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  <xs:element id="mnts_CommonAndPreferredStockSharesAuthorized" abstract="false" name="CommonAndPreferredStockSharesAuthorized" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_InducementWarrantsMember" abstract="true" name="InducementWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightOfferingFeesAndOtherExpensesPayable" abstract="false" name="ClassOfWarrantOrRightOfferingFeesAndOtherExpensesPayable" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_PreFundedWarrantsMember" abstract="true" name="PreFundedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_CommonWarrantMember" abstract="true" name="CommonWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_December2024PurchaseAgreementMember" abstract="true" name="December2024PurchaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_SeptemberPrefundedWarrantsMember" abstract="true" name="SeptemberPrefundedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_PlacementAgentWarrantsMember" abstract="true" name="PlacementAgentWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_February2025PublicOfferingMember" abstract="true" name="February2025PublicOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_OfferingPricePerShareForWarrants" abstract="false" name="OfferingPricePerShareForWarrants" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="mnts_SaleOfStockNotEnteringAdditionalAgreementsPeriod" abstract="false" name="SaleOfStockNotEnteringAdditionalAgreementsPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_SaleOfStockPlacementAgentCashFeePercentageOfGrossProceeds" abstract="false" name="SaleOfStockPlacementAgentCashFeePercentageOfGrossProceeds" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_SaleOfStockEstimatedIssuanceCosts" abstract="false" name="SaleOfStockEstimatedIssuanceCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightGrossProceedsAndIssuedWarrantsCommissionPercentage" abstract="false" name="ClassOfWarrantOrRightGrossProceedsAndIssuedWarrantsCommissionPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_WarrantsAndRightsOutstandingExerciseTermAfterIssuance" abstract="false" name="WarrantsAndRightsOutstandingExerciseTermAfterIssuance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_WarrantsAndRightsOutstandingFirstTerm" abstract="false" name="WarrantsAndRightsOutstandingFirstTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_WarrantsAndRightsOutstandingSecondTerm" abstract="false" name="WarrantsAndRightsOutstandingSecondTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_StockIssuedDuringPeriodShareIssuedInConnectionWithCashlessExercise" abstract="false" name="StockIssuedDuringPeriodShareIssuedInConnectionWithCashlessExercise" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_MarchPreFundedWarrantsMember" abstract="true" name="MarchPreFundedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_MarchWarrantsMember" abstract="true" name="MarchWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_JanuaryWarrantsMember" abstract="true" name="JanuaryWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_JanuaryPreFundedWarrantsMember" abstract="true" name="JanuaryPreFundedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_NovemberModifiedWarrantsMember" abstract="true" name="NovemberModifiedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_PrivateWarrantMember" abstract="true" name="PrivateWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_ContingentSponsorEarnoutSharesMember" abstract="true" name="ContingentSponsorEarnoutSharesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_WeightedAverageClosingPriceAxis" abstract="true" name="WeightedAverageClosingPriceAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="mnts_WeightedAverageClosingPriceDomain" abstract="true" name="WeightedAverageClosingPriceDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_WeightedAverageClosingPriceTrancheOneMember" abstract="true" name="WeightedAverageClosingPriceTrancheOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_WeightedAverageClosingPriceTrancheTwoMember" abstract="true" name="WeightedAverageClosingPriceTrancheTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_WeightedAverageClosingPriceTrancheThreeMember" abstract="true" name="WeightedAverageClosingPriceTrancheThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1: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_ShareBasedPaymentArrangementWeightedAverageClosingPrice" abstract="false" name="ShareBasedPaymentArrangementWeightedAverageClosingPrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="mnts_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesForfeitedPercentage" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesForfeitedPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="mnts_A2021EquityIncentivePlanMember" abstract="true" name="A2021EquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_A2021EmployeeStockPurchasePlanMember" abstract="true" name="A2021EmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_A2022InducementEquityPlanMember" abstract="true" name="A2022InducementEquityPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_OutstandingVestedAndExpectedToVestRSUsMember" abstract="true" name="OutstandingVestedAndExpectedToVestRSUsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_ShareBasedPaymentArrangementEvergreenProvisionPercentageOfOutstandingShares" abstract="false" name="ShareBasedPaymentArrangementEvergreenProvisionPercentageOfOutstandingShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="mnts_AccruedEmployeeBenefitsEmployeeStockPurchasePlan" abstract="false" name="AccruedEmployeeBenefitsEmployeeStockPurchasePlan" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_RestrictedStockUnitsAndRestrictedStockAwardsMember" abstract="true" name="RestrictedStockUnitsAndRestrictedStockAwardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_ShareBasedPaymentArrangementOptionsAndUnvestedStockUnitsMember" abstract="true" name="ShareBasedPaymentArrangementOptionsAndUnvestedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_BakerMckenzieMember" abstract="true" name="BakerMckenzieMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_NationalSecurityAgreementMember" abstract="true" name="NationalSecurityAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_SAFENoteLitigationMember" abstract="true" name="SAFENoteLitigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_StephenJPurcellMember" abstract="true" name="StephenJPurcellMember" 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_ReverseRecapitalizationConsiderationTypeDomain" abstract="true" name="ReverseRecapitalizationConsiderationTypeDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_ConsiderationDueWithin10BusinessDaysMember" abstract="true" name="ConsiderationDueWithin10BusinessDaysMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationPercentageOfVotingInterestsAcquired" abstract="false" name="ReverseRecapitalizationPercentageOfVotingInterestsAcquired" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <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_ReverseRecapitalizationContingentConsiderationEquityEarnoutPeriodThresholdBusinessDays" abstract="false" name="ReverseRecapitalizationContingentConsiderationEquityEarnoutPeriodThresholdBusinessDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_ProceedsFromSaleOfBusinessAndOtherCapitalRaisingTransactionsMinimum" abstract="false" name="ProceedsFromSaleOfBusinessAndOtherCapitalRaisingTransactionsMinimum" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_LitigationSettlementReformsMaintainedForAMinimumPeriod" abstract="false" name="LitigationSettlementReformsMaintainedForAMinimumPeriod" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_LossContingencyAllegedInvestmentAmount" abstract="false" name="LossContingencyAllegedInvestmentAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DirectorsAndOfficersMember" abstract="true" name="DirectorsAndOfficersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_NumberOfPromissoryNotes" abstract="false" name="NumberOfPromissoryNotes" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_PurchasesOfIntangiblesAssetsDuringNoncashOrPartialNoncashTransactionIncludedInAccountsPayableAndAccruedExpenses" abstract="false" name="PurchasesOfIntangiblesAssetsDuringNoncashOrPartialNoncashTransactionIncludedInAccountsPayableAndAccruedExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_IssuanceOfCommonStockUponPartialConversionOfConvertibleNote" abstract="false" name="IssuanceOfCommonStockUponPartialConversionOfConvertibleNote" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtInstrumentConvertibleConversionLimitationPercent" abstract="false" name="DebtInstrumentConvertibleConversionLimitationPercent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
