New Frontiers program

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An artists rendering of the spacecraft New Horizons, which launched in 2006 towards Pluto

The New Frontiers program is a series of space exploration missions being conducted by NASA with the purpose of researching several of the Sun's planets including Jupiter, Venus, and the dwarf planet Pluto. NASA is encouraging both domestic and international scientists to submit mission proposals for the project.

New Frontiers was built on the innovative approach used by the Discovery and Explorer Programs of principal investigator-led missions. It is designed for medium-class missions that cannot be accomplished within the cost and time constraints of Discovery, but are not as large as Flagship-class missions. There are currently two New Frontiers missions in progress, New Horizons which launched on January 19, 2006, and Juno which launched on August 5, 2011; a third New Frontiers mission, OSIRIS-REx, has been selected for launch in 2016.

History[edit]

Jupiter and Europa as viewed by New Horizons en route to Pluto

The New Frontiers Program was developed, advocated, and successfully proposed by NASA and the Administration and granted by Congress in CY 2002 and 2003. This effort was led by two long-time NASA executives at Headquarters at that time: Dr. Edward Weiler, Associate Administrator of Science and Dr. Colleen Hartman, Solar System Exploration Division Director. The mission to Pluto had already been selected before this program was successfully endorsed and funded, so the mission to Pluto, called New Horizons, was "grandfathered" into the New Frontiers program. The 2003 Decadal Survey from the National Academy of Sciences identified destinations that then served as the source of the first competition for the New Frontiers Program. The program name was selected by Dr. Hartman based on President John F. Kennedy's speech in 1960, in which he said "We stand, today, on the edge of a New Frontier."

Missions in progress[edit]

New Horizons[edit]

New Horizons, a mission to Pluto, was launched on January 19, 2006, and is on its way to the dwarf planet. After a Jupiter gravity assist in February 2007 the craft has continued towards Pluto. The primary mission flyby will occur in July 2015 and then the spacecraft will be targeted toward one or more additional Kuiper Belt objects between 2015 and 2020.

Juno[edit]

Various features of Juno spacecraft

Juno is a Jupiter exploration mission launched on August 5, 2011. It is the first solar-powered spacecraft to explore an outer planet. The craft will attain a polar orbit in order to study the planet's magnetic field and internal structure. NASA’s Galileo mission to Jupiter provided extensive knowledge about its upper atmosphere, however, further study of Jupiter is crucial not only to the understanding of its origin and nature of the Solar System, but also of giant extrasolar planets in general. The Juno spacecraft investigation is intended to address the following objectives for Jupiter:

  • Understand Jupiter’s gross dynamical and structural properties through determination of the mass and size of Jupiter’s core, its gravitational and magnetic fields, and internal convection;
  • Measure the Jovian atmospheric composition, particularly the condensable-gas abundances (H2O, NH3, CH4 and H2S), the Jovian atmospheric temperature profile, wind velocity profile, and cloud opacity to greater depths than achieved by the Galileo entry probe with a goal of 100 bar at multiple latitudes; and
  • Investigate and characterize the three-dimensional structure of Jupiter’s polar magnetosphere.

OSIRIS-REx (New Frontiers 3)[edit]

OSIRIS-REx Mission Logo December 2013.svg
Planet Earth

On May 25, 2011, NASA selected the OSIRIS-REx mission as its next New Frontiers mission; the name stands for "Origins Spectral Interpretation Resource Identification Security Regolith Explorer".[1] This mission plan is to rendezvous and orbit a special asteroid, at the time named 1999 RQ36 (then 101955 Bennu), by 2020. After extensive measurements, instruments would collect material from the asteroid's surface for return to Earth in 2023. The mission, excluding the launch vehicle, is expected to cost approximately $800 million. The returned samples will help scientists better understand and answer long-held questions about the formation of the Solar System and the origin of complex molecules necessary for life. Also, 101955 is a potential future Earth impactor and is listed on the Sentry Risk Table with the second highest rating on the Palermo Technical Impact Hazard Scale (circa 2011).[2] In the late 2100s there is cumulative chance of about 0.07% it could strike Earth.[3]

Future Missions[edit]

New Frontiers 4[edit]

The next New Frontiers mission will be selected during the decade 2013–2022. Based on their science value and projected costs, the 2013 Planetary Science Decadal Survey committee identified five candidate New Frontiers missions.[4]

Venus In Situ Explorer[edit]

In the 2009 New Frontiers selection, the Venus "Surface and Atmosphere Geochemical Explorer" (SAGE) mission was selected by NASA as a candidate mission study,[5] but was not selected for flight.

