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  <xs:element id="mnts_AdjustmentsToAdditionalPaidInCapitalWarrantIssuedLoanPayable" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalWarrantIssuedLoanPayable" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_StockIssuedDuringPeriodSharesCommonSharesAndPreFundedWarrantsInSettlementOfAccountsPayableAndCustomerDeposits" abstract="false" name="StockIssuedDuringPeriodSharesCommonSharesAndPreFundedWarrantsInSettlementOfAccountsPayableAndCustomerDeposits" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_StockIssuedDuringPeriodValueCommonSharesAndPreFundedWarrantsInSettlementOfAccountsPayableAndCustomerDeposits" abstract="false" name="StockIssuedDuringPeriodValueCommonSharesAndPreFundedWarrantsInSettlementOfAccountsPayableAndCustomerDeposits" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_StockIssuedDuringPeriodSharesConversionOfConvertibleNotePrincipalAndInterest" abstract="false" name="StockIssuedDuringPeriodSharesConversionOfConvertibleNotePrincipalAndInterest" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_StockIssuedDuringPeriodValueConversionOfConvertibleNotePrincipalAndInterest" abstract="false" name="StockIssuedDuringPeriodValueConversionOfConvertibleNotePrincipalAndInterest" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_AdjustmentsToAdditionalPaidInCapitalWarrantsIssuedWithConvertibleDebtExtinguishments" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalWarrantsIssuedWithConvertibleDebtExtinguishments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_AdjustmentsToAdditionalPaidInCapitalWarrantsIssuedWithConvertibleDebt" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalWarrantsIssuedWithConvertibleDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_AdjustmentsToAdditionalPaidInCapitalWarrantsIssuedDebtIssuanceCosts" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalWarrantsIssuedDebtIssuanceCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ImpairmentOfPrepaidServices" abstract="false" name="ImpairmentOfPrepaidServices" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtIssuanceCostsExpensedForConvertibleDebtCarriedAtFairValue" abstract="false" name="DebtIssuanceCostsExpensedForConvertibleDebtCarriedAtFairValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_GainLossOnIssuanceOfWarrantLiabilities" abstract="false" name="GainLossOnIssuanceOfWarrantLiabilities" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_IssuanceOfConvertibleNotesForLegalServices" abstract="false" name="IssuanceOfConvertibleNotesForLegalServices" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_IncreaseDecreaseInLitigationSettlementContingency" abstract="false" name="IncreaseDecreaseInLitigationSettlementContingency" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DeferredFulfillmentAndPrepaidLaunchCostsPolicyTextBlock" abstract="false" name="DeferredFulfillmentAndPrepaidLaunchCostsPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="mnts_WarrantLiabilitiesPolicyTextBlock" abstract="false" name="WarrantLiabilitiesPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="mnts_EquityClassifiedWarrantsPolicyPolicyTextBlock" abstract="false" name="EquityClassifiedWarrantsPolicyPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="mnts_ModificationOfEquityClassifiedWarrantsPolicyPolicyTextBlock" abstract="false" name="ModificationOfEquityClassifiedWarrantsPolicyPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="mnts_ConvertibleInstrumentsPolicyPolicyTextBlock" abstract="false" name="ConvertibleInstrumentsPolicyPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="mnts_ScheduleOfReverseRecapitalizationTable" abstract="true" name="ScheduleOfReverseRecapitalizationTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="mnts_ScheduleOfReverseRecapitalizationLineItems" abstract="true" name="ScheduleOfReverseRecapitalizationLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="mnts_NumberOfSpacecraftMissions" abstract="false" name="NumberOfSpacecraftMissions" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_NumberOfCustomerSatellitesDeployedInOrbit" abstract="false" name="NumberOfCustomerSatellitesDeployedInOrbit" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_NumberOfSpacecraftMissionsInOrbit" abstract="false" name="NumberOfSpacecraftMissionsInOrbit" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <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_ELOCPreFundedWarrantsMember" abstract="true" name="ELOCPreFundedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_PrivatePlacementWarrantMember" abstract="true" name="PrivatePlacementWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_PublicWarrantMember" abstract="true" name="PublicWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_DeferredFulfillmentAndPrepaidLaunchCosts" abstract="false" name="DeferredFulfillmentAndPrepaidLaunchCosts" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ContractWithCustomerLiabilityRevenueRecognizedExcludingOpeningBalance" abstract="false" name="ContractWithCustomerLiabilityRevenueRecognizedExcludingOpeningBalance" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_RecapitalizationExchangeRatio" abstract="false" name="RecapitalizationExchangeRatio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightExpirationPeriod" abstract="false" name="ClassOfWarrantOrRightExpirationPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_ShareBasedCompensationArrangementByShareBasedPaymentAwardStockPlanOfferingPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardStockPlanOfferingPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_ForfeitedCustomerDepositsMember" abstract="true" name="ForfeitedCustomerDepositsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_EngineeringProjectServicesMember" abstract="true" name="EngineeringProjectServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_MayLoanAgreementMember" abstract="true" name="MayLoanAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_May2025ConvertibleNoteMember" abstract="true" name="May2025ConvertibleNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_AIRWarrantsMember" abstract="true" name="AIRWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_CreditProvisionDerivativeAssetMember" abstract="true" name="CreditProvisionDerivativeAssetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityExtinguishment" abstract="false" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityExtinguishment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityExercise" abstract="false" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityExercise" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_UnderlyingInvestorWarrantsBSMMember" abstract="true" name="UnderlyingInvestorWarrantsBSMMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_JuniorConvertibleNotesMember" abstract="true" name="JuniorConvertibleNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_PrepaidLaunchCostsCurrent" abstract="false" name="PrepaidLaunchCostsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_PrepaidDesignAndProductionServicesCurrent" abstract="false" name="PrepaidDesignAndProductionServicesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_PrepaidInsuranceAndOtherAssetsCurrent" abstract="false" name="PrepaidInsuranceAndOtherAssetsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_PrepaidDesignAndProductionServicesNoncurrent" abstract="false" name="PrepaidDesignAndProductionServicesNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_PrepaidDesignAndProductionServicesImpairmentCharges" abstract="false" name="PrepaidDesignAndProductionServicesImpairmentCharges" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_AccruedResearchAndDevelopmentExpensesCurrent" abstract="false" name="AccruedResearchAndDevelopmentExpensesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_September2025ConvertibleNoteMember" abstract="true" name="September2025ConvertibleNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_DebtInstrumentDerivativeLiabilityFairValue" abstract="false" name="DebtInstrumentDerivativeLiabilityFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtInstrumentConvertibleDiscountPercentage" abstract="false" name="DebtInstrumentConvertibleDiscountPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_DebtInstrumentPrepaymentFeePercentage" abstract="false" name="DebtInstrumentPrepaymentFeePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightExerciseAmountAverageDailyTradingVolumeMultiple" abstract="false" name="ClassOfWarrantOrRightExerciseAmountAverageDailyTradingVolumeMultiple" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightExerciseAmountAverageTradingPricePeriod" abstract="false" name="ClassOfWarrantOrRightExerciseAmountAverageTradingPricePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightBeneficiallyOwnedToExceedPercentage" abstract="false" name="ClassOfWarrantOrRightBeneficiallyOwnedToExceedPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_InitialTrancheWarrantsMember" abstract="true" name="InitialTrancheWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_SecondTrancheWarrantsMember" abstract="true" name="SecondTrancheWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_September2025SIVWarrantsMember" abstract="true" name="September2025SIVWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_DecemberLoanAgreementMember" abstract="true" name="DecemberLoanAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_SIVConvertiblePromissoryNotesMember" abstract="true" name="SIVConvertiblePromissoryNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_SIVModifiedWarrantsMember" abstract="true" name="SIVModifiedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_J.J.AstorCo.WarrantsMember" abstract="true" name="J.J.AstorCo.WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_DebtInstrumentNumberOfTranches" abstract="false" name="DebtInstrumentNumberOfTranches" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