The woman writes letters to her sister.

In her first letter, the woman says that she’s on Ulysses, on a purple sand beach, light years away from her sister. She says that Ulysses has three suns and is populated by both natives but also folks from Terra Two. It’s a planet which was intended to be a tourist destination, but the natives stayed resolute. Soon, the woman will go on a solo mission, as part of Terra Two’s Space Force, where they will map the stars. She hopes the trip will give her a sense of independence and initiative. In her letter, she encloses some chocolates from her planet.

In her second letter, the woman says she’s gotten the letters and packages from her sister. She congratulates her sister on her child and says she doesn’t have any advice for her sister’s city-planning job. The woman sends pictures of her bedroom, kitchen, and cabin on her ship, as she proceeds along her solo mission.

In her third letter, the woman asks her sister about their parents who left Terra Prime for Terra Two before Terra Prime collapsed. The woman barely remembers their time there, on the gray planet, which was slowly but surely being ravaged by natural disasters. Now, their parents are gone, and the sisters are all they have. Whenever the woman lands on a planet, she wonders about whether it’s like how Terra Prime was. She spends especially a lot of time on another planet where black and brown people, like them, are. She reflects on how, after their parents died, the sister took care of the woman, until she was old enough to join the Space Force.

In her fourth letter, the woman asks her sister if she’s really getting her letters, feeling the distance between them now. She asks about her nephew, and finds out that time is moving along strangely. In space, even as she maps the stars, she feels lost, especially as she heads into a new galaxy. All she can think about is her sister.

In her fifth letter, the woman remembers one winter where she and her sister were stuck in the snow, in their car. Even though the snow threatened to kill them in the cold, her sister kept composure and assured the woman that things would be okay. Eventually, they were saved by a rescue team, and her sister never let her go even then. The woman then reflects on her new galaxy and how it reminds her of the Milky Way.

In her sixth letter, the woman commends the success of interdimensional travel, warping time and space. The woman is now on Earth, which is Terra Prima. There, everything is still green and blue, peaceful. There, she meets the Earth versions of herself and her sister. Her Earth sister is emotional at the sight of her, and her Earth self gets along with her well. Time, too, is warped. The woman grows older much faster than her sister does. Now, all she can do is think about all the possible times they could have gone through together. Maybe, she says, they will see each other someday, after a while.