#sunlike star

[quasarlasar]

EMOTIONAL TIDAL DISRUPTION EVENT

Finally colored a new space comic after…2 years??

A YouTuber I originally respected put out a video saying that astrology is useful and good, actually. As an astronomer/astrophysicist, I felt obligated to leave a comment as to why it doesn't work. I ended up getting hundreds of angry comments from astrology fans that kept being added to for months.

One of the comments claimed that just like the Moon creates tides in the ocean, it creates "emotional tides" in people. This phrase sounded so silly that I had to save it for future reference. I then realized that, if "emotional tides" were a real phenomenon, then that would imply the existence of emotional tidal disruption events.

Hence this comic.

Tartarus is so large that even a giant star gets swallowed whole. His tides are therefore nowhere near strong enough to rip apart a normal-sized star like Stella.

I have sketched many comics where Stella vents or cries into Tartarus' event horizon, but this is the first time I've colored one. Tartarus can't exactly hug or cuddle Stella to comfort her, but he can act as a big empty void to scream into.

Stella's first line is of course, a reference to the infamous "You're tearing me apart Lisa!" from the so-bad-it's-good movie The Room.

[quasarlasar]

I’m getting closer to finishing the final draft of my sci-fi novel I have been bragging about for 10+ years. It is the story of how Stella and Tartarus first met, and how they altered the history of the quasar galaxy Antiocheka they live in.

I originally had much grander dreams for it, but I’m hoping to post it online somewhere next year.

Here is an excerpt of a scene in which Stella first talks to Tartarus. The supermassive black hole definitely has quite a different perspective from the stars. Though Stella, having been taught black holes are mindless monsters, is shocked to find that a black hole even has a perspective at all…

NOTE: some of what Tartarus says is highly speculative. We don’t know if supermassive black holes formed before their galaxies did or triggered the formation of the first stars. It is also now thought that the reionization of the Universe was primarily done by stars, not quasars.

In Tartarus’ case though, this was true. He was born a primordial black hole shortly after the Big Bang and preceded his galaxy. And while the Universe as a whole wasn’t reionized by quasars, in Tartarus’ galaxy cluster he did do a lot of it.

[quasarlasar]

I’m just kind of burnt out on digital art for now...so instead have this chalk pencil drawing of Stella encountering a traveling black hole.

It is a little-known effect, but if the magnetic field strengths in a black hole’s jets are asymmetric, the black hole will experience a net thrust. A large asymmetry in jet power is possible, and so in principle, one could get even a supermassive black hole moving.

The effect is discussed here: 

https://ui.adsabs.harvard.edu/abs/1992ApJ...390...46W/abstract

And also here:

https://ui.adsabs.harvard.edu/abs/2010ApJ...717L...6B/abstract

Fortunately for us, it does not appear this process is really common in nature. Which is probably a good thing.

[quasarlasar]

EVEN THE BLACK HOLES ARE GETTING SICK NOW

I cannot settle on a format for my comics, and I keep experimenting with new designs. Here, gravitational wave speech is depicted in speech bubbles that are empty and ripple-shaped. Electromagnetic wave speech is still depicted in regular speech bubbles.

This comic takes place several billion years after most of the comics with Stella and Tartarus (which take place ~3 billion years after the Big Bang). This has given Stella plenty of time to learn how to perceive and create gravitational waves to a great degree, and so she speaks to Tartarus in his native gravitational language instead of the light-based language of stars.

Now, a supermassive black hole normally has a temperature an insanely tiny fraction of a degree above absolute zero, so 10 Kelvins would actually be a very high temperature for Tartarus to run, even though to us that is barely any heat at all. 

As for what is causing Tartarus to feel sick? I’m not entirely sure, but probably some causality-violating eldritch abomination went down the wrong way, instead of being destroyed in the all-consuming hellfires/macerators/trash compactors that are black hole singularities. 

Don’t worry too much about Tartarus though...he’ll probably end up burping a couple of times and then somehow feel better.

