Lifeless Planets Society is a podcast that takes outlandish concepts about tinker with the cosmos – from snapping the moon in half to inflicting a gravitational wave apocalypse – and topics them to the legal guidelines of physics to see how they fare. Pay attention on Apple, Spotify or on our podcast page.
For probably the most half, galaxies solely are available two shapes: spirals and blobs. Whereas spirals might be majestic considered from the appropriate angles, the shortage of selection can get boring over the cosmic eons. So on this episode of Lifeless Planets Society, it’s time to spice issues up, galactically.
Our hosts Leah Crane and Chelsea Whyte are joined by Vivian U on the College of California, Irvine, an astronomer who research how galaxies evolve once they smash collectively and warp each other. In the actual world, galactic collisions can create unusual swirls and many-armed behemoths, however over time the chaos from the smash-up leads to simply one other blob. To make an enduring change, we’ll want instruments with a bit extra precision.
That’s the place the supermassive black holes are available. They could be capable of carve gaps by the mud and gasoline of a galaxy, creating extra detailed photographs. However gravity tends to complicate issues, and ultimately even these black holes would devour an excessive amount of matter and merge collectively, leading to yet one more blob. Maybe darkish matter could possibly be used as an alternative to create an invisible scaffold that shapes the distribution of the common matter that we are able to see.
Constructing such a strange-shaped galaxy – particularly one not like something {that a} pure galactic collision would create, corresponding to a galaxy with sharp corners or one in a recognisable picture like a giraffe – could be a approach to sign to aliens or future astronomers that we’re right here and we’ve got unbelievable cosmic powers.
The truth is, maybe this has already been achieved to the Milky Method by some unusual alien power – in spite of everything, we are able to’t see our residence galaxy from outdoors of it. We solely know its form by counting the celebrities that we are able to see in every route and constructing theoretical fashions, so we are able to rule out that our galaxy is within the form of a giraffe or one thing else wildly out of the abnormal. But when it have been, say, a sq. as an alternative of a spiral, it could be tough for astronomers to inform the distinction.
Subjects:
