{"id":16110,"date":"2015-08-25T23:23:15","date_gmt":"2015-08-25T15:23:15","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/uranus-neptune-in-nasas-sights-for-new-robotic-mission\/"},"modified":"2015-08-25T23:23:15","modified_gmt":"2015-08-25T15:23:15","slug":"uranus-neptune-in-nasas-sights-for-new-robotic-mission","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/uranus-neptune-in-nasas-sights-for-new-robotic-mission\/","title":{"rendered":"Uranus, Neptune in NASA\u2019s sights for new robotic mission"},"content":{"rendered":"
\"NASA's
NASA\u2019s Voyager 2 mission captured this image of Uranus during its January 1986 flyby, the only encounter with the distant ice giant. Credit: NASA<\/figcaption><\/figure>\n

NASA has asked scientists to assess how to design and fly robotic space probes to Uranus and Neptune, the last of the solar system\u2019s classical planets yet to be orbited, likely ensuring the huge icy worlds are near the top of the space agency\u2019s to-do list in the coming decades.<\/p>\n

Led the Jet Propulsion Laboratory, the study will look at ideas for orbiters that could be dispatched Uranus and Neptune in the late 2020s or early 2030s and study the giant planet\u2019s structures, composition and extensive moon systems.<\/p>\n

One focus of the study will be designing a common spacecraft platform that could be developed in two copies and launched to Uranus and Neptune for about $2 billion each, according to Jim Green, head of NASA\u2019s planetary science division.<\/p>\n

But Green said scientists should look at scaled-back concepts that could be developed at less cost.<\/p>\n

\u201cWe want to identify potential concepts across a spectrum of price points,\u201d Green said Monday in a meeting of a NASA-sponsored science working group devoted to outer planets research. \u201cOne of our (impediments) to make missions happen is the huge price tag it takes in order to be able to get out to the outer solar system.\u201d<\/p>\n

The study is the first bureaucratic step in a multi-year effort involving independent cost and technical assessments, scientific peer review and federal budgeting before a mission to one of the icy giant planets goes from the drawing board to reality, Green said.<\/p>\n

Results from the study will be presented to a panel of scientists seated by the National Research Council in the early 2020s. The NRC committee meets once per decade to map out the top priorities for the next 10 years of planetary science research, producing a report that ranks mission concepts for consideration by NASA decision-makers.<\/p>\n

The space agency\u2019s policy is to follow the decadal survey\u2019s recommendations.<\/p>\n

A mission to Uranus or Neptune will likely be a multibillion-dollar flagship-class mission in the mold of NASA\u2019s Cassini orbiter flying around Saturn and a recently-approved probe to repeatedly fly by Jupiter\u2019s icy moon Europa.<\/p>\n

\"NASA's
NASA\u2019s Voyager 2 spacecraft encountered Neptune in August 1989. Credit: NASA<\/figcaption><\/figure>\n

NASA\u2019s budget for planetary science can only support development of one such costly mission at a time, so only low-level work on a follow-up flagship project is affordable until after the Europa mission departs Earth in 2022.<\/p>\n

\u201cObviously, it\u2019s not going to be easy to be able, even after we get Europa under our belt, to actually execute on the next large mission, but we need to make progress to understand our science priorities and look at this in a way that will prepare us for the next decade, but also utilize new technologies and capabilities that have come up (since the last decadal survey),\u201d Green said Monday.<\/p>\n

The last decadal survey report issued in 2011 set NASA\u2019s foremost planetary science objectives as a Mars sample return mission and a probe to Europa.<\/p>\n

NASA\u2019s next Mars rover set for launch in 2020 will collect and store rock specimens for retrieval and return to Earth by a future mission, fulfilling the first step in a multi-mission odyssey to bring back samples from the red planet\u2019s surface. And NASA formally approved the Europa flyby probe earlier this year to assess the icy moon\u2019s habitability.<\/p>\n

A Uranus orbiter was third in line in the 2011 decadal survey, but NASA\u2019s budget will keep the mission grounded until at least the late 2020s. That means NASA\u2019s ultimate approval of the mission depends on it faring well in the next decadal assessment by the National Research Council.<\/p>\n

It is likely to be up against strong backing for a robotic mission dedicated to Saturn\u2019s moon Titan, which has seas and rivers of liquid hydrocarbons like methane, and another flagship mission to Mars to pick up the samples collected by the 2020 rover.<\/p>\n

A lander or rover mission to Venus may also gain support in the next decadal report. The surface of the sweltering cloud-shrouded world has not been explored since Soviet-era lander missions in the 1980s.<\/p>\n

NASA is expected to request similar conceptual studies on other leading contenders for future flagship missions heading into the next decadal survey, but Uranus and Neptune are first in the lot.<\/p>\n

\"A
A concept for a Uranus orbiter and atmospheric entry probe was evaluated during the last decadal survey report released in 2011. Credit: NASA\/NRC Decadal Survey<\/figcaption><\/figure>\n

Orbiters for Uranus and Neptune will almost certainly rely on nuclear batteries powered by plutonium, and U.S. government funding of additional production of space-grade plutonium ensures such projects will have the power resources they need, Green said.<\/p>\n

Engineers pack pellets of plutonium-238, the isotope tailored for electricity in space, into radioisotope generators. The natural decay of plutonium-238 produces heat, which is transferred through thermoelectric couples to generate electricity.<\/p>\n

\u201cIt would be after 2023, as we get into the next decade that we would consider using radioisotope power for those missions, if they survive the decadal process, which I\u2019m sure they will,\u201d Green said Monday.<\/p>\n

