Philip Plait's Blog, page 11

How did supermassive black holes get so big so fast? To find out, scientists turn to the dark sector

Astronomers have been facing a big problem in cosmology — the study of the formation and behavior of the Universe itself — for a while now. Literally the biggest: Where do the most supermassive black holes come from? 

Another big JWST milestone: The first deep, clear image, with galaxies galore

The James Webb Space Telescope has reached a new milestone: “Fine-phasing” calibration is now complete, which means all 18 hexagonal submirrors are acting as a single unit, and are now focused and aimed perfectly at a single spot in one of JWST’s many scientific cameras. This is a critical step in a long path to having the giant telescope ready for scientific observations, which will start this summer.

A nearby galaxy is giving birth to a brand new baby galaxy!

It's not often you get to see a galaxy being born. Especially one in our cosmic back yard, and especially especially one that's forming from gas ripped out of another galaxy. Especially-cubed from a galaxy that's incredibly well studied, so this wee baby galaxy was hiding in plain sight all along.

And if I may add one more especially, the discovery was made by a telescope that's not really a telescope in the way you think of them.

Explaining off-kilter black hole mergers may need a lot more black holes. A lot.

In 2019, ripples in the fabric of spacetime swept over Earth, the gravitational wave announcement of two black holes merging. But unlike the dozens of such mergers seen previously, this one was pretty weird. For one thing, the two component black holes were really massive — many dozens of times the mass of the Sun — but the signal received indicated other odd characteristics.

UPDATE: So, about that 'young' asteroid impact crater in Greenland... it's actually old. Really old.

Some time in the past, an asteroid a kilometer across slammed down into Greenland at a speed at least a dozen times faster than a rifle bullet. Releasing as much energy as 15,000 times the largest nuclear weapon ever exploded on Earth, it carved out a gigantic crater now called Hiawatha Crater, and it's over 30 kilometers across.

This much is known. The big question is, when did this happen?

The weird gets weirder: A fast radio burst traced to a nearby galaxy's globular cluster

One lesson astronomy teaches you is to never sit back and think, "Yeah, we totally understand this."

A tug on binary stars reveals the mass of the Tatooine-like planet Kepler-16b

It’s not Tatooine, but it’s kinda close. More like an Ohann or Adriana.

Those are fictional gas giants orbiting the binary suns Tatoo I and II in Star Wars, the stars made famous by Luke Skywalker wistfully watching them set as the desert wind blew through his 1970s hair. 

DKIST, our biggest eye on the Sun, is ready to bring the science

The Daniel K. Inouye Solar Telescope is now open for business. And by "business" I mean SCIENCE.

JWST update: All 18 eyes of the telescope now see a single, focused image! Kinda!

After a series of important steps for the James Webb Space Telescope that have gone really well, there’s even more great JWST news: The 18 small mirrors have gone through their initial alignment and focus, and can now produce a single image of a star!

The Dead Red Planet Part 2: Why did the waters of ancient Mars disappear?

As I wrote in yesterday’s article, there is copious evidence that ancient Mars had a lot of water on it, including, perhaps, oceans, even if there are arguments about where those oceans might have been.

But ancient oceans or not, we know they’re gone now. What happened to them? Or a better question is, what physical events caused Mars to lose nearly all its water?