Elite eight; Kepler finds more potentially Earth-like exoplanets

We still don’t know whether we’re alone in the universe, but there’s been some exciting progress in the search.

“We are now closer than we have ever been to finding a twin for the Earth around another star,” according to Fergal Mullally, SETI Institute Kepler scientist at NASA/Ames Research Center. Mullally spoke at a news conference about the latest discoveries regarding exoplanets, held in Seattle Jan. 6 at the 225th meeting of the American Astronomical Society.

The Kepler team announced a new bunch of exoplanet candidates and added three new confirmed exoplanets to the list of those that are about the size of Earth and in the habitable zone of their parent star. It’s still a short list.

Kepler HOF“We have significantly increased the number of these verified, small, habitable-zone planets from Kepler,” said Doug Caldwell, another SETI Institute Kepler scientist at Ames. “They really make up a special population that is of interest for understanding the prevalence of life in the universe. Yesterday we had five Kepler exoplanets in this special hall of fame; today we have eight in this elite club.”

“These are the planets that Kepler was designed to find, and we’re delighted to be finally finding them,” Mullally added.

The Kepler crew also announced 554 new exoplanet candidates, bringing the total from the mission to 4,175. More than a thousand of those are now verified planets.

Of the elite eight, Caldwell said two are likely to be rocky, Kepler 438b and 442b, and three others are pegged as potentially rocky. There’s a lot of uncertainty about those numbers as the research continues.

While most exoplanets have been discovered by spotting their transits or measuring radial velocity, there may be nothing better than a visual look. So far, though, scientists have only been able to image a few planets around faraway stars, mostly huge planets far from their stars.

“It’s the tip of the iceberg, the easiest planets to see,” said Marshall Perrin of the Space Telescope Science Institute. “Easy is relative; these planets are about a million times fainter than their parent stars and are a small fraction of an arcsecond from them.”

Perrin, however, is heading up the Gemini Planet Imager (GPI), which saw first light about a year ago at the Gemini South Observatory in Chile and holds great promise to improve exoplanet imaging. While much of its first year was spent getting set up and working out the bugs, GPI also made some interesting and detailed observations of exoplanets.

GPI is about the size of an automobile.

Conference

The AAS exoplanet news conference on Jan. 6 at AAS225. Left to right: moderator Larry Marschall, deputy press officer of AAS, Kepler scientists Fergal Mullally and Doug Caldwell, Marc Kuchner of Goddard, and Marshall Perrin of STSci.

“What’s inside the box is a lot of sophisticated technology,” Perrin said, including, “an adaptive optic system to correct for atmospheric jitter and deliver images with the same sharpness for the specific stars we’re looking at that the James Webb will see in space several years from now.”

The advantages of imaging are that you don’t have to wait for full orbits to confirm planets, and you can start taking spectra that can reveal a lot about the nature of the planets.

“In the long run we think that imaging offers perhaps the best path to characterizing rocky planets in Earth-like orbits,” Perrin said. He notes that GPI is gearing up for more science.

“We’re going to be opening up a lot of new discoveries, hopefully, over the next few years in terms of exoplanet imaging and, in the long run, taking these technologies and scaling them to future 30-meter telescopes, perhaps large telescopes in space.”

Marc Kuchner of NASA Goddard Space Flight Center is marshaling a huge cadre of volunteers working to identify disks of potentially planet-forming material around distant stars. NASA’s WISE mission found hundreds of thousands of possible sources. It’s the sort of data that takes a human eye to sort out, so NASA fired up DiskDetective.org, in connection with Zooniverse, to involve volunteers. More than 28,000 of them have made a million characterizations through the site in its first year.

“They found 478 objects of interest so far,” Kuchner noted. Once one of those is identified they get some telescope time for a closer look.

“We now have at least 37 solid new disk candidates, and we haven’t even looked at all the new telescope data yet,” Kuchner said. He invites more volunteers to visit the site and join in the effort to identify places where planets may form and we might spot other Earths.

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Rosetta mission: the end of the beginning

There have been a lot of amazing space missions that rank among the greatest engineering achievements of all time. The Rosetta mission has to be one of the most impressive ever. Rosetta traveled 10 years and more than four billion miles to rendezvous with comet 67P/Churyumov-Gerasimenko, a rubber-ducky-shaped pile of rocks 2.5 miles across that is zipping through space at about 84,000 miles an hour. It went into orbit around the comet and then it dropped a lander, Philae, that touched down on the surface of the comet back in November. Never mind that Philae didn’t stick the landing; that’s an quite an accomplishment.

