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  <xs:element id="mnts_LegacyStockPlanMember" abstract="true" name="LegacyStockPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationInitialConsiderationTransferredToEachCoFounder" abstract="false" name="ReverseRecapitalizationInitialConsiderationTransferredToEachCoFounder" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_NumberOfLaunchServiceAgreementsTerminated" abstract="false" name="NumberOfLaunchServiceAgreementsTerminated" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_ContractWithCustomerLiabilityRevenueRecognizedDueToUncertainties" abstract="false" name="ContractWithCustomerLiabilityRevenueRecognizedDueToUncertainties" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_EquipmentLoanMember" abstract="true" name="EquipmentLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_A2022InducementEquityPlanMember" abstract="true" name="A2022InducementEquityPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_PrivateInvestmentInPublicEquityInvestorsMember" abstract="true" name="PrivateInvestmentInPublicEquityInvestorsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationProceedsReceivedFromShareholders" abstract="false" name="ReverseRecapitalizationProceedsReceivedFromShareholders" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationTransactionCosts" abstract="false" name="ReverseRecapitalizationTransactionCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_OtherWarrantsMember" abstract="true" name="OtherWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ScheduleOfReverseRecapitalizationTable" abstract="true" name="ScheduleOfReverseRecapitalizationTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="mnts_NumberOfCustomerSatellites" abstract="false" name="NumberOfCustomerSatellites" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationContingentConsiderationEquityNonTransferPeriodThresholdConsecutiveTradingDays" abstract="false" name="ReverseRecapitalizationContingentConsiderationEquityNonTransferPeriodThresholdConsecutiveTradingDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_PrepaidResearchAndDevelopmentExpenseCurrent" abstract="false" name="PrepaidResearchAndDevelopmentExpenseCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightPreferredStockAvailableToBeCalledPercentageEarned" abstract="false" name="ClassOfWarrantOrRightPreferredStockAvailableToBeCalledPercentageEarned" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_NumberOfThirdPartyCustomerSatellitesDeployedInLowEarthOrbit" abstract="false" name="NumberOfThirdPartyCustomerSatellitesDeployedInLowEarthOrbit" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" abstract="false" name="FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationNetProceedsReceivedFromShareholders" abstract="false" name="ReverseRecapitalizationNetProceedsReceivedFromShareholders" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_CommonAndPreferredStockSharesAuthorized" abstract="false" name="CommonAndPreferredStockSharesAuthorized" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_CashDesignatedForCollateralMember" abstract="true" name="CashDesignatedForCollateralMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationConsiderationTypeAxis" abstract="true" name="ReverseRecapitalizationConsiderationTypeAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="mnts_PrepaidLaunchCostsImpairment" abstract="false" name="PrepaidLaunchCostsImpairment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_WeightedAverageClosingPriceTrancheTwoMember" abstract="true" name="WeightedAverageClosingPriceTrancheTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ShareBasedPaymentArrangementNumberOfSharesModified" abstract="false" name="ShareBasedPaymentArrangementNumberOfSharesModified" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_PrepaidLaunchCostsNoncurrent" abstract="false" name="PrepaidLaunchCostsNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_PaymentsOfReverseRecapitalizationTransactionCosts" abstract="false" name="PaymentsOfReverseRecapitalizationTransactionCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationPaymentsToCoFounders" abstract="false" name="ReverseRecapitalizationPaymentsToCoFounders" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_PaymentOfWarrantIssuanceCosts" abstract="false" name="PaymentOfWarrantIssuanceCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationPercentageOfVotingInterestsSold" abstract="false" name="ReverseRecapitalizationPercentageOfVotingInterestsSold" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationContingentConsiderationEquityNonTransferPeriodThresholdTradingDays" abstract="false" name="ReverseRecapitalizationContingentConsiderationEquityNonTransferPeriodThresholdTradingDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_StableRoadAcquisitionCorporationAndAffiliatesMember" abstract="true" name="StableRoadAcquisitionCorporationAndAffiliatesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_StockIssuedDuringPeriodValueConversionOfSAFENotes" abstract="false" name="StockIssuedDuringPeriodValueConversionOfSAFENotes" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ProceedsFromSaleOfBusinessAndOtherCapitalRaisingTransactionsFromCoFoundersMinimum" abstract="false" name="ProceedsFromSaleOfBusinessAndOtherCapitalRaisingTransactionsFromCoFoundersMinimum" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationContingentConsiderationEquityNonTransferPeriod" abstract="false" name="ReverseRecapitalizationContingentConsiderationEquityNonTransferPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_NumberOfLaunchAgreementsTerminated" abstract="false" name="NumberOfLaunchAgreementsTerminated" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightPreferredStockAvailableToBeCalledPercentageForfeited" abstract="false" name="ClassOfWarrantOrRightPreferredStockAvailableToBeCalledPercentageForfeited" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_DebtInstrumentDiscountRateInExcessOfInitialFaceValuePercentage" abstract="false" name="DebtInstrumentDiscountRateInExcessOfInitialFaceValuePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_MomentusSpaceLLCUnitHoldersMember" abstract="true" name="MomentusSpaceLLCUnitHoldersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_May222021StockOptionModificationsMember" abstract="true" name="May222021StockOptionModificationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationPublicInvestment" abstract="false" name="ReverseRecapitalizationPublicInvestment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_January252021StockOptionModificationMember" abstract="true" name="January252021StockOptionModificationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_StockIssuedDuringPeriodValueSection16OfficerTaxCoverageExchange" abstract="false" name="StockIssuedDuringPeriodValueSection16OfficerTaxCoverageExchange" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ShareBasedPaymentArrangementWeightedAverageClosingPrice" abstract="false" name="ShareBasedPaymentArrangementWeightedAverageClosingPrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="mnts_PaymentsOfStockIssuanceCostsRelatedToPrivatePlacement" abstract="false" name="PaymentsOfStockIssuanceCostsRelatedToPrivatePlacement" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationPercentageOfVotingInterestsAcquired" abstract="false" name="ReverseRecapitalizationPercentageOfVotingInterestsAcquired" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_StockIssuedDuringPeriodSharesConversionOfSAFENotes" abstract="false" name="StockIssuedDuringPeriodSharesConversionOfSAFENotes" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_ConversionOfSimpleAgreementForFutureEquityIssuanceToCommonStock" abstract="false" name="ConversionOfSimpleAgreementForFutureEquityIssuanceToCommonStock" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ContractWithCustomerLiabilityVariableConsideration" abstract="false" name="ContractWithCustomerLiabilityVariableConsideration" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_PrepaidLaunchCostsImpairmentCharges" abstract="false" name="PrepaidLaunchCostsImpairmentCharges" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_SaleOfStockCompensationAtCommissionRatePercentage" abstract="false" name="SaleOfStockCompensationAtCommissionRatePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_CommonStockPercentageOfOwnershipAfterReverseRecapitalization" abstract="false" name="CommonStockPercentageOfOwnershipAfterReverseRecapitalization" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_UnrecordedUnconditionalPurchaseObligationToBePaidAfterYearThree" abstract="false" name="UnrecordedUnconditionalPurchaseObligationToBePaidAfterYearThree" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_WeightedAverageClosingPriceTrancheThreeMember" abstract="true" name="WeightedAverageClosingPriceTrancheThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightPercentageOfPreferredStockAvailableToBeCalled" abstract="false" name="ClassOfWarrantOrRightPercentageOfPreferredStockAvailableToBeCalled" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
