Image: Artist's concepts of Terrestral Planet Finder-Coronograph (left) and Terrestrial Planet Finder-Interferometer missions.
NASA
Artist’s concepts of Terrestral Planet Finder-Coronograph (left) and Terrestrial Planet Finder-Interferometer missions.
By
updated 6/6/2011 7:14:36 PM ET 2011-06-06T23:14:36

Geoff Marcy is mad.

Not mad as in "crazy," although many scientists thought he was nuts when he first started hunting for planets orbiting far-distant stars over 20 years ago. 

Now that over 500 exoplanets have been detected and the Kepler space telescope has over 1,200 candidate planets waiting to be confirmed, Marcy's dedication and hard work (and his sanity) have been vindicated.

But Marcy is still mad at NASA for canceling exoplanet missions like the Terrestrial Planet Finder (TPF) and the Space Interferometry Mission (SIM). He's also angered by what he sees as a lack of leadership and cooperation for exoplanet missions within NASA and the larger astrophysics community. [Gallery: The Strangest Alien Planets]

Marcy expressed his ire at a recent exoplanet symposium hosted by MIT planetary scientist Sara Seager."I'm unhappy about the last 10 years, and the next 10 years," he said.

Mission meltdowns
While the Kepler mission has been a huge success, and potentially will allow astronomers to discover a truly Earth-like planet, Marcy mourns the loss of other missions that would've helped characterize exoplanets, as well as find planets that Kepler could never detect.

"I think the case for TPF is more compelling thanks to Kepler," Marcy said.

The goal of TPF had been to study all aspects of exoplanets — according to a NASA web site, "from their formation and development in disks of dust and gas around nearly-forming stars, to their suitability as abodes of life."

Marcy criticized the 2010 astronomy and astrophysics Decadal Survey, an influential review complied by the National Research Council that recommends missions for space science over the next ten years.

"TPF was not even mentioned in the Decadal Survey," he said. "How is this possible?"

The previous Decadal Survey, released in 2001, had recommended that NASA proceed with TPF, with the caveat that astronomers first had to determine that terrestrial planets are common around sun-like stars. Data from Kepler and other exoplanet studiesindicate that this may in fact be the case. [Infographic: Stacking Up Alien Solar Systems]

  1. Space news from NBCNews.com
    1. KARE
      Teen's space mission fueled by social media

      Science editor Alan Boyle's blog: "Astronaut Abby" is at the controls of a social-media machine that is launching the 15-year-old from Minnesota to Kazakhstan this month for the liftoff of the International Space Station's next crew.

    2. Buzz Aldrin's vision for journey to Mars
    3. Giant black hole may be cooking up meals
    4. Watch a 'ring of fire' solar eclipse online

Marcy said that part of the blame for the current lack of large exoplanet missions should be placed on the scientific community, which did not advocate more strongly for TPF. Not too long ago, TPF was considered the most important and exciting mission for exoplanet science.

"I think TPF is our human genome project,” said Marcy. Without such a mission to help identify exoplanet characteristics, planet hunters become census-takers, just as astronomers 100 years ago counted the stars and put them into star category plots. "Now we count planets and put them into a period/radius diagram," he said.

Marcy said the astronomy community lost 10 years due to internal squabbling over which missions should receive funding. TPF scientists battled SIM scientists for supremacy, and then in 2004, when NASA decided to split TPF into two different missions — one with a coronagraph (TPF-C) and one with an interferometer  (TPF-I) — the problem only grew worse.

The coronagraph and interferometer each would block light from a star in order to detect any planets orbiting them.

The TPF-Interferometer would've had several small telescopes, either on a fixed structure or on separated spacecraft floating in formation, that looked for the infrared emission, or heat, from exoplanets. The TPF-Coronagraph would’ve used a single large mirror to collect the very dim reflected visible light from exoplanets.

In 2007, NASA deferred both TPF missions "indefinitely" due to budget constraints. 

"Free-flying interferometers in space are the only plausible future for astrophysics," Macy declared. He felt coronagraphs were not the best option, but noted that NASA saw it differently and supported TPF-C at the expense of other exoplanet missions. "Lots of interferometers and radial velocity missions got junked."

He said that some in the community, notably Roger Angel of the University of Arizona, had advocated for a cheaper, scaled-down version called TPF-Lite, but this was rejected because many feared it would eliminate motivation for a bigger TPF mission. 

"So now, we have nothing," said Marcy.

