Editing Discovery Program (section)

===Venus focused===
* '''Venus Multiprobe''', proposed for a 1999 launch, would have dropped 16 atmospheric probes into Venus, which would fall slowly to the surface, taking pressure and temperature measurements.<ref name="nasa" />
* '''Vesper''', a concept for a Venus orbiter focused on studying the planet's atmosphere.<ref name="finalists">{{cite web |url=http://deepimpact.umd.edu/press/98-203.html |series=Press Releases |title=Deep Impact: Five Discovery Mission Proposals Selected for Feasibility Studies |work=Deep Impact |publisher=University of Maryland |date=November 12, 1998 |archive-url=https://web.archive.org/web/20020620083019/http://deepimpact.umd.edu/press/98-203.html |archive-date=June 20, 2002 |url-status=live}}</ref><ref name="vesper">{{cite web |url=http://www.nasa.gov/centers/goddard/news/topstory/2006/vesper.html |title=NASA – Vesper Could Explore Earth's Fiery Twin |publisher=NASA |archive-url=https://web.archive.org/web/20070823131906/http://www.nasa.gov/centers/goddard/news/topstory/2006/vesper.html |archive-date=August 23, 2007 |url-status=live}}</ref><ref>{{cite journal |title=The VESPER Mission to Venus |volume = 30|pages = 1106|journal=Astrophysics Data System |publisher=Harvard-Smithsonian Centre for Astrophysics |bibcode = 1998BAAS...30.1106A|last1 = Allen|first1 = M.|last2 = Chin|first2 = G.|author3 = VESPER Science Team|year = 1998}}</ref> It was one of three concepts to receive funds for further study in the 2006 Discovery selection.<ref name="vesper" /> Osiris and GRAIL were the other two, and eventually GRAIL was chosen and went on to be launched.<ref name="select" /> 
* '''V-STAR''' (Venus Sample Targeting, Attainment and Return), a Venus sample return mission with a goal of understanding Venus's evolution.<ref name="vsr">{{cite web |url=http://henry.pha.jhu.edu/2007_Academy_Group_Project.pdf |title=Venus Sample Targeting, Attainment, and Return (V-STAR) |work=2007 NASA Academy at the Goddard Space Flight Center |publisher=The Henry Foundation |archive-url=https://web.archive.org/web/20120315021449/http://henry.pha.jhu.edu/2007_Academy_Group_Project.pdf |archive-date=March 15, 2012 |url-status=dead  }}</ref><ref name="trs_0542">{{cite web |url=http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/14139/1/00-0542.pdf |title=Venus Sample Return Missions – A Range of Science, A Range of Costs |first1=Ted |last1=Sweetser |first2=Craig |last2=Peterson |first3=Erik |last3=Nilsen |first4=Bob |last4=Gershman |publisher=California Institute of Technology |archive-url=https://web.archive.org/web/20100526220032/http://trs-new.jpl.nasa.gov/dspace/bitstream/2014/14139/1/00-0542.pdf |archive-date=May 26, 2010 |url-status=dead  }}</ref> The mission would have consisted of a [[Venus]] orbiter with an attached lander. The lander would fall through the Venusian atmosphere, collecting samples along the way, as well as after landing through the use of a "mole". Said lander would launch those samples into a low orbit, where they would rendezvous with the orbiter, returning the samples to Earth.<ref name="vsr" />
* '''VEVA''' (Venus Exploration of Volcanoes and Atmosphere), an atmospheric probe for Venus.<ref name="veva">{{cite journal  |title=VEVA Discovery mission to Venus: exploration of volcanoes and atmosphere |first1=Kenneth |last1=Klaasen |first2=Ronald |last2=Greeley |date=March 31, 2003| doi=10.1016/s0094-5765(02)00151-0 |volume=52 |issue=2–6 |journal=Acta Astronautica |pages=151–158|bibcode=2003AcAau..52..151K }}</ref> The main component is a 7-day balloon flight through the atmosphere accompanied by various small probes dropped deeper into the planet's thick gases.<ref name="veva" />
