ASTRA SPACE, INC.

Primary Offering Of

15,333,303 Shares of Class A Common Stock

Secondary Offering of

189,026,575 Shares of Class A Common Stock

This prospectus supplement amends and supplements the prospectus dated August 12, 2021 (as supplemented or amended from time to time, the “Prospectus”), which forms a part of our Registration Statement on Form S-1 (No. 333-257930). This prospectus supplement is being filed to update and supplement the information in the Prospectus with the information contained in our Current Report on Form 8-K, filed with the Securities and Exchange Commission on March 23, 2022 (the “Current Report”). Accordingly, we have attached the Current Report to this prospectus supplement.

The Prospectus and this prospectus supplement also relate to the offer and sale, from time to time, by the selling securityholders named in this prospectus (the “Selling Securityholders”), or any of their permitted transferees, of (i) up to an aggregate of 20,000,000 shares of our Class A common stock that were issued to certain investors (collectively, the “PIPE Investors”) in a private placement in connection with the closing of the Business Combination (as defined herein); (ii) 7,500,000 shares of Class A common stock issued to the Sponsor prior to Holicity’s initial public offering and registered for sale by the Selling Securityholders; (iii) up to an aggregate of 92,277,793 shares of Class A common stock that were issued to certain affiliates of Astra (collectively, the “Astra Affiliates”) pursuant to the Business Combination Agreement (as defined herein); (iv) up to an aggregate 56,239,188 shares of Class A common stock issuable upon conversion (on a one-for-one basis) of shares of our Class B common stock, par value $0.0001 per share (“Class B Common Stock”) held by certain Selling Securityholders and (v) up to an aggregate of 7,676,261 shares of our Class A common stock issued in connection with our acquisition of Apollo Fusion, Inc. (“Apollo Fusion”), which closed on July 1, 2021 comprised of (x) 2,558,744 shares of our Class A common stock (the “Initial Apollo Shares”) issued to certain of the Selling Securityholders on July 1, 2021, in connection with our merger with Apollo Fusion, Inc. (“Apollo Fusion”) and (y) 5,117,517 additional shares of our Class A common stock (the “Additional Apollo Shares”) which may be issued to certain of the Selling Securityholders assuming (a) the achievement of all remaining performance milestones set forth in the Apollo Fusion Merger Agreement (as defined herein), (b) we elect to pay all future milestone consideration in shares of our Class A common stock as required by the terms the Apollo Fusion Merger Agreement, and (c) the per share price used to calculate the number of shares of our Class A common stock to be issued is $11.7243, which is the same per share price used to calculate the number of Initial Shares issued to the Selling Securityholders. The Additional Shares have not been earned and are not currently outstanding. The actual number of Additional Shares issued to the selling stockholders could be materially greater or less than 5,117,517 shares of Class A common stock depending whether and to what extent the future performance milestones are met and/or the actual average closing price of our Class A common stock at the time such milestones are achieved. The Prospectus and this prospectus supplement also cover any additional securities that may become issuable by reason of share splits, share dividends or other similar transactions.

Our Class A common stock is listed on Nasdaq under the symbol “ASTR”. On March 22, 2022, the closing price of our Class A common stock was $4.48 per share.

This prospectus supplement updates and supplements the information in the Prospectus and is not complete without, and may not be delivered or utilized except in combination with, the Prospectus, including any amendments or supplements thereto. This prospectus supplement should be read in conjunction with the Prospectus and if there is any inconsistency between the information in the Prospectus and this prospectus supplement, you should rely on the information in this prospectus supplement.

Investing in our securities involves risks that are described in the “Risk Factors” section beginning on page 15 of the Prospectus.

Neither the SEC nor any state securities commission has approved or disapproved of the securities to be issued under the Prospectus or determined if the Prospectus or this prospectus supplement is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus supplement is March 23, 2022.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): March 18, 2022

Astra Space, Inc.

(Exact name of Registrant as Specified in Its Charter)

Registrant’s Telephone Number, Including Area Code: (866) 278-7217

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company  ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 4.01 Changes in Registrant’s Certifying Accountant.

(a) Dismissal of Previous Independent Registered Public Accounting Firm.

