Download Citizen Sky Epsilon Aurigae Script for Fulldome Planetariums

Epsilon Aurigae
Eclipse Version for Fulldome Planetariums
Written by Ryan Wyatt • Narrated by Timothy Ferris
The stars appear changeless.
On a clear, dark night, we see the same constellations our ancestors saw long ago:
the Great Bear relentlessly pacing around the North Star, queen Cassiopeia
spinning topsy-turvy on her celestial throne.
But as our ancestors noticed, some stars change slightly over time. They don’t stray
noticeably from their constellation patterns, but a few change in brightness.
One such star, Algol, appears in the winter constellation of Perseus, the ancient
Greek warrior who beheaded Medusa, the serpent-haired Gorgon who threatened
Cassiopeia’s kingdom. Algol marks the “evil eye” of Medusa’s severed head… Every
three days, the star dims noticeably, as if the evil eye were winking at us.
If we could see what’s actually happening, Algol would reveal itself as two stars
orbiting each other. The slightly dimmer of the two stars passes directly between us
and the brighter star. When it does, we see Algol drop in brightness.
Algol lies too far away to be seen as two separate stars, except with our most
powerful telescopes. Instead, astronomers piece together this story by studying the
star’s “light curve.”
If you can imagine graphing the brightness of the two stars combined, as it changes
over time, Algol’s graph would look like this…
But of course, we only know the brightness of the star when we measure it. For
Algol, this means making repeated observations over three nights—and capturing
the system when the two stars are lined up and at their dimmest—in order to see
what’s happening.
Astronomers understand these types of stars well enough to have a pretty clear idea
of what’s going on with Algol. And many other stars fit a similar pattern.
But some stars provide a challenge for astronomers to interpret…
Citizen Sky Epsilon Aurigae Script for Fulldome Planetariums
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Not far in the sky from Perseus, we have another character from Greek mythology:
Auriga, the Charioteer.
The fifth brightest star in the Charioteer is called Epsilon Aurigae. Every 27 years,
it drops in brightness and mysteriously dims for nearly two years.
Let’s replace our classical view of the constellation with a connect-the-dots look.
The lines will help us as we leave our earthbound perspective and simulate a trip to
this fascinating destination. We can now see that the “dots” of the stars are actually
connected in three dimensions… Epsilon Aurigae lies some 2,000 light years from
Earth, much farther than the other bright stars in the constellation.
As we approach the star system, we see it as astronomers think it might look—a
bright star and a disk of dusty debris orbiting each other. We can imagine flying
around the system to get a good look…
The star is enormous. More than a hundred times the diameter of our own Sun,
Epsilon Aurigae shines 10,000 times more brightly.
Some observations suggest that the giant star may have a faint ring of material
around it…
Or it may not.
And the disk provides many puzzles! Astronomers can estimate the size of the disk
based on previous observations, and they now know that it contains gravelly
material—not the fine, tiny grains of dust that makes up most disks around other
stars.
Now astronomers are searching for the answers to tougher questions… How did the
disk form? How long will it stick around? And how does it remain intact?
Our own solar system may have formed from a disk similar to this. What can
Epsilon Aurigae teach us about our own origins?
To answer our questions, we need more observations.
From a distance, we cannot see the details of the Epsilon Aurigae system. Instead,
it reveals itself as only a single point of light in the starry night sky.
By making repeated observations of the star while it undergoes an eclipse, we can
measure its brightness and other attributes, tracking these carefully over time. The
process will take nearly two years!
The opportunity still exists for everyone to take part. The Citizen Sky Project
invites amateur astronomers from around the globe to contribute their observations
to the steadily growing collection of data that will help us piece together the story of
Citizen Sky Epsilon Aurigae Script for Fulldome Planetariums
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Epsilon Aurigae. Volunteers of all sorts can play a part—you do not need a telescope
or even access to dark skies. Help astronomers unlock the secrets of the night sky.
The stars may appear changeless… But we know better. And we want to know
more.
Citizen Sky Epsilon Aurigae Script for Fulldome Planetariums
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