Someone help me out: maybe that’s really magnetic for a star, but 43,000 gauss isn’t insanely strong, is it? We measure some magnets in teslas, which is 10,000 gauss.
So it’s a 4.3 tesla star.
I’m guessing this is somehow proportionate to the mass of the magnet, so a 1 tesla, 1 gram magnet is going to be much less powerful than a 1 tesla, 1 kg magnet? So something the size of a star would still have a massive magnetic field?
Well you have to put it in perspective. The earth has a magnetic field of 0.3 - 0.5 gauss. That puts this star at 143,000x as strong. Then you compare to the sun, which is 1 gauss, so this star is 43,000x as strong.
Okay, you might say, that's a lot, but this star is also 4x as massive as the sun. What about other stars bigger than the sun?
Beltugese is 16.5 - 19x the mass of the sun, and it's magnetic field has been carefully studied and measured to be about 1 gauss.
So yes, for a main sequence star this beast is a huge outlier.
No, this not a repost. It is a brand new version (as of yesterday) of the older article by the same author posted a week ago. Spoiler alert: no new constants have been found.
This tells us something remarkable and unexpected to many: Earth, the largest rocky planet in our entire Solar System, is almost as “super” as a rocky planet can get. If you managed to form an Earth-sized planet early on in your Solar System’s history, it would only need to get a little bit larger and more massive before it became capable of hanging onto volatile molecules like ammonia, methane, and even hydrogen and helium. And once you become rich in volatiles, you’re guaranteed to no longer be rocky, but rather more like Neptune, with a large gas envelope around you.
This I find very interesting. How many definetly rocky Exoplanets have we discovered so far? Or at the Exoplanets we have found so far alla gas giants?
So we can deduce that the density and volume of the gas envelope is a function of the mass of the planet, the temperature of the star and the distance of the planet’s orbit. This would mean, generally, that rocky planets are most common closer to the star than gas giants, and so the configuration we see here is not uncommon. This would also mean an earth sized planet occupying an orbit a little farther out would be bigger with a larger gas envelope, and that in our orbit the planet would be bigger and have one.
That is an interesting observation. This means that dwarf stars, which are much more common than a star like the sun, are very unlikely to have a rocky planet with the same size and orbit of Earth. But a giant star like Betelgeuse might have a rocky planet much bigger than Earth. Although a full orbit of Betelgeuse would take a long time.
Here is a quick summary. Astronomers used to assume that planets as big as 2x Earth diameter could be rocky planets. But now we know that most planets bigger than 1.3 Earth diameter are mini Neptunes. Although sometimes rocky planets can get as big as 1.5 Earth diameter.
Neptune’s diameter is about 50 megameters. Earth’s diameter is 12.7 megameters. So per the article, most planets bigger than a 16.5 megameter diameter is probably a mini Neptune. Although a rocky planet could be as big as a 19 megameter diameter.
<span style="color:#323232;">The astronomers will tell you it is just an optical illusion, a pair of galaxies caught in the act of mating as seen from the wrong angle. Happens all the time.
</span><span style="color:#323232;">
</span><span style="color:#323232;">In the 1960 and 70s, Halton Arp, an astronomer at Hale Observatories in Southern California, caused a ruckus by asserting that galaxies millions of light-years apart according to conventional cosmological calculations — but which appeared superimposed together in the sky — were interacting locally. His claim cast doubt on the Big Bang theory of the universe. Astronomers now agree that he was wrong.
</span><span style="color:#323232;">
</span><span style="color:#323232;">Now a genuine question mark has been discovered, in the corner of a recent Webb telescope observation of a pair of dust clouds known as Herbig-Haro 46/47 that are in the process of forming into two stars. The discovery made a splash on social media. “Ze space mall information kiosk has been found by JWST,” a commenter joked on X, the site formerly known as Twitter.
</span><span style="color:#323232;">
</span><span style="color:#323232;">Chris Britt, an astronomer at the Baltimore-based Space Telescope Science Institute, which runs the Webb telescope, attempted to explain. “This particular pair is so far away, it’s hard to make out much detail,” he said in an email exchange. “But there are some similar looking galaxy mergers that have been seen closer to us, including this one called II Zwicky 96.”
</span><span style="color:#323232;">
</span><span style="color:#323232;">If you accept the spooky rules of quantum mechanics and the premise, as Einstein disapprovingly put it, that God plays dice with the universe, then you have to accept that chance and randomness are a fundamental bedrock of reality. In such a universe, where the laws of physics have been grinding away for 14 billion years, coincidences are unforeseeable but inevitable.
</span><span style="color:#323232;">
</span><span style="color:#323232;">Image
</span><span style="color:#323232;">A thin horizontal orange cloud known as Herbig-Haro 46/47 is uneven with rounded ends and tilted from bottom left to top right. At its center is a red-and-pink star with prominent, eight-pointed diffraction spikes. The background is filled with stars and galaxies.
</span><span style="color:#323232;">An image of Herbig-Haro 46/47. The question mark appears at the center-bottom of the frame, to the right of the reddish cloudy material.Credit...NASA, ESA, CSA, Joseph DePasquale (STScI), Anton M. Koekemoer (STScI)
</span><span style="color:#323232;">
</span><span style="color:#323232;">Still, there are times when it’s worth stepping back to listen to “the music,” as Einstein once referred to the beauty and mystery of the cosmos. You are free to consider that question mark as alien graffiti, a comment on both their and our relation to existence. Point being, we’ve barely begun to know anything — that’s why we build telescopes.
</span><span style="color:#323232;">
</span><span style="color:#323232;">Once the Webb has completed its rounds of investigations two decades from now, we might know a bit more about how this bowl of stars works. But we still won’t know why we’re here. That question mark, our profound cosmic ignorance, is one of the great gifts of science.
</span>
Not really. If more material falls in, its mass and size increases (the volume increases faster than the mass, which is why it’s so unexpectedly low density in the first place), but otherwise it just sort of sits there.
Over the very long term, it will evaporate away by Hawking radiation. But that’s a very very slow process. Like, long after everything else in the universe has ended.
That’s the thing about black holes that always blows my mind. I don’t understand how the larger a black hole is, the less dense that it is. In my mind, I always think of black holes as super dense objects containing so much matter in such a little space that the gravity is crazy strong. How can something so not dense be a black hole? It doesn’t make sense to me!
To be fair, the density is calculated from the event horizon, which is a somewhat arbitrary boundary. All the mass is still concentrated at the singularity which is still infinitely dense, just… a bit more so.
Ah, I didn’t realize that. I guess that’s a little more terrifying. Sounds like you could pass the event horizon and not be instantly crushed, but would have no way of ever escaping. You’d just eventually get sucked into the singularity.
astronomy
Newest
This magazine is from a federated server and may be incomplete. Browse more on the original instance.