Sidus Space Inc-A美股招股说明书(2025-12-23版)

19,230,800 Shares of Class A Common Stock Sidus Space, Inc. We are offering 19,230,800 shares of our Class A common stock at a public offering price of $1.30 on a best efforts basis. We have engaged ThinkEquity LLC (the “placement agent”) to act as our exclusive placement agent in connection with this offering.The placement agent has agreed to use its reasonable best efforts to arrange for the sale of the securities offered by this prospectussupplement. The placement agent is not purchasing or selling any of the securities we are offering and the placement agent is notrequired to arrange the purchase or sale of any specific number or dollar amount of securities. We have agreed to pay placement agentfees to the placement agent as set forth in the table below, which assumes that we sell all of the securities offered by this prospectussupplement. Since we will deliver the securities to be issued in this offering upon our receipt of investor funds, there is no arrangementfor funds to be received in escrow, trust or similar arrangement. There is no minimum offering requirement as a condition of closing ofthis offering. Because there is no minimum offering amount required as a condition to closing this offering, we may sell fewer than allof the securities offered hereby, which may significantly reduce the amount of proceeds received by us, and investors in this offering Our Class A common stock is listed on The Nasdaq Capital Market under the symbol “SIDU”. On December 22, 2025, the closingprice as reported on The Nasdaq Capital Market was $2.285 per share. We are an “emerging growth company” as that term is used in the Jumpstart Our Business Startups Act of 2012 and, as such, haveelected to comply with certain reduced public company reporting requirements. Investing in our Class A common stock involves risks. See “Risk Factors” beginning on page S-11. Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of thesesecurities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense. (1)Does not include a non-accountable expense allowance of 1% of the gross proceeds. See “Plan of Distribution” beginning on pageS-15 of this prospectus supplement for additional information regarding placement agent fees and estimated expenses. The delivery of securities to purchasers on or about December 24, 2025, subject to the satisfaction of customary closing conditions. ThinkEquity The date of this prospectus supplement is December 22, 2025 TABLE OF CONTENTS PROSPECTUS SUPPLEMENT PROSPECTUS ABOUT THIS PROSPECTUS We incorporate by reference important information into this prospectus. You may obtain the information incorporated by referencewithout charge by following the instructions under “Where You Can Find More Information.” You should carefully read this Neither we nor the placement agent has authorized anyone to provide you with additional information or information different fromthat contained or incorporated by reference in this prospectus filed with the Securities and Exchange Commission (the “SEC”), andyou should rely only on the information contained in this prospectus or in any such free writing prospectus. We take no responsibilityfor and can provide no assurance as to the reliability of, any other information that others may give you. We and the placement agentare offering to sell, and seeking offers to buy, our securities only in jurisdictions where offers and sales are permitted. The informationcontained in this prospectus supplement, the accompanying prospectus or any document incorporated by reference in this prospectus The information incorporated by reference or provided in this prospectus supplement and accompanying prospectus contains estimatesand other statistical data made by independent parties and by us relating to market size and growth and other data about our industry.We obtained the industry and market data in this prospectus supplement from our own research as well as from industry and generalpublications, surveys and studies conducted by third parties. This data involves several assumptions and limitations and containsprojections and estimates of the future performance of the industries in which we operate that are subject to a high degree ofuncertainty, including those discussed in “Risk Factors.” We caution you not to give undue weight to such projections, assumptions,and estimates. Further, industry and general publications, studies and surveys generally state that they have been obtained from sources For investors outside the United States (“U.S.”): We and the placement agent have not done anything that would permit this offering orthe possession or distribution of this prospectus supplement in any jurisdiction where action for those purposes is required, other thanin the U.S. Persons outside the U.S. who come into possession of this prospectus supplement must inform