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  <xs:element id="mnts_AuditInformationAbstract" abstract="true" name="AuditInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <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_PurchasesOfIntangiblesAssetsDuringNoncashOrPartialNoncashTransactionIncludedInAccountsPayableAndAccruedExpenses" abstract="false" name="PurchasesOfIntangiblesAssetsDuringNoncashOrPartialNoncashTransactionIncludedInAccountsPayableAndAccruedExpenses" nillable="true" xbrli:periodType="duration" 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_TermLoanMember" abstract="true" name="TermLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_HostedPayloadServicesMember" abstract="true" name="HostedPayloadServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_DOrbitSpAMember" abstract="true" name="DOrbitSpAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_IssuanceOfCommonStockForConsultingServices" abstract="false" name="IssuanceOfCommonStockForConsultingServices" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ScheduleOfReverseRecapitalizationTable" abstract="true" name="ScheduleOfReverseRecapitalizationTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <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_ShareRepurchaseLiabilityCurrent" abstract="false" name="ShareRepurchaseLiabilityCurrent" nillable="true" xbrli:periodType="instant" 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_ClassOfWarrantOrRightConsiderationPerShare" abstract="false" name="ClassOfWarrantOrRightConsiderationPerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="mnts_FebruaryClassAWarrantsMember" abstract="true" name="FebruaryClassAWarrantsMember" 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_CommonAndPreferredStockSharesAuthorized" abstract="false" name="CommonAndPreferredStockSharesAuthorized" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_ScheduleOfReverseRecapitalizationLineItems" abstract="true" name="ScheduleOfReverseRecapitalizationLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <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_ReverseRecapitalizationConsiderationTypeAxis" abstract="true" name="ReverseRecapitalizationConsiderationTypeAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="mnts_StockIssuedDuringPeriodSharesPurchaseOfPreFundedWarrants" abstract="false" name="StockIssuedDuringPeriodSharesPurchaseOfPreFundedWarrants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="mnts_ShareBasedPaymentArrangementNumberOfSharesModified" abstract="false" name="ShareBasedPaymentArrangementNumberOfSharesModified" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <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_PrepaidResearchAndDevelopmentExpenseCurrent" abstract="false" name="PrepaidResearchAndDevelopmentExpenseCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_MarchWarrantsMember" abstract="true" name="MarchWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_PrepaidLaunchCostsImpairmentCharges" abstract="false" name="PrepaidLaunchCostsImpairmentCharges" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_SaleOfStockPaymentOfLiability" abstract="false" name="SaleOfStockPaymentOfLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_ConsiderationFromFundsLegallyAvailableMember" abstract="true" name="ConsiderationFromFundsLegallyAvailableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="mnts_NumberOfThirdPartyCustomerSatellitesDeployedInLowEarthOrbit" abstract="false" name="NumberOfThirdPartyCustomerSatellitesDeployedInLowEarthOrbit" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <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_PaymentOfDeferredOfferingCosts" abstract="false" name="PaymentOfDeferredOfferingCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_TransportationServicesMember" abstract="true" name="TransportationServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_LesseeOperatingLeaseNumberOfLeasesModified" abstract="false" name="LesseeOperatingLeaseNumberOfLeasesModified" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_WarrantOfferingFeesAndOtherExpensesPayable" abstract="false" name="WarrantOfferingFeesAndOtherExpensesPayable" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_A2021EmployeeStockPurchasePlanMember" abstract="true" name="A2021EmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
</xs:schema>
