The galaxy subsequent door to the Milky Manner, Andromeda, has by no means appeared as beautiful because it does in a brand new picture from NASA’s Chandra X-ray house telescope.
The picture of the galaxy, also called Messier 31 (M31), was created with help from a variety of different house telescopes and ground-based devices together with the European Space Agency (ESA) XMM-Newton mission, NASA’s retired house telescopes GALEX and the Spitzer Space Telescope in addition to the Infrared Astronomy Satellite tv for pc, COBE, Planck, and Herschel, along with radio knowledge from the Westerbork Synthesis Radio Telescope.
All these devices noticed Andromeda in numerous wavelengths of sunshine throughout the electromagnetic spectrum, with astronomers bringing this knowledge collectively to create a surprising and complicated picture. The picture is a becoming tribute to astronomer Vera C. Rubin, who was chargeable for the invention of dark matter due to her observations of Andromeda.
Because the closest massive galaxy to the Milky Manner, at simply round 2.5 million light-years away, Andromeda has been very important in permitting astronomers to review elements of galaxies that are not accessible from our personal galaxy. For instance, from inside the Milky Way, we will not see our galaxy’s spiral arms, however we can see the spiral arms of Andromeda.
Each wavelength of light that was introduced collectively to create this unbelievable new picture of Andromeda tells astronomers one thing completely different and distinctive in regards to the galaxy subsequent door.
For instance, the X-ray knowledge supplied by Chandra has revealed the high-energy radiation launched from round Andromeda’s central supermassive black hole, often called M31*.
M31* is significantly bigger than the supermassive black gap on the coronary heart of the Milky Manner, often called Sagittarius A* (Sgr A*). Whereas our residence supermassive black gap has a mass 4.3 million instances that of the solar, M31* dwarfs it with a mass 100 million instances that of the solar. M31* can also be notable for its occasional flares, considered one of which was noticed in X-rays again in 2013, whereas Sgr A* is a a lot “quieter” black gap.
What connects Andromeda and Rubin?
Andromeda was chosen as a tribute to Rubin as a result of this neighboring galaxy performed an important function within the astronomer’s discovery of a lacking aspect of the universe. A component that we now name darkish matter.
Within the Nineteen Sixties, Rubin and collaborators exactly measured the rotation of Andromeda. They discovered that the pace at which this galaxy’s spiral arms spun indicated that the galaxy was surrounded by an enormous halo of an unknown and invisible type of matter.
The mass of this matter supplied the gravitational affect that was stopping Andromeda from flying aside as a result of its rotational pace. The gravity of its seen matter would not have been adequate to carry this galaxy collectively.
Since then, astronomers have found that each one massive galaxies appear to be surrounded by comparable haloes of what’s now often called darkish matter. This has led to the invention that the matter which contains all of the issues we see round us — stars, planets, moons, our our bodies, subsequent door’s cat — accounts for simply 15% of the “stuff” within the cosmos, with darkish matter accounting for the opposite 85%. The discovering has additionally prompted the search for particles past the standard model of particle physics that might compose darkish matter.
Thus, there is not any doubt that Rubin’s work delivered a watershed second in astronomy, and probably the most essential breakthroughs in trendy science, essentially altering our idea of the universe.
June 2025 has been a superb month of recognition of Rubin’s immense affect on astronomy and her lasting legacy. Along with this tribute picture, the Vera C. Rubin Observatory released its first images of the cosmos because it gears as much as conduct a 10-year observing program of the southern sky known as the Legacy Survey of House and Time (LSST).
Moreover, in recognition of Rubin’s monumental contributions to our understanding of the universe, the US Mint lately released a quarter that includes Rubin as a part of its American Girls Quarters Program. She is the primary astronomer to be honored within the sequence.