On March 18, 2022, the audit committee (the “Audit Committee”) of the Board of Directors of Astra Space, Inc. (the “Company”) dismissed Grant Thornton LLP (“Grant Thornton”) as the Company’s independent registered public accounting firm. Grant Thornton was previously engaged to audit the Company’s consolidated financial statements for the year ended December 31, 2021. The dismissal does not affect Grant Thornton’s engagement for the year ended December 31, 2021.

As described below, the change in independent registered public accounting firm is not the result of any disagreement with Grant Thornton. Grant Thornton has served as the Company’s independent registered public accounting firm since its business combination with Astra Space Operations, Inc. (f/k/a Astra Space, Inc.) (“Legacy Astra”) on June 30, 2021, and it served as Legacy Astra’s independent registered public accounting firm since the fourth quarter of 2020 and performed audits of Legacy Astra’s financial statements for the fiscal years ended December 31, 2019 and 2020.

Grant Thornton’s audit reports on the financial statements for the fiscal years ended December 31, 2019 and 2020 did not provide an adverse opinion or disclaimer of opinion to the Company’s financial statements, nor modify its opinion as to uncertainty, audit scope or accounting principles, except that Grant Thornton’s audit reports for the fiscal years ended December 31, 2019 and 2020 included a statement of substantial doubt about the Company’s ability to continue as a going concern.

During the fiscal years ended December 31, 2019 and 2020 and through March 18, 2022, there were no “disagreements” within the meaning of Item 304(a)(1)(iv) of Regulation S-K and the related instructions between the Company and Grant Thornton on any matters of accounting principles or practices, financial statement disclosures or auditing scope or procedures which, if not resolved to Grant Thornton’s satisfaction, would have caused Grant Thornton to make reference thereto in its reports on the financial statements of the Company for such years.

During the fiscal years ended December 31, 2019 and 2020 and the interim period through March 18, 2022, there were no “reportable events” (as that term is defined in Item 304(a)(1)(v) of Regulation S-K), other than the material weaknesses identified in our public reports for the fiscal years ended December 31, 2020 and 2019, and for the nine months ended September 30, 2021.

The Company provided Grant Thornton with a copy of the disclosure it is making herein in response to Item 304(a) of Regulation S-K and requested that Grant Thornton furnish the Company with a copy of their letter addressed to the Securities and Exchange Commission (the “SEC”) pursuant to Item 304(a)(3) of Regulation S-K, stating whether Grant Thornton agrees with the statements made by the Company in this Current Report on Form 8-K in response to Item 304(a) of Regulation S-K. A copy of Grant Thornton’s letter to the SEC dated March 23, 2022 is attached as Exhibit 16.1 to this Current Report on Form 8-K.

(b) Engagement of New Independent Registered Public Accounting Firm.

On March 18, 2022, the Audit Committee approved the engagement of PricewaterhouseCoopers, LLP (“PwC”) as the Company’s new independent registered public accounting firm for the Company’s fiscal year ending December 31, 2022, subject to PwC’s completion of its client acceptance procedures.

During the fiscal years ended December 31, 2019 and 2020 and through March 18, 2022, neither the Company, nor anyone on its behalf, consulted PwC regarding either (i) the application of accounting principles to a specified transaction, either completed or proposed, or the type of audit opinion that might be rendered on the financial statements of the Company, and neither a written report nor oral advice was provided to the Company that PwC concluded was an important factor considered by the Company in reaching a decision as to any accounting, auditing or financial reporting issue; or (ii) any matter that was the subject of a “disagreement” (as defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions) or a “reportable event” (as described in Item 304(a)(1)(v) of Regulation S-K).

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

Exhibit 16.1

March 23, 2022

U.S. Securities and Exchange Commission

Office of the Chief Accountant

100 F Street, NE

Washington, DC 20549

Re: Astra Space, Inc.

File No. 001-39426

Dear Sir or Madam:

We have read Item 4.01 of Form 8-K of Astra Space, Inc. dated March 23, 2022, and agree with the statements concerning our Firm contained therein.

Very truly yours,

/s/ GRANT THORNTON LLP