Crypto exchange Gemini Space Station, founded by the Winklevoss twins, will debut Friday with Nasdaq investing $50 million via private placement, Reuters reported. The tie-up gives Nasdaq clients access to Gemini's custody & staking, while Gemini clients get Nasdaq's Calypso platform. Gemini, holding $21 billion in assets, aims to raise $317 million by selling 16.67 million shares at $17-19 each.