Paul Weissman

Paul Weissman of JPL spoke about the Rosetta mission Monday at the 225th meeting of the American Astronomical Association.

Thus it was most enjoyable to hear from one of the Rosetta mission scientists, Paul Weissman of the NASA Jet Propulsion Laboratory, on Monday afternoon at the 225th meeting of the American Astronomical Society. Weissman gave a talk titled “Back to the Beginning: The Rosetta Mission to Comet Churyumov-Gerasimenko.”

“Doing space missions is a work of delayed gratification,” Weissman quipped, noting that they actually started work on Rosetta in 1996, and adding that there had been plans for such a mission for about a decade before that. They finally launched in 2004 and arrived at the comet, often shortened to C-G for obvious reasons, back in August.

“We had been ten years in space,” Weissman said. “It was really exciting to finally arrive at the comet.”

Rosetta carries 11 scientific instruments on board, and the Philae has ten. Even though Philae didn’t operate for long, between them the two craft have sent back a wealth of data.

“We’ve just been flooded with phenomenal results,” Weissman said.

Philae on C-G

Rosetta’s lander Philae on the surface of Comet 67P/Churyumov-Gerasimenko. One of the lander’s three feet can be seen in the foreground. The image is a two-image mosaic. Credit: ESA/Rosetta/Philae/CIVA

He shared a great many photographs from the mission and explained what all of the instruments have been observing. Among the interesting discoveries are that C-G is spinning faster than it did on its previous trip around the Sun, the result of the forces of outgassing of the comet’s material. There are pits on the nucleus that may be sink holes or outbursts; they’re not quite sure yet. They’ve detected water within the comet, and learned it is colder in its interior than on the surface. And the comet has about 74 percent porosity.

Some of the most fantastic returns are images taken by Philae from the surface of C-G that show exquisite detail.

“We’re looking at millimeter resolution of the surface of the comet,” Weissman noted, “something that’s just astounding in terms of what we’ve been able to do previously.”

Weissman holds out hope that they’ll get more from Philae, even though its batteries are dead because it landed in the shade.

“It may be possible to re-awaken the lander in May of this year,” he noted. “The solar panels that are exposed will gather enough energy to charge up the batteries, and we might have another shot of making measurements with the lander.”

Whether that works or not, there already is a great deal of data that mission scientists simply have not yet had time to analyze, and there’s more to come.

“This is the end of the beginning,” Weissman said, “because we have another whole year that we’re going to be in orbit, studying the nucleus and watching it get active. It reaches perihelion in August, so we’ll also watch it get inactive. And there’s talk of an extended mission into 2016.”

“This is just a remarkable mission.”

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A dim view of the future of funding for space exploration

Dr. John M. Logsdon does not paint a very optimistic picture of the future of funding for space exploration. Logsdon, considered the dean of space policy and the founder of the Space Policy Institute at George Washington University, gave a talk titled “What Do We Expect of a Space Program?” today at the 225th meeting of the American Astronomical Society in Seattle.

John Logsdon

Dr. John Logsdon speaking Jan. 5, 2015, at the 225th meeting of the American Astronomical Society in Seattle.

Logsdon pulled the title of his lecture from a line in a Nixon Administration memo about the future of the space program. He says a big part of the problem is that, in more than four decades since the memo, the underlying question has not been adequately answered.

Logsdon pins much of the blame for the situation on President Nixon, who scaled back funding for NASA after the race to the Moon was won.

“The decisions he made from the ’69 through ’71 period, culminating in the January 5, 1972 announcement of the approval of the space shuttle, really characterized the program that NASA executed for the next 40-plus years, and basically avoided answering the question ‘What do we expect?’ by developing capabilities rather than seeking goals,” Logsdon said.

We had the answer under President Kennedy, according to Logsdon, when the goal was not just to put people on the Moon, but to achieve preeminence about all things in outer space.

“What is distinctive about Kennedy is he not only talked the talk, but he walked the walk,” Logsdon said. “He made a commitment of human and financial resources, peaceful but warlike mobilization of resources, to carry out that program of preeminence.”

Logsdon pointed out that the budget for NASA was $964 million when JFK urged the US to go the Moon; it had ballooned to $5.2 billion by 1965. Space science shared in the growth, its part of the NASA budget going from $131 million to $767 million in the same time frame.