_DebtInstrumentAdditionalAmount" abstract="false" name="DebtInstrumentAdditionalAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtInstrumentInitialPrincipalAmount" abstract="false" name="DebtInstrumentInitialPrincipalAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtInstrumentNumberOfWeeklyPeriodicPayments" abstract="false" name="DebtInstrumentNumberOfWeeklyPeriodicPayments" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_DebtInstrumentPeriodicPaymentPercentageInCash" abstract="false" name="DebtInstrumentPeriodicPaymentPercentageInCash" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_DebtInstrumentConvertibleNumberOfVolumeWeightedAverageClosingPrices" abstract="false" name="DebtInstrumentConvertibleNumberOfVolumeWeightedAverageClosingPrices" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_ClassOfWarrantsOrRightAdditionalDebtIssuanceCosts" abstract="false" name="ClassOfWarrantsOrRightAdditionalDebtIssuanceCosts" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtInstrumentMarketCapitalizationValue" abstract="false" name="DebtInstrumentMarketCapitalizationValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtInstrumentTerminationFeeAmount" abstract="false" name="DebtInstrumentTerminationFeeAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtInstrumentFirstPrepaymentAmount" abstract="false" name="DebtInstrumentFirstPrepaymentAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_AGPConvertiblePromissoryNotesMember" abstract="true" name="AGPConvertiblePromissoryNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_DebtInstrumentSecondPrepaymentAmount" abstract="false" name="DebtInstrumentSecondPrepaymentAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_OctoberSIVWarrantsAndDecemberSIVWarrantsMember" abstract="true" name="OctoberSIVWarrantsAndDecemberSIVWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_September2025AmendmentMember" abstract="true" name="September2025AmendmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_OctoberConvertibleNoteMember" abstract="true" name="OctoberConvertibleNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_DebtInstrumentNumberOfPeriodicPayments" abstract="false" name="DebtInstrumentNumberOfPeriodicPayments" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_DebtInstrumentPrepaymentPenaltyFee" abstract="false" name="DebtInstrumentPrepaymentPenaltyFee" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_DebtInstrumentConvertiblePeriodAfterOriginalIssuanceToStartConversion" abstract="false" name="DebtInstrumentConvertiblePeriodAfterOriginalIssuanceToStartConversion" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_DebtInstrumentCapitalExpenditures" abstract="false" name="DebtInstrumentCapitalExpenditures" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_AdditionalGainLossOnExtinguishmentOfDebt" abstract="false" name="AdditionalGainLossOnExtinguishmentOfDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtInstrumentInterestRateAmortizationOfPremiumEffectivePercentage" abstract="false" name="DebtInstrumentInterestRateAmortizationOfPremiumEffectivePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_PostponedRepaymentsOfConvertibleDebt" abstract="false" name="PostponedRepaymentsOfConvertibleDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_PostponedPrincipalRepaymentsOfConvertibleDebt" abstract="false" name="PostponedPrincipalRepaymentsOfConvertibleDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_PostponedInterestRepaymentsOfConvertibleDebt" abstract="false" name="PostponedInterestRepaymentsOfConvertibleDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtInstrumentConvertibleConversionDiscountRate" abstract="false" name="DebtInstrumentConvertibleConversionDiscountRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_DebtInstrumentAccordionFeatureIncreaseLimit" abstract="false" name="DebtInstrumentAccordionFeatureIncreaseLimit" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtInstrumentAccordionFeatureIssuanceOfWarrantsToPurchaseSharesPercent" abstract="false" name="DebtInstrumentAccordionFeatureIssuanceOfWarrantsToPurchaseSharesPercent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_DebtConversionCashCommitmentToInvestor" abstract="false" name="DebtConversionCashCommitmentToInvestor" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DebtInstrumentAccruedInterest" abstract="false" name="DebtInstrumentAccruedInterest" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_TermLoanMember" abstract="true" name="TermLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_DebtInstrumentReductionInFaceAmount" abstract="false" name="DebtInstrumentReductionInFaceAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_CommonAndPreferredStockSharesAuthorized" abstract="false" name="CommonAndPreferredStockSharesAuthorized" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_SettlementOfAccountsPayableFromIssuanceOfStock" abstract="false" name="SettlementOfAccountsPayableFromIssuanceOfStock" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_December2025WarrantInducementMember" abstract="true" name="December2025WarrantInducementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_December2025WarrantsMember" abstract="true" name="December2025WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_PreModificationWarrantMember" abstract="true" name="PreModificationWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_PostModificationWarrantMember" abstract="true" name="PostModificationWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_March2025WarrantsMember" abstract="true" name="March2025WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_July2025WarrantsMember" abstract="true" name="July2025WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_October2025WarrantsMember" abstract="true" name="October2025WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_December2024WolverineWarrantsMember" abstract="true" name="December2024WolverineWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_February2025WarrantsMember" abstract="true" name="February2025WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_InvestorModifiedWarrantsMember" abstract="true" name="InvestorModifiedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_August2025WarrantsMember" abstract="true" name="August2025WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_December2024WarrantsMember" abstract="true" name="December2024WarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_December2024PlacementAgentWarrantsMember" abstract="true" name="December2024PlacementAgentWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_September2024PlacementAgentWarrantsMember" abstract="true" name="September2024PlacementAgentWarrantsMember" 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_MeasurementInputExercisePriceBeforeRepricingMember" abstract="true" name="MeasurementInputExercisePriceBeforeRepricingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_MeasurementInputExercisePriceAfterRepricingMember" abstract="true" name="MeasurementInputExercisePriceAfterRepricingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_December2025WarrantInducementImmediatelyExercisableMember" abstract="true" name="December2025WarrantInducementImmediatelyExercisableMember" 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_October2025WarrantInducementMember" abstract="true" name="October2025WarrantInducementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_October2025WarrantInducementImmediatelyExercisableMember" abstract="true" name="October2025WarrantInducementImmediatelyExercisableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_JulyInducementWarrantsImmediatelyExercisableMember" abstract="true" name="JulyInducementWarrantsImmediatelyExercisableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightWarrantsExercised" abstract="false" name="ClassOfWarrantOrRightWarrantsExercised" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_BMPreFundedWarrantsMember" abstract="true" name="BMPreFundedWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_BakerMcKenzieLLPMember" abstract="true" name="BakerMcKenzieLLPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_SettlementAgreementObligationAmount" abstract="false" name="SettlementAgreementObligationAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_SettlementAgreementObligationAmountPaidInCash" abstract="false" name="SettlementAgreementObligationAmountPaidInCash" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_SettlementAgreementAdditionalExpenseRecognized" abstract="false" name="SettlementAgreementAdditionalExpenseRecognized" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_SaleOfStockPendingConsiderationOnTransaction" abstract="false" name="SaleOfStockPendingConsiderationOnTransaction" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_SaleOfStockCovenantTradingPricePercentageOfPurchasePrice" abstract="false" name="SaleOfStockCovenantTradingPricePercentageOfPurchasePrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_SaleOfStockTerm" abstract="false" name="SaleOfStockTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_SaleOfStockOptionalTerm" abstract="false" name="SaleOfStockOptionalTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRightsIfTerminated" abstract="false" name="ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRightsIfTerminated" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_NumberOfTradingDays" abstract="false" name="NumberOfTradingDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_ATMSalesAgreementMember" abstract="true" name="ATMSalesAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_SaleOfStockCompensationAtCommissionRateOfGrossSalesPercentage" abstract="false" name="SaleOfStockCompensationAtCommissionRateOfGrossSalesPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_August2025WarrantInducementMember" abstract="true" name="August2025WarrantInducementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_August2025WarrantInducementImmediatelyExercisableMember" abstract="true" name="August2025WarrantInducementImmediatelyExercisableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantOrRightsPercentageOfSharesIssuedUponExercise" abstract="false" name="ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantOrRightsPercentageOfSharesIssuedUponExercise" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <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_July2025PublicOfferingMember" abstract="true" name="July2025PublicOfferingMember" 