Space

This portrait from the NASA/ESA Hubble Space Telescope puts the nearby galaxy NGC 4449 in the spotlight. The galaxy is situated just 12.5 million light-years away in the constellation Canes Venatici (the Hunting Dogs). It is a member of the M94 galaxy group, which is near the Local Group of galaxies that the Milky Way is part of.

NGC 4449 is a dwarf galaxy, which means that it is far smaller and contains fewer stars than the Milky Way. But don’t let its small size fool you — NGC 4449 packs a punch when it comes to making stars! This galaxy is currently forming new stars at a much faster rate than expected for its size, which makes it a starburst galaxy. Most starburst galaxies churn out stars mainly in their centers, but NGC 4449 is alight with brilliant young stars throughout. Researchers believe that this global burst of star formation came about because of NGC 4449’s interactions with its galactic neighbors. Because NGC 4449 is so close, it provides an excellent opportunity for Hubble to study how interactions between galaxies can influence the formation of new stars.

Source.

• One telescope, one purpose: The Hubble and James Webb space telescopes focus on detailed observations of individual objects, while the Euclid space telescope and the Vera C. Rubin Observatory in Chile capture large sections of the sky in the shortest possible time. The latter are therefore considered survey telescopes.
• Highly complex observatories: Modern telescopes are highly complex and benefit from sensitive camera systems in combination with sophisticated optics and telescopes. The Max Planck Society has been involved in the development of many observatories, some of which took decades to complete.
• The universe in three dimensions: A two-dimensional image from a telescope often contains different astronomical objects, such as galaxies, which are at different distances from Earth. This allows computer models of the three-dimensional universe to be compared with real observational data.
• The explosive universe: Speed is of the essence at the Vera C. Rubin Survey Telescope. By photographing the entire southern sky and all the objects it contains very frequently in succession, it also captures explosive and fast-moving events in the universe.

source https://chandra.si.edu/blog/node/719

cross-posted from: https://lemmy.world/post/31469771

Scientists find universe's missing matter while watching fast radio bursts shine through 'cosmic fog'

Half of the universe's ordinary matter was missing — until now.

Astronomers have used mysterious but powerful explosions of energy called fast radio bursts (FRBs) to detect the universe's missing "normal" matter for the first time.

This previously missing stuff isn't dark matter, the mysterious substance that accounts for around 85% of the material universe but remains invisible because it doesn't interact with light. Instead, it is ordinary matter made out of atoms (composed of baryons) that does interact with light but has until now just been too dark to see.

Matt from Standup Maths has an interesting project on the go. He has an opportunity to have some compute time on a lunar rover.

It's easy to think about the creation of the Universe like exploding fireworks: Start with a big bang, and then all the galaxies in the Universe fly out in all directions from some central point.

But that analogy isn't correct. Not only does it falsely imply that the expansion of the Universe started from a single spot, which it didn't, but it also suggests that the galaxies are the things that are moving, which isn't entirely accurate.

It's not so much the galaxies that are moving away from each other – it's the space between galaxies, the fabric of the Universe itself, that's ever-expanding as time goes on. In other words, it's not really the galaxies themselves that are moving through the Universe; it's more that the Universe itself is carrying them farther away as it expands.

A common analogy is to imagine sticking some dots on the surface of a balloon. As you blow air into the balloon, it expands. Because the dots are stuck on the surface of the balloon, they get farther apart.

Though they may appear to move, the dots actually stay exactly where you put them, and the distance between them gets bigger simply by virtue of the balloon's expansion. ... The thing we think of as the "center" of the balloon is a point somewhere in its interior, in the air-filled space beneath the surface.

But in this analogy, the Universe is more like the latex surface of the balloon. The balloon's air-filled interior has no counterpart in our Universe, so we can't use that part of the analogy – only the surface matters.

So asking, "Where's the center of the Universe?" is somewhat like asking, "Where's the center of the balloon's surface?" There simply isn't one. You could travel along the surface of the balloon in any direction, for as long as you like, and you'd never once reach a place you could call its center because you'd never actually leave the surface.

In the same way, you could travel in any direction in the Universe and would never find its center because, much like the surface of the balloon, it simply doesn't have one.