===============

Some additional notes for curious people:

-The ‘wormhole endoscope’ Stella refers to is the process of dropping one mouth of the wormhole into Tartarus, while she looks through the other end of the wormhole that is still above his event horizon. If you could create a wormhole (already a big if) you could potentially use this to peer inside a black hole until the moment the mouth you dropped in hits a singularity. You do need to make sure the end you’re looking through is in free fall, though, otherwise the wormhole will collapse due to the relative time dilation between the two mouths. During the process, the black hole’s event horizon temporarily deforms quite drastically due to the unusual energy densities one would need to build a wormhole, which is why Tartarus is very reluctant to undergo the procedure.

(If you have a university internet/VPN you can find this here: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.48.1607)

-In the first panel, the galaxy of Antiocheka is depicted as a giant elliptical galaxy. This is because the host galaxies of quasars that existed in the early Universe are generally thought to eventually become what we see in the modern Universe as giant elliptical galaxies at the centers of galaxy clusters. In most of the comics I show with Tartarus and Stella, Antiocheka is younger and still has plenty of star formation. By the time 7 billion years have passed since the Big Bang, however, giant elliptical galaxies have stopped forming stars for the most part. Antiocheka will continue to grow by absorbing other galaxies in its cluster that fall into it, but there will not be any bright blue massive stars or colorful nebulae. 

-Tartarus has a low mass accretion rate here, as is standard for supermassive black holes at the centers of giant elliptical galaxies, so his accretion disk is optically thin enough to see hints of the galaxy’s stars through it.

[quasarlasar]

IMPORTANCE

Well, it’s been a long while hasn’t it? But finally, I’m back making new art.

A lot of things have happened, so I felt like doing something more introspective than usual this time. For whatever reason, I love drawing Tartarus and Stella having quiet conversations about philosophical things. Maybe it’s just the absurdity of the comparatively* tiny Stella juxtaposed against the great dark void of Tartarus and just...kind of talking to it.

Usually when I draw this sort of scenario Stella is far off to the side of Tartarus’ shadow and so he basically appears as a dark wall to the side of the page. I wanted here to more fully capture just how supermassive he is, so she is front of him this time, silhouetted against his darkness. One of these days I intend to do a sketch illustrating how his “face” is not a specific scale to the rest of his body, given that his eyes are just random gas clouds he uses to try to make facial expressions.

Stella’s backstory is hinted at towards the beginning of the comic, but I intend to save the details for the science fiction novel** I have been working on...or am at least trying to (LOL grad school).

Okay...now for some science notes...(I really need something like an ExplainXKCD wiki).

-It is commonly stated that you can see the infinite future of the Universe while falling into a black hole, but this is only true if you hover at the event horizon (which takes infinite energy), or get vaporized by all the light of the infinite future hitting you as a singularity while you’re already inside the black hole. Basically, it’s not a sight you can actually witness. However, given that Tartarus is the black hole itself, I imagine the part of him that is inside the event horizon has seen the infinite future, and so he knows what will happen to everyone (including Stella). He does not tell anyone though, as this future has already happened to part of him, and thus, if he tells anyone, he’s essentially communicating into the past. Stella would not be able to change the future with this knowledge (since the future events have in some sense already happened) so he figures it’s best he never shares it with anyone. The knowledge does inflict deep psychological scars on him, however, though he usually hides it pretty well...

-Stella essentially is not thinking very clearly here, and in her desire to get closer to Tartarus, decides to approach him in the direction opposite his rotation. This causes her to precipitously drop towards him, which is of course, not good. Tartarus’ reaction in the third-to-last panel where he’s frowning/grasping at her is kind of a confused mix of emotions: the instinctual part of him that’s like “hey look free food,” the more rational part of him that’s like “wait a minute is she really doing that?” and the emotional part of him that’s like “NOOOO I don’t want to hurt you please don’t fall into me please don’t”

-I have no idea what the view from inside a black hole’s ergosphere would look like. It’s not something that’s really been modeled, as far as I know, given that it’s a view we’ll likely never see. I just filled it with swirling, turbulent gas, the blue representing violet/UV light, the green representing gamma rays (like from positron-electron annihilation or pion decays†) and the magenta representing x-rays. 