The decadal survey lists Venus In-Situ Explorer as a candidate for future New Frontiers selection. This mission would study the composition and surface properties of Venus. The primary science objectives of this mission would be to examine the physics and chemistry of Venus’s atmosphere and crust. The mission should attempt to characterize variables that cannot be measured from orbit, including the detailed composition of the lower atmosphere, and the elemental and mineralogical composition of surface materials.[4]

Although the exploration of the surface and lower atmosphere of Venus provides a major technical challenge, the scientific rewards are major. Venus is Earth’s sister planet, yet its tectonics, volcanism, surface-atmospheric processes, atmospheric dynamics and chemistry are all remarkably different from those on Earth, which has resulted in remarkably different end states for its surface crust and atmosphere. While returning physical samples of its surface and/or atmosphere may not be possible within the New Frontiers cost cap, innovative approaches might achieve the majority of the following objectives:

  • Understand the physics and chemistry of Venus’ atmosphere through measurement of its composition, especially the abundances of its trace gases, light stable isotopes, and noble gas isotopes;
  • Understand the physics and chemistry of Venus’ crust through analysis of near-IR descent images from below the clouds to the surface and through measurements of elemental abundances and mineralogy from a surface sample;
  • Understand the properties of Venus’ atmosphere down to the surface through meteorological measurements and improve our understanding of Venus’ zonal cloud-level winds through temporal measurements over at least two Earth days; and
  • Understand the weathering environment of the crust of Venus in the context of the dynamics of the atmosphere of Venus and the composition and texture of its surface materials.

Lunar South Pole-Aitken Basin Sample Return[edit]

Aitken crater as seen by Apollo

The Lunar South Pole-Aitken Basin Sample Return would return samples of the early Moon's deep crust. Had Moonrise been selected as the 3rd New Frontiers mission, Lunar South Pole-Aitken Basin Sample Return would have been removed from consideration.

The surface of the South Pole-Aitken basin, located on the Moon’s far side southern polar region, is likely to contain some fraction of the mineralogy of the Moon’s lower crust. Samples of these ancient materials that are not biased by nearside impact basin formation are highly desirable to further understand the history of Earth’s Moon. Therefore, a mission to return a sufficient sample of material from the heretofore-unsampled South Pole-Aitken basin terrain, including useful samples from the deep crust of the early Moon, should accomplish (following chemical, isotopic, and petrologic analysis of returned materials as well as radiometric age dating on Earth) the majority of following science objectives:

Possible configuration of the spacecraft
  • Elucidate the nature of the Moon’s lower crust and mantle by direct measurements of its composition and of sample ages;
  • Determine the chronology of basin-forming impacts and constrain the period of late, heavy bombardment in the inner Solar System, and thus, address fundamental questions of inner Solar System impact processes and chronology;
  • Characterize a large lunar impact basin through "ground truth" validation of global, regional, and local remotely sensed data of the sampled site;
  • Elucidate the sources of thorium and other heat-producing elements in order to understand lunar differentiation and thermal evolution; and
  • Determine ages and compositions of far-side basalts to determine how mantle source regions on the far side of the Moon differ from regions sampled by Apollo and Luna basalts.[6]

Trojan Tour and Rendezvous[edit]

The Trojan Tour and Rendezvous mission would fly by two or more Jupiter Trojans, asteroids that orbit around the L4 and L5 Lagrange points at the same distance from the Sun as Jupiter, and then settle into orbit around one of them - similar goals to the Dawn mission, though significantly further from the Sun.