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_Velo3DInc.Member" abstract="true" name="Velo3DInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ManufacturingServiceAgreementTerm" abstract="false" name="ManufacturingServiceAgreementTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_ManufacturingServiceAgreementAnnualManufacturingCapacityEquivalent" abstract="false" name="ManufacturingServiceAgreementAnnualManufacturingCapacityEquivalent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ManufacturingServiceAgreementNumberOfPrintersOrEquipmentUsedAnnually" abstract="false" name="ManufacturingServiceAgreementNumberOfPrintersOrEquipmentUsedAnnually" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_ManufacturingServiceAgreementCreditsOfUnusedValueOfManufacturingCapacityRemainderOfYearPercent" abstract="false" name="ManufacturingServiceAgreementCreditsOfUnusedValueOfManufacturingCapacityRemainderOfYearPercent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_ManufacturingServiceAgreementCreditsOfUnusedValueOfManufacturingCapacityThereafterPercent" abstract="false" name="ManufacturingServiceAgreementCreditsOfUnusedValueOfManufacturingCapacityThereafterPercent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_ManufacturingServiceAgreementOptionToPurchaseEquipmentAtAmortizedValuePercent" abstract="false" name="ManufacturingServiceAgreementOptionToPurchaseEquipmentAtAmortizedValuePercent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_ManufacturingServiceAgreementAssumptionsOnADiscountForLackOfMarketabilityVolatilityRate" abstract="false" name="ManufacturingServiceAgreementAssumptionsOnADiscountForLackOfMarketabilityVolatilityRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_ManufacturingServiceAgreementAssumptionsOnADiscountForLackOfMarketabilityHoldingRestrictionPeriod" abstract="false" name="ManufacturingServiceAgreementAssumptionsOnADiscountForLackOfMarketabilityHoldingRestrictionPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_ShareBasedCompensationArrangementByShareBasedPaymentAwardWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ManufacturingServiceAgreementAmountReceivedOnAnnualPrepayment" abstract="false" name="ManufacturingServiceAgreementAmountReceivedOnAnnualPrepayment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ManufacturingServiceAgreementPrepaidServiceAmount" abstract="false" name="ManufacturingServiceAgreementPrepaidServiceAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_March2025WarrantInducementMember" abstract="true" name="March2025WarrantInducementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_PlacementAgentWarrantsMember" abstract="true" name="PlacementAgentWarrantsMember" 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_February2025PublicOfferingMember" abstract="true" name="February2025PublicOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_December2024PurchaseAgreementMember" abstract="true" name="December2024PurchaseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_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_ContingentSponsorEarnoutSharesMember" abstract="true" name="ContingentSponsorEarnoutSharesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types: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-types:domainItemType"/>
  <xs:element id="mnts_WeightedAverageClosingPriceTrancheOneMember" abstract="true" name="WeightedAverageClosingPriceTrancheOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_WeightedAverageClosingPriceTrancheThreeMember" abstract="true" name="WeightedAverageClosingPriceTrancheThreeMember" 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_ShareBasedPaymentArrangementWeightedAverageClosingPrice" abstract="false" name="ShareBasedPaymentArrangementWeightedAverageClosingPrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="mnts_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesForfeitedPercentage" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesForfeitedPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="mnts_A2021EquityIncentivePlanMember" abstract="true" name="A2021EquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_A2021EquityIncentivePlanEvergreenProvisionMember" abstract="true" name="A2021EquityIncentivePlanEvergreenProvisionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_A2021EmployeeStockPurchasePlanMember" abstract="true" name="A2021EmployeeStockPurchasePlanMember" 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_A2022InducementEquityPlanEvergreenProvisionMember" abstract="true" name="A2022InducementEquityPlanEvergreenProvisionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ShareBasedPaymentArrangementEvergreenProvisionPercentageOfOutstandingShares" abstract="false" name="ShareBasedPaymentArrangementEvergreenProvisionPercentageOfOutstandingShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types: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-types:domainItemType"/>
