[ad_1]
NASA has found a “break” in one of the Milky Way’s spiral arms that could shed new light on the galaxy’s past.
The discovery, which looks like “a shard sticking out of a plank of wood,” according to NASA, spans 3,000 light years in front of one of the galaxy’s arms and includes stars and a cluster of four nebulae.
It is the first major structure identified that is located so differently from the corresponding arms and is an important finding, given that researchers still do not know the complete structure of the galaxy itself, as Earth lies inside. .
NASA has discovered a ‘break’ in one of the Milky Way’s spiral arms
The find looks “like a shard sticking out of a plank of wood,” NASA said. The structure spans 3,000 light years and includes stars and four nebulae
“It’s like standing in the middle of Times Square and trying to draw a map of Manhattan Island,” NASA wrote in a statement.
Experts were able to find the feature using NASA’s Spitzer Space Telescope – before his retirement in January 2020 – along with data from the European Space Agency’s Gaia mission to measure the precise distance of stars in the arm .
According to ESA, the Gaia spacecraft, launched in 2013, is designed to create a three-dimensional map of the Milky Way with “unprecedented positional velocity and radial velocity measurements.”
After reviewing the data, the scientists were able to determine that the “broken” structure is moving at almost the same speed and in the same direction in space as the arm itself, known as the Sagittarius arm.
“A key property of spiral arms is the force with which they wrap around a galaxy,” lead author of the study, Caltech astrophysicist Michael Kuhn, said in the statement.
Experts were able to find the feature using NASA’s Spitzer Space Telescope (pictured) – ahead of its January 2020 retirement
“Most models of the Milky Way suggest that the Sagittarius arm forms a spiral that has a pitch angle of about 12 degrees, but the structure we looked at really stands out at an angle of almost 60 degrees.”
This is done by measuring the tilt angle of the arm and comparing it to a circle, which has a tilt angle of 0 degrees.
However, new observations suggest that the structure “really stands out at an angle of almost 60 degrees,” Kuhn added.
“When we put the Gaia and Spitzer data together and finally see this detailed three-dimensional map, we can see that there is a bit of complexity in this region that just wasn’t apparent before.”
The newly discovered structure also contains four nebulae – the Eagle Nebula (which contains the Pillars of Creation), the Omega Nebula, the Trifid Nebula, and the Lagoon Nebula.
A nebula is an interstellar cloud of gas, dust, and hydrogen in space.
It is the first major structure identified located so differently from the corresponding arms
It is still not clear why the structure and the arm have very different angles.
It is still not clear why the structure and the arm have very different angles.
Scientists don’t yet know how or why the arms of galaxies – in this case, the spiral arms – form, but the discovery could shed light on this.
“Ultimately, this reminds us that there are many uncertainties surrounding the large-scale structure of the Milky Way, and we need to look at the details if we are to understand this larger picture,” said one of the co-workers. – Study authors Robert Benjamin, in the press release.
“This structure is a small piece of the Milky Way, but it could tell us something important about the Galaxy as a whole.”
The study was published in July in the scientific journal Astronomy & Astrophysics.
[ad_2]
Source link