People are typical as goldfish.
I mean in heavenly sense. Just as a goldfish cannot see its bowl from the outside, our position in the universe means that we cannot see our home galaxy, the Milky Way, as the rest of the universe sees it.
Thankfully, scientists have built the most accurate map of the Milky Way than, using a collection of large, bright stars. They have found that the Milky Way is not exactly as the artist's impression can make you believe ̵
It is the first time a map was built with the help of young stars – and the first measurement of how distorted our home galaxy is.
The paper, published in Nature Astronomy on February 4, describes information from Australian and Chinese astronomers to investigate the classic "Cepheids" – a collection of large, young stars in the Milky Way that can be up to 100,000 times brighter than the sun. Looking at Cepheid over time, you can see the stars pulse, sometimes dip or increase in brightness. By studying the length of these pulses, the distance between us and Cepheids can be found, which helps to build a map of the Milky Way.
The team drew the 1,339 Cepheids on a 3D map and built up the most accurate representation of how the Milky Way is formed. We know that the Milky Way is a spiral galaxy – a thin disk with a hundred billion stars circling around a huge supermassive black hole in the center of the galaxy. The gravity of all these objects holds the galaxy together.
But as you go further out, gravity fades and the gas that makes up the disk does not fall neatly into the thin plane as the stars approach the middle. 19659005] The research group, with the help of Cepheid's, showed how the Milky Way is not a flat cosmic disc-shaped like a lip-free frisbee or a pancake, but instead it is marked strongly in an S-like shape. So, with the pancake analog, the Milky Way path looks like a pancake, if you have just lifted it out of the pan before letting it unpleasant hide on the spatula.
And the twisted form is not necessarily unexpected – – Other spiral galaxies in the universe exhibit similar properties.
"Many large spiral galaxies actually show woven (S-shaped) disks in the gas distribution in their disks," says Richard de Grijs, co-author of the study and astronomer at Macquarie University.
"The disc" twists "because of the gravitational force on the rotating inner plate, dragging along the outer plate," de Grijs explained.
Exactly this form came to require a little more work.
"We would need (numerical) simulations of a realistic galaxy embedded in a dark materiahalo to see if we can reproduce the observations and find out how this happened," says Grijs. For example, observations from spacecraft such as the European Space Agency's Gaia, there is always room to improve the model even more.
"It would also be good to confirm the shape using larger samples of objects. "
NASA turns 60: the space agency has taken mankind longer than anyone else, and it has plans to move on.
Take it to Extremes: Mix crazy situations – eruptions of volcanoes, nuclear meltdowns, 30-foot waves – with daily tech, here is what happens.