  <xs:element id="mnts_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsReleasedInPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsReleasedInPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsReleasedInPeriodWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsReleasedInPeriodWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="mnts_ShareBasedPaymentArrangementOptionsAndUnvestedStockUnitsMember" abstract="true" name="ShareBasedPaymentArrangementOptionsAndUnvestedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_BakerMckenzieMember" abstract="true" name="BakerMckenzieMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_SAFENoteLitigationMember" abstract="true" name="SAFENoteLitigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_FounderLitigationMember" abstract="true" name="FounderLitigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_KhasisClaimMember" abstract="true" name="KhasisClaimMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ANVClaimMember" abstract="true" name="ANVClaimMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_LossContingencyDismissalPeriod" abstract="false" name="LossContingencyDismissalPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_LeaseRestorationCosts" abstract="false" name="LeaseRestorationCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_LeaseRestorationConstructionProposalAmount" abstract="false" name="LeaseRestorationConstructionProposalAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_EffectiveIncomeTaxRateReconciliationLossOnExtinguishmentOfDebtAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationLossOnExtinguishmentOfDebtAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_EffectiveIncomeTaxRateReconciliationLegalContingenciesAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationLegalContingenciesAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_EffectiveIncomeTaxRateReconciliationFinesAndPenaltiesAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationFinesAndPenaltiesAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DeferredTaxAssetsStartUpAndOrganizationalCosts" abstract="false" name="DeferredTaxAssetsStartUpAndOrganizationalCosts" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_DeferredTaxAssetsLeasingArrangements" abstract="false" name="DeferredTaxAssetsLeasingArrangements" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" 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_IssuanceOfPreferredStockAndCommonStockForPrepaidServices" abstract="false" name="IssuanceOfPreferredStockAndCommonStockForPrepaidServices" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_IssuanceOfCommonStockAndPreFundedWarrantsInSettlementOfAccountsPayableAndCustomerDeposits" abstract="false" name="IssuanceOfCommonStockAndPreFundedWarrantsInSettlementOfAccountsPayableAndCustomerDeposits" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_IssuanceCostsRelatedToWarrantModification" abstract="false" name="IssuanceCostsRelatedToWarrantModification" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_IssuanceCostsRelatedToPlacementAgentWarrants" abstract="false" name="IssuanceCostsRelatedToPlacementAgentWarrants" 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_RelativeFairValueOfWarrantsIssuedWithConvertibleNotes" abstract="false" name="RelativeFairValueOfWarrantsIssuedWithConvertibleNotes" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_RelativeFairValueOfWarrantsIssuedWithLoanPayable" abstract="false" name="RelativeFairValueOfWarrantsIssuedWithLoanPayable" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_RemeasurementOfOperatingLeaseRightOfUseAssetsAndLeaseObligations" abstract="false" name="RemeasurementOfOperatingLeaseRightOfUseAssetsAndLeaseObligations" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_January2026ConvertibleNoteMember" abstract="true" name="January2026ConvertibleNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_October2024ConvertibleNoteMember" abstract="true" name="October2024ConvertibleNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_ClassOfWarrantOrRightPeriodUntilSharesBecomeExercisable" abstract="false" name="ClassOfWarrantOrRightPeriodUntilSharesBecomeExercisable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mnts_SaleOfStockRemainingConsiderationAvailable" abstract="false" name="SaleOfStockRemainingConsiderationAvailable" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
