Chandrayaan-1
ThefirstIndian
lunarprobespent
almosta yearinorbit.
ItcontainedtheMoon
MineralogyMapper
imagingspectrometer
instrumentthat
providedthefirsthigh-
resolutionspatialand
spectralmapofthe
entirelunarsurface.NASA'sClementine
Clementinefoundearly
evidenceofwaterice
afterscanningthe
surfacewithradar
in1996.However,
follow-upobservations
withradiotelescopes
suggestedthespots
surveyedhadtoomuch
Sunexposureforice
tosurvive.LunarCrater
Observationand
SensingSatellite
Launchedafterthefirst
detectionofwaterby
Chandrayaan-1,LCROSS
wasenvisionedasa
low-costmeansof
determiningthenature
ofhydrogendetected
atthepolarregionsof
theMoon.LunarProspector
The19-monthmission
wasdesignedfora low-
polarorbitinvestigation
oftheMoon.This
includedmappingthe
surfacecomposition
andlocatinglunar
resources,measuring
magneticandgravity
fieldsandstudying
outgassingevents.maintainingInaisoldhavegivenita facelift.In
2006 PeterH.SchultzatBrownUniversityproposed
a springcleanvialatersubsurfaceoutgassingthat
removedtheoverlyingregolith,whileLeQiao,
visitingBrown,suggesteda recentcollapseintoa
subsurfacevoid.
Wilsonwasinvolvedina 2017paperadvocating
thereplacementofstandardmarebasaltlavawith
a moreexoticvarietythatdegradesdifferently,
creatingtheillusionofyouth.Theirlavaofchoice
isa gas-richmagmaticfoam,likeanextreme
pumice.Whilecriticshavequestionedhowsuch
a fragiledepositcouldsurvivebillionsofyears
ofmicrometeoriteimpacts,Wilsonbelieveshis
solutioncouldlinkIMPstotheoriginofthemare
basaltsthemselves.“MaybeIMPsareplaceswhere
therewerevents?Duringtheverylaststageofthe
mareeruptions,it[thelava]isnotf loodingoutany
more.Thebulkofthegascomesoutinintermittent
explosionsandgas-filledlavas.”
Ontheothersidearethosetryingtokeepthe
Moonvolcanicallyactivelongenoughtoaccount
foreruptionsinthelast 100 millionyears.One
waymightbetoignorethevastmajorityofit.
MostIMPsarelocatedinthesamearea,alongwith
elevatedconcentrationsofthorium,a radioactive
sourceofinternalheatinginsubsurfacerocks.“Alot
ofthepatchesarefoundinareaswherewethink
volcanismcouldhavelastedthelongest.Perhaps
asrecentlyas 50 to 60 millionyearsago,”suggests
Stopar.Andifthelastvestigesoflunarinternal
heathadstuckaroundbeneathcertainpartsofthe
surface,perhapsoccasionalupwellingsmightnot“A lot of the patches
are found in areas
where we think
volcanism could
have lasted the
longest” JulieeStooppar
DescartesHighlands
Modernanalysisofvarious
lunarsamples,includingthose
fromthisApollo 16 site,have
revealedwaterinsideapatite
mineralsofthelavaplainsthat
arisedeepwithintheMoon.Shackleton Crater
Perpetuallyinshadow,the
craterprovidesa coldtrap
tofreezewaterfromcomet
impacts.TheLunarProspector
spacecraftrevealedhigherthan
normalamountsofhydrogen,
indicativeofwaterice.Ta u r u s – L i t t r o wv a l l e y
Aswellaswaterwithin
mineralsfromthelunarinterior,
theApollosamples,likethose
fromApollo17,revealwater
insidecrustalrocks,thought
tobeevidenceofyounger
volcanicintrusions.Rozhdestvenskiy crater
In 2018 a Hawaiian team found
evidence of surface-exposed
water ice within reflectance
spectra of indirect lighting
from the crater’s permanently
shadowed regions.All photos © NASA© ESA
Spacecraft
The Moon is alive