* '''Venus Pathfinder''', a long-duration Venus lander.<ref>{{cite web |url=http://www.planetaryprobe.org/sessionfiles/session2/papers/lorenz_venus_lander-paper.pdf |title=Venus Pathfinder: A Stand-Alone Long-Lived Venus Lander Mission Concept |first1=Ralph D. |last1=Lorenz |first2=Doug |last2=Mehoke |first3=Stuart |last3=Hill |work=8th International Planetary Probe Workshop (IPPW-8) |publisher=National Institute of Aerospace |archive-url=https://web.archive.org/web/20140227204705/http://www.planetaryprobe.org/sessionfiles/session2/papers/lorenz_venus_lander-paper.pdf |archive-date=February 27, 2014 |url-status=dead  }}</ref> 
* '''RAVEN''', a Venus orbiter radar mapping mission.<ref>{{cite journal |bibcode=2009AGUFM.P31D..04S |title=RAVEN – High-resolution Mapping of Venus within a Discovery Mission Budget |last1=Sharpton |first1=V. L. |last2=Herrick |first2=R. R. |last3=Rogers |first3=F. |last4=Waterman |first4=S. |journal=Astrophysics Data System |volume=2009 |pages=P31D–04 |publisher=Harvard-Smithsonian Centre for Astrophysics |year=2009 }}</ref>
* '''VALOR''', a Venus mission to study its atmosphere with a balloon.<ref name="val">{{cite web |url=https://smartech.gatech.edu/bitstream/handle/1853/26401/65-172-1-PB.pdf |title=Exploring Venus with Balloons: Science Objectives and Mission Architectures for small and Medium-Class Missions |first1=Kevin H. |last1=Baines |first2=Jeffery L. |last2=Hall |first3=Tibor |last3=Balint |first4=Viktor |last4=Kerzhanovich |first5=Gary |last5=Hunter |first6=Sushil K. |last6=Atreya |first7=Sanjay S. |last7=Limaye |first8=Kevin |last8=Zahnle |publisher=Georgia Tech Library |archive-url=https://web.archive.org/web/20140227192352/https://smartech.gatech.edu/bitstream/handle/1853/26401/65-172-1-PB.pdf |archive-date=February 27, 2014 |url-status=live}}</ref> Twin balloons would circumnavigate the planet over 8 Earth-days.<ref name="val" /> 
* '''Venus Aircraft''', a robotic atmospheric flight on Venus's atmosphere using a long-duration solar-powered aircraft system.<ref name="VenusAirplane">{{cite conference |conference=40th AIAA Aerospace Sciences Meeting & Exhibit |citeseerx=10.1.1.195.172 |title=NASA TM-2002-0819 : Atmospheric Flight on Venus |first1=Geoffrey A. |last1=Landis |first2=Christopher |last2=LaMarre |first3=Anthony |last3=Colozza |publisher=American Institute of Aeronautics and Astronautics, The Pennsylvania State University |date=January 14, 2002 |doi=10.2514/6.2002-819 }}</ref> It would carry 1.5&nbsp;kg of scientific payload and would contend with violent wind, heat and a corrosive atmosphere.<ref name="VenusAirplane" />
* [[Venus Landsailing Rover|Zephyr]], a rover concept that would be propelled by the wind force on its vertical wingsail. Conceived in 2012, the project has since made progress in developing electronic components that would allow the vehicle to operate for 50 days on the surface of Venus without a cooling system.<ref name='Zephyr 2015 Report'>[https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150000879.pdf Zephyr: A Landsailing Rover For Venus]. (PDF) Geoffrey A. Landis, Steven R. Oleson, David Grantier, and the COMPASS team. NASA John Glenn Research Center. 65th International Astronautical Congress, Toronto, Canada. February 24, 2015.  Report: IAC-14,A3,P,31x26111</ref>