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                          May 8, 2024

       Virginia Johnson
       Chief Legal Officer
       Aspen Aerogels, Inc.
       30 Forbes Road, Building B
       Northborough, Massachusetts 01532

                                                        Re: Aspen Aerogels, 
Inc.
                                                            Registration 
Statement on Form S-3
                                                            Filed May 2, 2024
                                                            File No. 333-279072

       Dear Virginia Johnson:

              This is to advise you that we have not reviewed and will not 
review your registration
       statement.

               Please refer to Rules 460 and 461 regarding requests for 
acceleration. We remind you
       that the company and its management are responsible for the accuracy and 
adequacy of their
       disclosures, notwithstanding any review, comments, action or absence of 
action by the staff.

                                                        Please contact Jenna 
Hough at 202-551-3063 with any questions.



                                                                                
                          Sincerely,

                                                                                
                          Division of Corporation Finance
                                                                                
                          Office of Trade & Services
       cc:                                              Nishant Dharia