in cosmic history we are actually seeing.
Currently, the most distant objects observed by the Euclid telescope are quasars. These objects are the bright cores of galaxies powered by supermassive black holes, with extremely high brightness. Euclid has precisely located about 60 million quasars.
Lines said: "Euclid has already discovered some very ancient quasars, which formed when the universe was only 5% of its current age. This means that the light we receive today set out from these objects about 13 billion years ago."