Lost, Late or Not Yet Flown: Thirteen Spacecraft Outside the Usual Story

Mars 5 was a Soviet orbiter, catalogued as 3MS No.53S, launched on 25 July 1973. It entered orbit around Mars in 1974 but failed a few weeks later, so the orbit it reached was brief.

Mars 6 was launched on 5 August 1973 as a 3MP bus with a lander and a coast stage carrying instruments to study Mars during a flyby. All contact with it was lost, which makes it a companion to Mars 5 in the same Soviet program.

Suisei, first known as Planet-A, was a Japanese probe from the Institute of Space and Astronautical Science. Launched on 18 August 1985 as a flyby mission to Halley's Comet, it operated until 1991.

Phobos 2 was the last space probe designed by the Soviet Union, built to study the Martian moons Phobos and Deimos. It left Earth on 12 July 1988 beside its twin Phobos 1 and entered Mars orbit on 29 January 1989, but its signal was not reacquired after 27 March 1989.

Clementine was a joint project of the Ballistic Missile Defense Organization and NASA, launched on 25 January 1994. It tested sensors and spacecraft components in space and observed the Moon and the near-Earth asteroid 1620 Geographos, and the atlas records it as partly successful.

Fuji shows a path not taken. Japan's National Space Development Agency proposed this crewed capsule through its Advanced Mission Research Center in December 2001, and the design was ultimately not adopted.

Atlas V first flew on 21 August 2002 as the fifth major member of the Atlas family, developed by Lockheed Martin. United Launch Alliance has operated it since 2006 for missions such as New Horizons, Juno and Perseverance, and stopped selling new launches in 2021 in favor of Vulcan Centaur.

Electron is Rocket Lab's two-stage small-lift launcher. Its first flight was on 25 May 2017 from the Mahia Peninsula in New Zealand, with a first fully successful orbital launch in January 2018, and it was the first orbital-class rocket to use electric-pump-fed engines, nine Rutherford engines on its first stage.

Hakuto-R Mission 1 was a private Japanese lunar landing attempt by the company ispace, launched in December 2022. Communication with the lander was lost during the final seconds of its April 2023 descent, and the atlas records the mission as failed.

Sora-Q is a miniature lunar rover built by JAXA with Tomy, Sony and Doshisha University. It was deployed after landing on 19 January 2024 and operated successfully, a small craft with a completed mission.

HTV-X, the New Space Station Resupply Vehicle, is a Japanese cargo spacecraft built by JAXA as the successor to the H-II Transfer Vehicle. HTV-X1 launched successfully on 26 October 2025.

Starfall is a planned SpaceX capsule class meant to return cargo from orbit or near orbit for uncrewed point to point delivery. It builds on SpaceX experience with Dragon capsules and Starship reentry, and the atlas lists it as planned.

L4 is a proposed European Space Agency mission to Enceladus, made up of an orbiter and a lander. If approved it would launch in the early 2040s, and Enceladus has been the agency's top priority for future exploration since 2024 because of signs of possible habitability.