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Curiosity landing illustration
Despite the concerns about the future of NASA’s planetary science program, we are in a “golden age” of planetary exploration, with Curiosity’s landing on Mars a prime example. (credit: entroz at deviantART)

History’s rhymes


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“In the midst of events, there is no perspective.” — Barbara Tuchman

“History does not repeat itself, but it does rhyme.” — Mark Twain

“History is just one damned thing after another.” — Arnold J. Toynbee

Is history—human events—just never-ending repetition, or does it progress, with humanity learning and avoiding the mistakes of the past?

In late October NASA celebrated the fiftieth anniversary of Mariner 2’s arrival at Venus with a history symposium held in Crystal City, a picturesque suburb of Washington located near National Airport. The symposium was recently covered by Jeff Foust (see “Planetary science turns to history to help guide its future”, The Space Review, November 19, 2012). Although Foust focused upon a few presentations, the presenters covered a wide range of planetary science history subjects. Two dozen speakers spoke about subjects such as the Voyager missions, asteroid impacts depicted in the movies and television, the creation of the Discovery program of relatively small spacecraft, Soviet planetary science achievements, the “faster cheaper better” program of the 1990s, the politics of planetary mission selection, and the origins of the Skycrane landing system for the Curiosity rover.

That impression of gloom and doom needs to be tempered a bit with a little broader perspective. For starters, we are currently in the Golden Age of Planetary exploration.

Despite the breadth of topics, the unintentional theme of the symposium became what past events can tell us about the current state of NASA’s planetary science program. This unfortunate theme was not really the result of talks about the early 1980s period when it looked like NASA planetary exploration was “going out of business,” or the late 1990s failure of two Mars missions and the reorganization of the Mars exploration program. Rather, it had more to do with the fact that there were question sessions after each presentation, and a few of the questioners repeatedly focused on the current budget issues facing NASA’s planetary science program, even if the topic of the presentation had little relevance to that subject. Thus, while the symposium covered a half century of stunning accomplishment, the atmosphere at times seemed as gloomy as the pre-Hurricane Sandy skies outside the conference room.

That impression of gloom and doom needs to be tempered a bit with a little broader perspective. For starters, we are currently in the Golden Age of Planetary exploration. People tend to be sentimental, and so it is easy to pine for the days of Viking and Voyager, when everything was a “first,” the solar system seemed so new, and discoveries tasted so fresh. But measured in terms of knowledge, we are right now experiencing the greatest-ever expansion of our understanding of our whirling collection of rocks, dust, and gas in this small, unfashionable corner of the Milky Way. Right now there are more spacecraft operating, around more planets, gathering more data, than ever before. A simple box score of currently operating spacecraft demonstrates the case:

Mercury
MESSENGER

Venus
Venus Express

The Moon
Lunar Reconnaissance Orbiter
GRAIL (mission ended a few days ago)
Artemis (two fields and particles spacecraft)

Mars
Mars Express
Mars Odyssey
Mars Reconnaissance Orbiter
Opportunity
Curiosity

Middle Solar System
Dawn (in transit to Ceres, arrival 2015)
Rosetta (in transit to comet 67P/Churyumov-Gerasimenko, arrival 2014)
Deep Impact (still operating, although not targeted at any other body)

Jupiter
Juno (in transit, arrival 2015)

Saturn
Cassini

Pluto
New Horizons (in transit, arrival 2015)

Leaving out the unfortunate omission of an ice giants spacecraft (Uranus and Neptune still possess many secrets for us to learn), that’s a pretty impressive record. The data coming in every day, not to mention the discovery of exoplanets in unexpected orbits around other stars, is resulting in an almost complete rewrite and constant revision of our understanding of the solar system. We are in a whirlwind of glorious data.

Another reason that the doom and gloom is premature is that—as some speakers at the history symposium emphasized—budgets are not destiny, and the current proposed planetary science budget is a proposed budget.

But perhaps the best reason to be wary of using past history as an indicator that things are likely to go from bad to worse, just as they have in times past, is that the political and policy environment that the planetary science program is operating in today is substantially different than the one that it operated in during the early 1980s.

Planetary science is now a legitimate discipline, taught by several universities, and accepted within larger and older scientific establishments. It has respectability, and visibility, that it previously lacked.

First, during the 1960s, in addition to the Jet Propulsion Laboratory, both NASA Ames and NASA Langley were involved in developing planetary science spacecraft. But by the 1970s a policy shift resulted in JPL assuming all responsibility for planetary spacecraft development. Thus, by the early 1980s, planetary science essentially meant JPL. Today that is no longer true. Although JPL still maintains a lead role in developing planetary spacecraft, NASA Ames was involved in the LCROSS lunar impactor mission and built the LADEE lunar spacecraft scheduled for launch in spring 2013, the Goddard Space Flight Center is developing the OSIRIS-REx asteroid sample return mission and MAVEN Mars orbiter, and the Applied Physics Lab has developed several recent spacecraft, including New Horizons and MESSENGER. The knowledge base of how to design, build and operate planetary science spacecraft is larger now than ever before.

Second, unlike previous decades, NASA now has dedicated planetary science program lines known as Discovery and New Frontiers. Program lines mean that the programs are funded at a relatively stable rate and NASA is allowed to select the missions without explicit executive or legislative approval. The value of this policy is that it prevents long gaps in planetary missions like occurred in the 1980s, and also alleviates the politicization of new program starts by establishing a regular cadence of missions. It can also help to avoid long gaps in visiting certain planetary bodies, such as the 22-year gap between Apollo 17 and the Clementine mission, or the 17-year gap between the Viking missions and the ill-fated Mars Observer.

Third, there are more planetary scientists working today than in the past. Planetary science is now a legitimate discipline, taught by several universities, and accepted within larger and older scientific establishments. It has respectability, and visibility, that it previously lacked. That has not automatically translated into political clout, but it does mean that planetary science has legitimacy.

So when looking back at the last fifty years of NASA’s planetary space program, we shouldn’t simply treat the events in isolation, but should look for trends, changes, and evolution.

Fourth, the method of selecting and prioritizing planetary science missions is much more established and defined now than it ever has been in the past. Beginning in 2001 the National Research Council produced the first planetary science decadal survey. In 2011, it produced the second. These documents provide the consensus opinion of the planetary science community. What this means is that there is a standard, commonly-accepted reference for new missions.

The people who ran NASA’s planetary programs in the past claim that they instituted changes to policies and programs precisely so that NASA can avoid some of the problems that it has encountered. In other words, they chose to learn from their history and change the present and future. A good question is whether or not they succeeded, even partially. The answer seems to be yes.

So when looking back at the last fifty years of NASA’s planetary space program, we shouldn’t simply treat the events in isolation, but should look for trends, changes, and evolution. Then again, maybe Clarence Darrow was right when he said “History repeats itself, and that’s one of the things that’s wrong with history.”


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