Gaia Captures a Dazzling Image of 2.8 Million Stars in the Milky Way
Gaia’s Breathtaking Star Survey
The European Space Agency’s Gaia star surveyor has captured a series of stunning images of the Milky Way galaxy, revealing an estimated 2.8 million stars in a densely packed region near the galactic center.
A Clear View into the Galaxy’s Heart
This particular image, taken on February 7, 2017, depicts an area two degrees below the galactic center. Its relatively low amount of interstellar dust provides Gaia with an unobstructed view into the inner sanctum of our galaxy.
A Stellar Census
The image covers 0.6 square degrees of the sky, with an estimated density of 4.6 million stars per square degree. This suggests that there should be roughly 2.8 million points of light in the picture, although no one has yet counted them.
Gaia’s Mission: Mapping the Milky Way
Launched in 2013, Gaia is on a five-year mission to map 1 billion stars, or roughly 1 percent of the Milky Way. This ambitious project aims to create a detailed map of our galaxy and help astronomers understand its evolution.
Astro spectrometry: Studying Stellar Motions
Gaia studies the motions of individual stars using a technique called astro spectrometry. By cataloging and analyzing these movements, researchers hope to gain insights into the Milky Way’s history and predict its future.
Data Dump-Images: Capturing Stellar Crowds
While Gaia typically focuses on individual stars, it occasionally encounters regions of space so densely packed that it becomes difficult to measure the motion of each star. In these cases, Gaia sends down a data dump-image of the entire area. The recent mega-star image is an example of such a data dump-image.
Gaia’s Legacy: Reshaping Our Cosmic View
Despite its relatively short time in space, Gaia has already made significant contributions to our understanding of the universe. Its first catalog of 1 billion stars, released in 2016, provided a wealth of new data for astronomers. A second catalog is scheduled for release in 2018, with subsequent catalogs planned for 2020 and 2022 if Gaia’s mission is extended.
Unveiling Cosmic Secrets from Gaia’s Data
Research based on Gaia’s data is already revealing fascinating insights. For instance, scientists have discovered that a star called Gliese 710 will pass through the inner Oort Cloud, a shell of icy debris surrounding the solar system, in around 1.3 million years. This event could potentially trigger a bombardment of comets into our Solar System.
Stellar Traffic in Our Neighborhood
Gaia’s data also suggests that there is much more “stellar traffic” in our area of space than previously believed. On average, 87 stars come within 6.5 light-years of the sun every million years.
Gaia’s Promise: A Treasure Trove of Astronomical Data
Gaia is amassing an enormous amount of data, estimated to fill 1.5 million CD-ROMs over five years. This data will require extensive processing before it can be fully analyzed, but it holds the potential to unlock countless new discoveries about our galaxy and the universe beyond.