Scientists have used NASA's Hubble Space Telescope to gain new insights into the nature of dark matter, the invisible substance that makes up a significant portion of the universe's mass. Dark matter, which accounts for about 27% of the mass and energy in the universe, has long been a subject of study and debate in astrophysics. Previous observations have suggested that dark matter is evenly distributed throughout galaxies, contrary to computer simulations that predict a concentration of dark matter in a galaxy's center. To resolve this discrepancy, a team of astronomers led by Eduardo Vitral of the Space Telescope Science Institute (STScI) analyzed the positions and movements of stars in the Draco dwarf galaxy, located about 250,000 light-years from Earth. By combining line-of-sight velocity measurements with proper motion data, the team created a comprehensive three-dimensional model of stellar movements in the galaxy. The study, which spanned 18 years of Hubble observations, provides the most accurate understanding to date of the distribution of dark matter in a galaxy. The research not only advances our knowledge of dark matter but also highlights the value of long-term astronomical observations in revolutionizing our understanding of the universe's composition and structure [0ef6b83f].
In addition to the study on dark matter, NASA has released new maps that capture the outskirts of the universe. The maps were created using data from the Dark Energy Survey, a project that aims to understand the nature of dark energy. The maps show the distribution of galaxies and provide insights into the large-scale structure of the universe. The data was collected over a period of six years and covers an area of about one-eighth of the sky. These maps will help scientists study the expansion of the universe and the role of dark energy in it. The combination of the Hubble observations on dark matter and the new maps from NASA's Dark Energy Survey contributes to our understanding of the composition and structure of the universe, shedding light on two of its most mysterious components [180d52ef] [0ef6b83f].