Comet Surface Sample Return[edit]

A Comet Surface Sample Return mission would acquire and return to Earth a macroscopic sample from the surface of a comet nucleus using a sampling technique that preserves organic material in the sample.

Detailed study of comets promises the possibility of understanding the physical condition and constituents of the very early Solar System, including the early history of water and the biogenic elements and the compounds containing them. Therefore, a mission that would sample and return the dust and organics from at least one if not several locations on the surface of a comet nucleus, including one in the vicinity of an active vent, is of prime interest in order to achieve the majority of the following science objectives:

  • Understand the structure and composition of a comet through measurement of the chemical complexity of the sampled material, grain micro texture and its cohesive forces, age and composition of ices and organic and silicate grains;
  • Understand the real time dynamics and evolution of a comet’s surface under the influence of sunlight by study of the diurnal conditions of its atmosphere and surface; and
  • Investigate a comet’s overall physical structure in order to assess its internal heterogeneity.

Saturn Probe[edit]

Saturn view by the Cassini orbiter

A Saturn Probe mission would deploy a probe into Saturn’s atmosphere to determine the structure of the atmosphere as well as noble gas abundances and isotopic ratios of hydrogen, carbon, nitrogen, and oxygen. A carrier/relay craft with the probe would arrive at Saturn approximately seven years after launch. Thirty days or more before arrival, the probe separates from the carrier/relay craft. The probe would enter the atmosphere and begin measurements at 0.1 bars (a bar is the atmospheric pressure at sea level on Earth). At 1 bar, the probe would detach from its parachute for a more rapid descent to 5 bars and the end of the nominal mission after 55 minutes of data collection. The probe would be designed to survive to 10 bars, and the carrier/relay would continue to listen for as long as the entry site remains visible.[7]

New Frontiers 5[edit]

In addition to the five mission concepts listed above, for the 5th New Frontiers mission, the 2013 Planetary Science Decadal Survey committee identified two additional candidates that will be added to the list.[4]

Io Observer[edit]

The focus of this mission is to determine the internal structure of Io and to investigate the mechanisms that contribute to the satellite's intense volcanic activity from a highly elliptical orbit around Jupiter, making multiple flybys of Io. This mission depends on sufficient advances in system power and radiation protection.[7]

Lunar Geophysical Network[edit]

This mission consists of several identical landers distributed across the lunar surface, each carrying geophysical instrumentation. The primary science objectives are to characterize the Moon’s internal structure, seismic activity, global heat flow budget, bulk composition, and magnetic field. It would expand the instruments left on the surface on the moon left by Apollo program missions to include coverage the far side of the moon as well.[7]

References[edit]

  1. ^ NASA. "NASA to Launch New Science Mission to Asteroid in 2016". Retrieved 25 May 2011. 
  2. ^ "Sentry Risk Table". NASA/JPL Near-Earth Object Program Office. 14 Oct 2011. Archived from the original on 21 July 2011. Retrieved 2011-10-14. 
  3. ^ Milani, Andrea; Chesley, Steven R.; Sansaturio, Maria Eugenia; Bernardi, Fabrizio; Valsecchi, Giovanni B.; Arratia, Oscar (2009). "Long term impact risk for (101955) 1999 RQ36". Icarus 203 (2): 460–471. arXiv:0901.3631. Bibcode:2009Icar..203..460M. doi:10.1016/j.icarus.2009.05.029. 
  4. ^ a b c Vision and Voyages for Planetary Science in the Decade 2013-2022. Washington, DC: National Academies. 2011. pp. ES–1. ISBN 978-0-309-20951-9. 
  5. ^ "New Frontiers missions 2009". NASA. Retrieved 2011-12-09. 
  6. ^ "SAMPLING THE SOUTH POLE-AITKEN BASIN: OBJECTIVES AND SITE SELECTION CRITERIA". Lunar Planetary Institute. 
  7. ^ a b c Squyres, Steve. "Vision and Voyages For Planetary Science in the Decade 2013-2022". National Research Council. 

External links[edit]