For awhile it looked like SIM was the last mission standing when it came to large-scale exoplanet missions after the cancelation of TPF. SIM would have surveyed the closest 100 stars, looking for planets of a few Earth-masses, using astrometry: the precise measurement of star movement caused by planetary orbits.

A scaled-down version, called SIM-Lite, wasnot recommended by the 2010 Decadal Survey for development.  Because of this, and despite the years of study and the $600 million NASA already had invested in the mission, SIM was canceled.

Marcy said there hasn't been any meaningful discussion about lessons learned after the downfall of TPF and SIM. 

"Where’s the insight?" he asked. "What's the culture that allows mistakes like this to happen?"

A house divided
Wesley Traub of the Jet Propulsion Laboratory seemed eager to address these criticisms. He jumped to his feet after Marcy spoke, and only reluctantly agreed to wait for the scheduled question-and-answer period.

Traub defended TPF-C, saying it had the advantage of being a single telescope that didn’t need to be cooled. However, he felt the switch in focus for TPF from interferometry to a coronograph was mainly due to perception than science. [Video: Kepler Reveals Lots of Planets: Some Habitable?]

  1. The planet boom
    1. Hunt for new worlds goes into overdrive
    2. Looking for alien Earths? Here they come
    3. Interactive: The new solar system
    4. Pluto debate is about more than one little world
    5. Cosmic Log: Planets on the Web
    6. Interactive: The search for extrasolar planets

Calling the history of exoplanet mission development a "sociology experiment," Traub said that interferometers were simply not popular -- they didn’t employ enough people, and students wanted to collect data, not dedicate their time to building a new instrument. 

But Traub, who worked on both SIM and TPF and is currently Chief Scientist for NASA's Exoplanet Exploration Program, also shared many of Marcy’s concerns about the state of exoplanet missions. Speaking about the cancellation of SIM, Traub said, "That was the most embarrassing thing I've seen in my life."

David Charbonneau, of the Harvard-Smithsonian Center for Astrophysics and a Kepler team member, spoke in support of the Decadal Survey. "If you're frustrated, read all the white papers."

Charbonneau said they reveal the caustic in-fighting that was taking place within the community which resulted in missions like SIM-lite not being recommended. Another problem, he said, was the lack of external cost evaluations, which could’ve helped in judging which missions were fiscally possible.

It was left to the symposium moderator, Sara Seager, to put in a good word for NASA, and she pointed out that the space agency had supported everyone gathered there that day. She also said that the current situation called to mind Abraham Lincoln’s phrase, "A house divided against itself shall not stand." 

Summing up the history of mission development, Seager said, "In exoplanets, we divided and got conquered."

The symposium, "The Next 40 Years of Exoplanets," took place May 27 at the Massachusetts Institute of Technology in Cambridge, Mass. This full day of talks also included discussions about astrobiology, Sara Seager's ExoPlanetSat, Geoff Marcy's call to send a mission to Alpha Centauri, and many other topics of relevance to exoplanets.

This story was provided to SPACE.com by Astrobiology Magazine. Follow SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.

© 2013 Space.com. All rights reserved. More from Space.com.

Video: New frontiers in planetary science

Photos: Month in Space: January 2014

loading photos...
  1. Southern stargazing

    Stars, galaxies and nebulas dot the skies over the European Southern Observatory's La Silla Paranal Observatory in Chile, in a picture released on Jan. 7. This image also shows three of the four movable units that feed light into the Very Large Telescope Interferometer, the world's most advanced optical instrument. Combining to form one larger telescope, they are greater than the sum of their parts: They reveal details that would otherwise be visible only through a telescope as large as the distance between them. (Y. Beletsky / ESO) Back to slideshow navigation
  2. A balloon's view

    Cameras captured the Grandville High School RoboDawgs' balloon floating through Earth's upper atmosphere during its ascent on Dec. 28, 2013. The Grandville RoboDawgs’ first winter balloon launch reached an estimated altitude of 130,000 feet, or about 25 miles, according to coaches Mike Evele and Doug Hepfer. It skyrocketed past the team’s previous 100,000-feet record set in June. The RoboDawgs started with just one robotics team in 1998, but they've grown to support more than 30 teams at public schools in Grandville, Mich. (Kyle Moroney / AP) Back to slideshow navigation
  3. Spacemen at work

    Russian cosmonauts Oleg Kotov, right, and Sergey Ryazanskiy perform maintenance on the International Space Station on Jan. 27. During the six-hour, eight-minute spacewalk, Kotov and Ryazanskiy completed the installation of a pair of high-fidelity cameras that experienced connectivity issues during a Dec. 27 spacewalk. The cosmonauts also retrieved scientific gear outside the station's Russian segment. (NASA) Back to slideshow navigation
  4. Special delivery

