Large Magellanic Cloud

The quest to push the hierarchical model down to that next level to find a satellite orbiting a satellite, that has been the absolute holy grail for validating LCDM on small scales.

Which brings us to the current record holder for this specific phenomenon, the Large Magellanic Cloud, or the LMC.

A beautiful galaxy.

It is.

Yes, they were satellites of the LMC that got dragged into the Milky Way's halo along with it.

So let me ask you this.

If we have already found satellites of satellites with the Large Magellanic Cloud, why is the discovery of Fornax 7 treated as such a critical, groundbreaking thing? W-why is pushing this search to the Fornax galaxy treated as a totally different regime of physics?

Because comparing the Large Magellanic Cloud to Fornax is like comparing a massive ocean liner to a wooden rowboat.

... just looking a little bit closer 'cause, uh, there's some pretty cool stuff in it.

Yeah, it's, it's actually quite easy to find if you are out in kind of a dark sky area away from light pollution because the constellation of Dorado is home to the Large Magellanic Cloud.

Ooh.

Yeah.

Hmm.

Uh.

And, um, you said it's the Large Magellanic Cloud.

Yeah.

The Montreal Protocol was signed on September 16th, creating an international agreement to phase out chemicals responsible for damaging the ozone layer.

Supernova SN 1987A was discovered in February in the Large Magellanic Cloud, becoming the brightest supernova visible from Earth in centuries.

Hmm.

Very exciting.

If this is the case, then they would be the Milky Way's first known binary globular cluster pair.

We found binary clusters in other galaxies, like in Centaurus A and the Large Magellanic Cloud, but scientists think it might be when these gravitationally bound clusters collide that we get the most massive globular clusters, like Omega Centauri.

So studying a binary cluster right in our own galaxy could produce some amazing insights into this process.

It's all speculation at the moment, but it's definitely cool to think about.

A case in point is the Magellanic Clouds, the largest satellite galaxies of the Milky Way.

The Large Magellanic Cloud is about 165,000 light years away.

It's about a third as wide as the Milky Way, and perhaps one-tenth as massive.

The small cloud is a little smaller and farther away.

But the observations revealed that most of the stars are moving outward, away from the center of the galaxy.

And that applied even to the stars in the center itself.

The most likely cause is the pull of the Large Magellanic Cloud.

Its gravity is dragging the stars away from their galactic home.

The warp violates simple disk geometry.

Sagittarius and the Large Magellanic Cloud also drive non-circular motion.

They're like outer gravitating masses.

These tracers become sparse at great distances, and you have to question whether or not the stars are at actual equilibrium.

And as I said, the Milky Way is not some isolated, perfect galaxy that's relaxed in a laboratory just hanging out.

The Sagittarius dwarf galaxy nearby, but not part of our galaxy, has reportedly crossed and perturbed our Milky Way's disk.

The Large Magellanic Cloud is massive, it's nearby, and it's dynamical.

It's rotating.

MOND also faces a challenge here, because it generally predicts an asymptotically flat curve for isolated galaxies.

However, supporters argue MOND's non-linearity allows external gravitational fields to matter, including influences from the Large Magellanic Cloud or the Sagittarius dwarf galaxy.

So we're

left with three main possibilities.

And the southern thread is foundational.

The whole field starts with SGR 0526-66 in the Large Magellanic Cloud in 1979, and the modern end runs through the Murchison Widefield Array in Western Australia.

Now, I believe you also have a story that we ran out of time to run during the week.

Indeed, the one we didn't run during the week, and it's a proper story.