Nuclear power is required for probes in the far reaches of the solar system, where sunlight is insufficient for solar arrays. NASA\u2019s New Horizons mission to Pluto, the Cassini mission at Saturn and the Curiosity rover on Mars currently rely on plutonium power sources.<\/p>\n

Uranus orbits about 1.8 billion miles from the sun, more than three times farther than Jupiter, and Neptune is positioned 2.8 billion miles away.<\/p>\n

Other objectives of the JPL study include assessing how Uranus and Neptune research probes could benefit from advanced sensor technologies, such as compact instrumentation and high-resolution cameras. Green said the study will also examine how NASA\u2019s powerful Space Launch System, which is being considered for the launch of the Europa mission in 2022, could allow for bigger, more capable and less risky missions to Uranus and Neptune that could make the trip in a fraction of the time feasible if the probes used a smaller rocket.<\/p>\n

\u201cThere is this underground sentiment that we do need to get back to the outer solar system, but it\u2019s just so hard,\u201d said Heidi Hammel, a planetary astronomer who is executive vice president of the Association of Universities for Research in Astronomy. \u201cWe\u2019re working on technology to make it not so hard and so expensive.\u201d<\/p>\n

\"Neptune
Neptune and its largest moon Triton are pictured in this view from NASA\u2019s Voyager 2 mission in 1989. Credit: NASA<\/figcaption><\/figure>\n

NASA also tasked JPL to identify ways international partners could participate in the missions and to establish a science definition team for Uranus and Neptune.<\/p>\n

Some scientists view Uranus and Neptune as the logical next step in the strategic exploration of the solar system, and orbiters to one or both of the huge planets could arrive about a half-century after their first encounters by NASA\u2019s Voyager 2 probe.<\/p>\n

\u201cThe planetary decadal puts a Uranus mission very high,\u201d Green told reporters in July in a briefing during the New Horizons flyby of Pluto. \u201cEven though those are giant planets \u2014 Uranus and Neptune \u2014 they have a lot of major compositional differences from the big gas giants \u2014 that are primarily hydrogen and helium \u2014 which is Saturn and Jupiter. We call those \u2014 Uranus and Neptune \u2014 ice giants because they have a lot of ammonia and other material.\u201d<\/p>\n

Scientists believe Uranus and Neptune are composed mostly of rock and ice, with a dense, layered atmosphere. Researchers are not sure where they got so much ice, but some experts believe Uranus and Neptune were bombarded with frozen primordial objects from the Kuiper Belt, a ring of frigid proto-worlds beyond Neptune that contains Pluto and dozens more nation-sized dwarf planets.<\/p>\n

Surprising discoveries by the New Horizons flyby of Pluto, revealing the diminutive icy world to show signs of apparent glacial flows and ongoing geologic activity, have renewed attention on the mostly unexplored far edges of the solar system, such as the Kuiper Belt.<\/p>\n

\u201cOur new frontier is the outer part of the solar system,\u201d Green said.<\/p>\n

At least some of the outer giant planets\u2019 moons, such as Neptune\u2019s Triton, are likely intact remnants from the ancient Kuiper Belt that were captured billions of years ago.<\/p>\n

\u201cIf we want to go back to a Kuiper Belt Object (after New Horizons), we may not have to go into the Kuiper Belt to get it,\u201d Green said in July. \u201cWe may want to go to Neptune to visit Triton, which is closer. Although Neptune is a heck of a distance away, it\u2019s still not as far as some of the Kuiper Belt Objects.\u201d<\/p>\n

\"NASA
NASA created this size comparison chart for the solar system\u2019s giant outer planets based in imagery from the Voyager missions. Credit: NASA\/JPL-Caltech<\/figcaption><\/figure>\n

\u201cI think the science case for a future mission to one \u2014 or both \u2014 of the ice giants is strong, and I do expect them to be well placed in the next decadal survey,\u201d said Mark Hofstadter, a planetary scientist who led studies for a Uranus mission in the late 2000s.<\/p>\n

\u201cThe announcement yesterday from Jim Green means that the next decadal will be better positioned to identify a realistic and capable mission, and its cost,\u201d Hofstadter told Spaceflight Now.<\/p>\n

For William McKinnon, a planetary geologist at Washington University in St. Louis, another visit to Uranus or Neptune would be fascinating, he tells Spaceflight Now.<\/p>\n

But McKinnon, who currently analyzes fresh data on Pluto from New Horizons, brings up an often-overlooked concern among scientists working on probes to faraway destinations: It takes decades to design, build and fly such a mission, followed by more years of data crunching.<\/p>\n

\u201cAn ice giant mission, presumably an orbiter, is, alas, over the horizon as far as my lifespan is concerned, so I salute those who will live to see it!\u201d<\/p>\n

Email the author.<\/i><\/b><\/p>\n

Follow Stephen Clark on Twitter: @StephenClark1.<\/strong><\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

NASA\u2019s Voyager 2 mission captured this image of Uranus during its January 1986 flyby, the only encounter with the distant ice giant. Credit: NASA NASA has asked scientists to assess how to design and fly robotic space probes to Uranus and Neptune, the last of the solar system\u2019s classical planets yet to be orbited, likely […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[2076,2336,1561,3829,3977],"class_list":["post-16110","post","type-post","status-publish","format-standard","hentry","category-news","tag-decadal-survey","tag-neptune","tag-planetary-science","tag-plutonium","tag-uranus"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/16110"}],"collection":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/comments?post=16110"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/16110\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=16110"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=16110"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=16110"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}