    The International Space Station's Canadian-built robotic arm moves toward Orbital Sciences Corp.'s Cygnus autonomous cargo craft as it approaches the station for a Jan. 12 delivery. The mountains below are the southwestern Alps. (NASA) Back to slideshow navigation
  5. Accidental art

    A piece of art? A time-lapse photo? A flickering light show? At first glance, this image looks nothing like the images we're used to seeing from the Hubble Space Telescope. But it's a genuine Hubble frame that was released on Jan. 27. Hubble's team suspects that the telescope's Fine Guidance System locked onto a bad guide star, potentially a double star or binary. This caused an error in the tracking system, resulting in a remarkable picture of brightly colored stellar streaks. The prominent red streaks are from stars in the globular cluster NGC 288. (NASA / ESA) Back to slideshow navigation
  6. Supersonic test flight

    A camera looking back over Virgin Galactic's SpaceShipTwo's fuselage shows the rocket burn with a Mojave Desert vista in the background during a test flight of the rocket plane on Jan. 10. Cameras were mounted on the exterior of SpaceShipTwo as well as its carrier airplane, WhiteKnightTwo, to monitor the rocket engine's performance. The test was aimed at setting the stage for honest-to-goodness flights into outer space later this year, and eventual commercial space tours.

    More about SpaceShipTwo on PhotoBlog (Virgin Galactic) Back to slideshow navigation
  7. Red lagoon

    The VLT Survey Telescope at the European Southern Observatory's Paranal Observatory in Chile captured this richly detailed new image of the Lagoon Nebula, released on Jan. 22. This giant cloud of gas and dust is creating intensely bright young stars, and is home to young stellar clusters. This image is a tiny part of just one of 11 public surveys of the sky now in progress using ESO telescopes. (ESO/VPHAS team) Back to slideshow navigation
  8. Fire on the mountain

    This image provided by NASA shows a satellite view of smoke from the Colby Fire, taken by the Multi-angle Imaging SpectroRadiometer aboard NASA's Terra spacecraft as it passed over Southern California on Jan. 16. The fire burned more than 1,863 acres and forced the evacuation of 3,700 people. (NASA via AP) Back to slideshow navigation
  9. Where stars are born

    An image captured by NASA's Spitzer Space Telescope shows the Orion Nebula, an immense stellar nursery some 1,500 light-years away. This false-color infrared view, released on Jan. 15, spans about 40 light-years across the region. The brightest portion of the nebula is centered on Orion's young, massive, hot stars, known as the Trapezium Cluster. But Spitzer also can detect stars still in the process of formation, seen here in red hues. (NASA / JPL-Caltech) Back to slideshow navigation
  10. Cygnus takes flight

    Orbital Sciences Corp.'s Antares rocket rises from NASA's Wallops Flight Facility on Wallops Island, Va, on Jan. 9. The rocket sent Orbital's Cygnus cargo capsule on its first official resupply mission to the International Space Station. (Chris Perry / NASA) Back to slideshow navigation
  11. A long, long time ago...

    This long-exposure picture from the Hubble Space Telescope, released Jan. 8, is the deepest image ever made of any cluster of galaxies. The cluster known as Abell 2744 appears in the foreground. It contains several hundred galaxies as they looked 3.5 billion years ago. Abell 2744 acts as a gravitational lens to warp space, brightening and magnifying images of nearly 3,000 distant background galaxies. The more distant galaxies appear as they did more than 12 billion years ago, not long after the Big Bang. (NASA / NASA via AFP - Getty Images) Back to slideshow navigation
  12. Frosty halo

    Sun dogs are bright spots that appear in the sky around the sun when light is refracted through ice crystals in the atmosphere. These sun dogs appeared on Jan. 5 amid brutally cold temperatures along Highway 83, north of Bismarck, N.D. The temperature was about 22 degrees below zero Fahrenheit, with a 50-below-zero wind chill.

    Slideshow: The Year in Space (Brian Peterson / The Bismarck Tribune via AP) Back to slideshow navigation
  1. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  2. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  3. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

  4. Editor's note:
    This image contains graphic content that some viewers may find disturbing.

    Click to view the image, or use the buttons above to navigate away.

Discuss:

Discussion comments

,

Most active discussions

  1. votes comments
  2. votes comments
  3. votes comments
  4. votes comments