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  <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_SecondLienPromissoryNotesNoteTwoMember" abstract="true" name="SecondLienPromissoryNotesNoteTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_RestrictedStockUnitsAndRestrictedStockAwardsMember" abstract="true" name="RestrictedStockUnitsAndRestrictedStockAwardsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_DeferredFulfillmentAndPrepaidLaunchCostsRecoveries" abstract="false" name="DeferredFulfillmentAndPrepaidLaunchCostsRecoveries" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_SECInvestigationMember" abstract="true" name="SECInvestigationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_LossContingencyDamagesSoughtPerBreachValue" abstract="false" name="LossContingencyDamagesSoughtPerBreachValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" 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_ReverseRecapitalizationProceedsReceivedInCashFromOperations" abstract="false" name="ReverseRecapitalizationProceedsReceivedInCashFromOperations" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_ReverseRecapitalizationContingentConsiderationEquityNonTransferPeriodStockPriceTrigger" abstract="false" name="ReverseRecapitalizationContingentConsiderationEquityNonTransferPeriodStockPriceTrigger" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <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_CloudComputingImplementationIntangiblesMember" abstract="true" name="CloudComputingImplementationIntangiblesMember" 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_ReverseRecapitalizationConsiderationTypeDomain" abstract="true" name="ReverseRecapitalizationConsiderationTypeDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_CommonStockSharesOutstandingByShareholdersDomain" abstract="true" name="CommonStockSharesOutstandingByShareholdersDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_FairValueAdjustmentOfFinancialInstrumentsSubjectToMandatoryRedemption" abstract="false" name="FairValueAdjustmentOfFinancialInstrumentsSubjectToMandatoryRedemption" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_WeightedAverageClosingPriceAxis" abstract="true" name="WeightedAverageClosingPriceAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <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_ShareBasedPaymentArrangementOptionsAndUnvestedStockUnitsMember" abstract="true" name="ShareBasedPaymentArrangementOptionsAndUnvestedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mnts_RecapitalizationExchangeRatio" abstract="false" name="RecapitalizationExchangeRatio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="mnts_ContractWithCustomerLiabilityRevenueRecognizedForCancelledContracts" abstract="false" name="ContractWithCustomerLiabilityRevenueRecognizedForCancelledContracts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_NumberOfLaunchAgreementsTerminated" abstract="false" name="NumberOfLaunchAgreementsTerminated" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="mnts_WarrantsFairValueAdjustment" abstract="false" name="WarrantsFairValueAdjustment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mnts_May222021StockOptionModificationsMember" abstract="true" name="May222021StockOptionModificationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
