Editing Discovery Program (section)

=== Discovery 3 and 4 ===
[[File:Lunar Thorium concentrations.jpg|thumb|Thorium concentrations on the Moon, as mapped by ''Lunar Prospector'']]
In August 1994, NASA made an Announcement of Opportunity for the next proposed Discovery missions.<ref name=d95>{{cite web|url=http://nssdc.gsfc.nasa.gov/planetary/discover95.txt |title=Discover 95: Mission to the Moon, Sun, Venus and a Comet Picked for Discovery – NASA |access-date=2018-04-28}}</ref> There were 28 proposals submitted to NASA in October 1994:<ref name=d95/> 
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# ASTER - Asteroid Earth Return
# Comet Nucleus Penetrator
# Comet Nucleus Tour (CONTOUR)
# Cometary Coma Chemical Composition (C4)
# Diana  (Lunar and Cometary Mission)
# FRESIP-A mission to Find the Frequency of Earth-sized Inner Planets
# Hermes Global Orbiter (Mercury Orbiter)
# Icy Moon Mission (Lunar Orbiter)
# Interlune-One (Lunar Rovers)<ref>{{cite web |url=https://www.researchgate.net/publication/234389634 |title=Interlune-One: A Scientific Mission Across the Surface of the Moon (PDF Download Available) |website=Researchgate.net |access-date=January 11, 2016}}</ref>
# Jovian Integrated Synoptic Telescope (IO Torus investigation)
# Lunar Discovery Orbiter<ref>{{cite web |url=https://tucsoncitizen.com/morgue2/1995/01/27/97568-ua-scientist-seeking-big-bucks-from-nasa/ |title=UA scientist seeking big bucks from NASA – Tucson Citizen Morgue, Part 2 (1993–2009) |website=Tucsoncitizen.com |date=January 27, 1995 |access-date=January 11, 2016}}</ref>
#  {{Background color|#EEE|'''[[Lunar Prospector]]''' (Lunar Orbiter) – chosen in February 1995 for Discovery 3.}}
# Mainbelt Asteroid Exploration/Rendezvous
# Mars Aerial Platform (Atmospheric)
# Mars Polar Pathfinder (Polar Lander)
# Mars Upper Atmosphere Dynamics, Energetics and Evolution
# Mercury Polar Flyby
# Near Earth Asteroid Returned Sample
# Origin of Asteroids, Comets and Life on Earth
# PELE: A Lunar Mission to Study Planetary Volcanism
# Planetary Research Telescope
# Rendezvous with a Comet Nucleus (RECON)
#  {{Background color|#EEE|'''Suess-Urey''' (Solar Wind Sample Return) – Discovery 4 finalist.}}
# Small Missions to Asteroids and Comets
#  {{Background color|#EEE|'''[[Stardust (spacecraft)|Stardust]]''' (Cometary/Interstellar Dust Return) – Discovery 4 finalist.}}
# Venus Composition Probe (Atmospheric)
# Venus Environmental Satellite (Atmospheric)
#  {{Background color|#EEE|'''Venus Multi-Probe Mission''' (Atmospheric)<ref>{{cite web |url=https://ntrs.nasa.gov/search.jsp?R=20020038535 |title=NASA Technical Reports Server (NTRS) – Venus Multiprobe Mission |website=Ntrs.nasa.gov |date=January 2001 |access-date=January 11, 2016}}</ref> – Discovery 4 finalist.}}
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In February 1995, ''[[Lunar Prospector]]'', a lunar orbiter mission, was selected for launch. Three other missions were left to undergo a further selection later in 1995 for the fourth Discovery mission: ''Stardust'', ''Suess-Urey'', and ''Venus Multiprobe''.<ref name=d95/> [[Stardust (spacecraft)|''Stardust'']], a comet sample-return mission, was selected in November 1995 over the two other finalists.<ref name="autogenerated1">{{cite web |url=http://stardust.jpl.nasa.gov/news/sd-selected.html |title=STARDUST Selected as Discovery Flight |website=Stardust.jpl.nasa.gov |access-date=January 11, 2016}}</ref>