Very few thaumaturgy students were accepted for training, and it wasn't flattering if you were. It usually meant the student had completed their third cycle of study and had shown no particular aptitude for the more traditional magic systems, or were about to fail out altogether.
Also, the student was required to be an organ donor, and agree to an advanced directive that if their Anima did not return within 7 days, the body would be euthanized and the components harvested for ingredients.
If the Anima was out on its own longer than 7 days, on the 8th day it would go supernova.
Literally. That's what many supernovae are. Not all of them, but a lot. As the Codex Dessicantem states, "It is bad when one thing becomes two."
There is furious debate among the scholars about how the Earth has so far been spared from these lightyears-wide explosions when as far as anyone knew, humans on Earth were the only ones who could astral project. Granted, Animas were not strictly bound by the limitations of physics, but the nearest supernova recorded was still several galaxies over, never close enough to threaten Earth. Luck, maybe. Still, best not to take any chances, so that euthanasia protocol was developed.
Too bad he wasn't going to make a sanctioned attempt. He was a promising chronomancer, and the school would not risk his potential.
He prepared the spell, and went out on his own. His Anima tore away from his corporeal form, and he was away.
He could not describe the feeling, nor what he saw. It was almost entirely unlike swimming through a vibrant coral reef surrounded by brightly-colored fish and looming, counter-shaded predators. But not entirely unlike that.
He searched and searched for her, for six days. He couldn't find her, and he couldn't find the way back to his own body. He despaired, and searched on.
At dawn, on the seventh day, he received a gift. Somehow, like the half-memory of a dream, he knew where she wasn't. Absolute, perfect, knowledge of where she could not be. And he strove to that place with all his might. At dawn, on the eighth day, he arrived, and his last thought was of her.
"A new supernova popped into visibility on May 19 in the Pinwheel Galaxy, (alternately designated as Messier 101, or M101)."
-Bartleby, et al., 2023 'Multidisciplinary Observation and Measurements of Transient Events -Journal of Astronomy and Astrology
THE END
Author's Note: Okay one more since it's the last day of Short Story Sham Writing Month. Goodnight!
