Hi.
It's Barb, Meeple, PhD, with a Cosmic Game
Connection.
NASA recently announced that its TESS satellite
had observed its first star shredded by a
black hole in an event called a tidal disruption
event, or TDE for short.
Now this isn't the first time a TDE has been
observed, but what's unique about this one,
which is called ASASSN-19bt, is that it happened
to be in a region of the sky that TESS was
observing for a long time before the event
even started.
Now, what is a tidal disruption event?
It happens when a star wanders too close to
a black hole.
Rule number one of black holes is: Keep a
safe distance.
From far away, black holes look like anything
else in the universe that have mass, but as
you start to get close, weird things can start
to happen like the appearance of light bending
around the black hole to show you things from
the far side.
And if you get even closer, well things go
from weird to bad.
For the star, it wandered so close to the
black hole that it succumbed to the tidal
forces.
What that means is that the gravity on one
side of the star, the star closest to the
black hole, was so much stronger than the
gravity on the other side that it started
to stretch out, and the black hole pulled
in some of the matter while causing some of
the rest to be ejected out way from the system.
Now, the challenge of studying these types
of events is that we never know when they're
going to happen, and that can make it really
hard to turn telescopes to get the very earliest
moments of a TDE.
In this case, the ASAS-SN telescopes took
note first.
This is a network of telescopes that surveys
the entire sky every night looking for transient
events, things that suddenly brighten up.
It just so happens that ASASSN-19bt also is
in the TESS continuous viewing zone, a region
of the sky where TESS had its camera pointed
for nearly a year, meaning that we got data
from it before the event even started.
These early time observations are going to
allow astronomers to start solving some open
questions about TDEs.
For example, they've been seeing far more
ultraviolet radiation than they would expect
based on the amount of X-rays that they see.
It could be that the X-rays get bounced around
inside the debris of the star, taking away
their energy so they come out as ultraviolet
radiation.
It could also be that the disc of material
that forms happens further away from the star
than we would expect.
In any case, more observations will help astronomers
solve this puzzle and understand what happens
when a star is shredded by a black hole.
When I thought about that star wandering too
close to the black hole without an exit strategy,
the game that came to mind was Clank!.
Clank! is a deck-building treasure-hunting
race through a dungeon with an angry dragon.
The game is set up with the board in the middle
of the table and Artifacts and Secrets placed
out as indicated on the board.
The main deck of cards is shuffled and a Dungeon
Row of six cards is placed out for purchase
alongside some always available cards.
The dragon cubes are placed in the Clank!
Area, and the Dragon Bag placed nearby.
Players each get a player pawn, a supply of
Clank! cubes, and a starter deck of cards,
which they shuffle and grab a hand of five.
On their turn, players must play all cards
in their hand to move their pawn around the
board, to battle monsters, and to buy more
cards.
At the end of their turn they discard all
their cards and grab another hand of five.
If they ever need additional cards and they
don't have them, they shuffle their discard
pile and form a new deck.
The goal is to move your pawn through the
dungeon, grab an Artifact and some other treasure
along the way, and then get your noisy self
out of the dungeon before getting killed by
the dragon.
Things go bad when the dragon attacks.
It attacks when its symbol shows up in the
Dungeon Row.
During an attack, all of the cubes played
in the Clank!
Area are placed in the Dragon Bag and a number
of cubes pulled out based on the dragon's
rage number and any additional danger on the
board.
Player cubes pulled out in this manner are
placed on their health track at the bottom
of the board.
If that health track is ever filled up, that
player is knocked out.
If this happens in the depths or without an
Artifact, that player is left to the mercy
of the dragon.
The first to make it out, or the first to
get knocked out, sets a clock for all other
players to get out of the dungeon, because
that player's turn now consists of just triggering
dragon attacks with increasing danger each
time.
The game ends when all players have exited
the dungeon, all players have been knocked
out, or about the fifth round after the first
person exits the dungeon.
At that point, anyone who made it out or anyone
who was knocked out above ground with an Artifact,
counts up their points; and the player with
the most points wins.
During the game, you have a few choices to
make.
How do you craft your deck?
Are you going to put in a lot of movement,
or maybe a lot of Swords?
And how far into the dungeon do you want to
go?
The cheaper Artifacts are at the top.
Or do you go for the best Artifacts, which
are more toward the bottom?
But they're surrounded by monsters and locks
and dead-ends.
The thing that made me think about this star-shredding
black hole is that the deeper you go into
the dungeon, the more important it is for
you to have an escape plan.
The closer and closer an object gets to a
black hole, the faster and faster it has to
be able to travel in order to escape, until
it reaches a point of no return.
Similarly, the further into the dungeon you
choose to go in Clank!, the more important
it is to plan ahead and make sure that you
have the movement and Swords and everything
you need to make that mad dash in and out.
So the next time you get Clank! to the table,
try not to model your game after that ill-fated
star.
Thanks for joining me.
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You can follow me on Twitter and Instagram
as @MeeplePhD, and you can get additional
reviews and science on meeplephd.com.
This early data allowed astronomers...
Totally forgot what comes next.
Clank! is a...