As for why there’s also giant teeth? Well, Tartarus’ ergosphere is sorta the equivalent of his mouth, given he can scoop material up into it and suspend it above his throat/event horizon, locking onto it with his rotation, before swallowing it or spitting it out at relativistic speed. So Stella kind of visualizes his gravity as grasping fangs.

-The Penrose process would involve a) Stella falling towards Tartarus at relativistic speeds b) getting ripped in half c) half of her falling into Tartarus while the other half gets ejected at even more relativistic speeds. So her reluctance is obvious.

* I mean, Stella is a sunlike star, so she’s not actually tiny. 

**If you’re wondering why the celestial body characters’ descriptions on my webcomic character pages are short compared to say, the natural disaster characters’, this is why. Most of the details of their life story I’m saving for the science fiction novel.

†So it turns out that an optically thin accretion flow as seen across most of Tartarus here would not have many gamma rays from pair annihilation. So this could mostly be from the decay of pions produced by proton-proton collisions. Then again, I imagine the accretion flow to be much denser in Tartarus’ ergosphere, and the magnetization to be higher, allowing more positron-electron pairs to be created. Make of this what you will. #nitpicking

[quasarlasar]

Helium of Mourning

(Sung to the tune of “Hope of Morning” by Icon for Hire)

CNO cycle’s like an explosion all too fast

Blurs the all the time right past

A last hurrah, on ashes I’ve made

Nothing but myself to blame

I’m afraid of the helium flash inside

Nowhere to hide but in my envelope sublime

To the main sequence I’ll compare

And look on a lifetime beyond repair

I guess I’m fusing myself to death

With every nuclear reaction step

What if my life has been meaningless?

What if my core’s misleading us?

I try to capture every alpha particle as it comes to me

Bottle up carbon and oxygen and let it keep me company

[Chorus:]

When the helium of mourning starts to ignite in me

I won’t let darkness have its way with me

The helium of mourning lets me keep up the fight

I won’t give into gravity tonight...

When I’m a PNe or a white dwarf

Whichever happens first

I’ll need you to reassure me I shone my light’s worth

Or worse! What if my life’s reduced to just a metal yield

Nothing but a change in alpha/Fe for stars in the field

Whatever, there’s just too many nuclear reactions to track

I really can’t remember what’s the cross section for s-process impact

Now all the Pop I kids have crazy metals like Zr, Y, Sn

Elements with made up names, passed around the ISM

My demise cannot be cured by any nuclear process known

Dooming my planets that orbit relatively in close

Please don’t investigate my spectra, I don’t want anyone to know

The selfishness that takes my planets down 

When it’s my time to go

[Chorus]

Try as I might to keep it together

I can’t just keep on shining forever

Hide the darkness inside, until I’m just a burnt ember

Cooling off and fading forever

On and on I wonder what went wrong inside my core

I don’t have to have the answers (not that they’d help me anymore...)

But though I may die, the pain won’t fade away

So easily from 10 Gigayears of failure and shame...

[Chorus]

(Apologies to Icon for Hire)

[quasarlasar]

The Five Stages of Grief/Sunlike Star Post-Main Sequence Evolution

Denial/Subgiant

“Main sequence? What main sequence? I’m not evolving off the main sequence! Wow, I feel really tired for some reason...”

Anger/Red Giant Branch

“ALL YOU UNGRATEFUL LITTLE PLANETS! HOW’S THAT SUNRISE NOW?”

Bargaining/Horizontal Branch

“Oh, yeah! Helium fusion! That’ll buy me some time...right? RIGHT?”

Depression/Asymptotic Giant Branch

“The dust is what remains of my dreams.”

Acceptance/Planetary Nebula

“Releasing this form.”

[quasarlasar]

My March for Science sign.