Cosmic Explorer (gravitational wave observatory)

Cosmic Explorer (CE) is a proposed next-generation ground-based gravitational wave observatory. It will consist of two L-shaped interferometers, similar to the LIGO detectors, but with significantly increased arm length (40 km and 20 km) that aims to increase the sensitivity of CE by more than an order of magnitude with respect to the 4-km long LIGO. It is planned to complement its proposed European counterpart, Einstein Telescope (ET), with a similar timeline.

In 2019, the CE consortium published a white paper paper laying out the necessary R&D. A horizon study was released in 2021 outlining the key science objectives, possible network configurations, and timeline. In 2024, a subcommittee of the National Science Foundation recommended for CE to be adopted by the NSF. The network is planned to be operational by the mid-2030s to 2040s.