Valerie had looked through Naomi’s microscope at the cyanophage like she’d known nothing about viruses, fully knowing what she’d helped create and was about to unleash.

She clicked open the files. The first was the formula for the virus. And then the formula for the vaccine. The notes from Bryony’s experiments, photos of magnifications of the virus under a microscope. Detailed write-ups of the virus’s morphology. Medication types and doses or other methods for treating existing cases. Everything they needed.

She sent it to Evan first. There were no notes, but her last message was marked as read. That was something, at least.

Immediately after, she fired the information off to the location of the missives the U.S. government had sent Valerie from Earth. She slid the data pod and the tablet into her pocket and climbed back down to the bridge to Hart and Hixon.

“Did she have it?” Hart asked. Lebedeva arrived, her expression questioning.

Naomi nodded, showing her the formula on the shared drives. Hart scanned it, eyes narrowed, and visibly relaxed. “Thank God.” Lebedeva let out her breath in a long, slow whistle.

“I’ve sent it to Evan and the return location of the U.S. missives. There has to be a way to relay it to everyone, though, right?” She didn’t trust the government not to weaponise or capitalise on it.

“I can do that,” Hixon said. She loaded the information and sent it as widely and broadly as she could in Earth’s direction. A satellite at Mars or near Earth should pick it up. If there were enough systems still online for them to receive it. Naomi tried not to think of Evan’s face. Of everyone she’d worked with back on Earth. Her friends, her schoolmates. The barista with a tattoo of dragon scales on her forearm who had taken Naomi’s coffee order every morning as she walked in to work. Naomi didn’t know her name, or anything about her, but she hoped she was all right. Naomi let out a breath. They’d done all they could.

“All right,” Hixon said. “Before next steps, I need to ask you something. All of you.”

They stared at her wordlessly.

Hixon’s face twisted towards the window, leaving her half in shadow. Mars was visible from their angle, a disk of rust. The tips of her right fingers were inked solid blue. “We have a choice. We can turn the ship around, loop Mars, and arrive at Earth in roughly another one hundred and thirty days. Or—” she paused—“we can continue on to Cavendish.”

“We don’t know if what we sent them is a viable cure,” Hart said. She checked the records again. “No confirmation yet.”

“We need to make a decision soon. As in, pretty much now,” Hixon said. “So it’s a leap of faith. We could end up pointing our way towards a nearly empty Earth.”