Rocket Lab USA, Inc. (RKLB) experienced a significant 24-hour plunge of 5.94% during Thursday's trading sessions.

The sharp decline followed news that Congress declined to fund a planned 2031 Mars sample-return mission tied to NASA's Perseverance rover. This decision effectively ends Rocket Lab's opportunity to secure a multibillion-dollar contract, estimated at roughly $4 billion, for transporting Martian samples back to Earth, representing a major setback for the company's long-term growth narrative in high-margin deep-space missions.

Additional pressure stemmed from renewed speculation about a potential SpaceX initial public offering, with estimates suggesting a valuation that could exceed $1.5 trillion. This has prompted investors to reshuffle portfolios within the space sector, with many locking in profits from the previous year's rally and holding cash in anticipation of a future SpaceX listing, contributing to downward pressure on Rocket Lab and other space-related stocks.