Logsdon is tackling the history of presidential support for space exploration in his scholarship. He published John F. Kennedy and the Race to the Moon in 2010. His new book, After Apollo?: Richard Nixon and the American Space Program, is due out in March. The latter goes into great detail about Nixon’s approach and its lasting impact.

While NASA’s budget has fluctuated over the years, Logsdon sees a silver lining in the nation’s investment in science.

“The ups and downs in the overall NASA budget are not reflected in the budget for space science, which has shown a rather gradual but steady increase for the past 25 or 30 years, and has not vacillated,” he said. “Compared to the human spaceflight part of NASA, the space science, robotic science program, including Earth science, is in pretty good shape and is not being argued about.”

Logsdon served on the Columbia Accident Investigation Board, which opined in 2003 that NASA was being forced to do too much without adequate resources. He said that’s still a problem. The reason he doesn’t see a good solution ahead is that there are three possible responses, two of which he views as unlikely. He doesn’t foresee a great increase in our ambitions or some Sputnik-like incident that creates urgency about space. Nor does he anticipate a significant increase in spending, though that could depend in part on who the next president turns out to be.

“The most likely outcome is that we just keep muddling along, as we have since 1971, with a suboptimal program,” he concluded.

Further reading:

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Shields up! Scientists find impenetrable barrier around Earth

Planet Earth has an invisible and impenetrable shield about 7,200 miles out in space that blocks killer electrons from coming in and zapping satellites and causing all sorts of other havoc in the wake of huge coronal mass ejections from the Sun. This barrier is a major discovery of the Radiation Belt Storm Probe and the Relativistic Electron Proton Telescope (REPT), launched by NASA in August of 2012.

Baker

Dr. Daniel Baker

Dr. Daniel Baker, REPT science lead at the Laboratory for Atmospheric and Space Physics at the University of Colorado, spoke about the mission and the discoveries today during his opening lecture at the 225th meeting of the American Astronomical Association in Seattle. The discoveries were detailed in an article in Nature back in November.

Baker has some great credentials for the project. He earned his Ph.D. under James Van Allen, whose gear first detected the Van Allen Belts—he preferred to call them zones—in 1957, in what many consider to be the first major scientific discovery of the space age. Baker also was an investigator on SAMPEX, a particle exploring mission that operated from 1992 until 2004.

There are twin REPT probes in a highly elliptical orbit around the Sun. One of the first major discoveries by REPT, according to Baker, was of a third Van Allen Belt, a storage belt of ultra-relativistic particles that remains constant while the other belts vary wildly because of solar events.

Interestingly enough, these particles don’t ever get in any closer than about 2.8 Earth radii. Baker says that was a strange discovery, as nature typically doesn’t like such sharp barriers, but observations so far have shown it to be an impenetrable.

“It looks, at least for the period of time, the couple of years, since the Van Allen probe launched that particles—ultrarelativistic electrons—can get in so far, they run into something almost like a glass wall, and can’t really get any further. This really was quite an interesting and fascinating puzzle.”

They looked into whether the phenomenon might be related to various actions of the Earth’s magnetic field, or even perhaps a reaction to radio waves broadcast from Earth, but those explanations fell short.

“We were left with the unsatisfying situation that very slow pitch-angle scattering and even slower radial diffusion can conspire to create this sharp gradient in the particle distributions,” Baker said. “To me, that’s not very satisfactory, but it seems to be the explanation.”

“I think its a subject now that our theoretical friends are struggling with and trying to understand and explain,” he added.

Baker says this new information is vitally important for those who may be studying x-rays from the Sun, synchrotron emissions from Jupiter, radio and x-ray emissions from distant nebulae, or extra-gallactic jets.

“All of these are visible because of energetic particles, electrons primarily, moving in strong magnetic fields,” he said. “Examining the details of how the accelerator that is so accessible to us in our own cosmic backyard can really give us much useful information about how acceleration processes work in these more removed systems.”

Baker says it is an exciting time in the field, with a great many instruments and missions collecting data.

“We have quite a golden age, in a sense, of measuring the properties of this entire magnetospheric system,” he said. “When we combine this information that we’re gathering now with the wonderful measurements of the Sun and the driving factors from the Sun, we really have the opportunity to make immense progress and to address the key questions that Van Allen and co-workers uncovered nearly 60 years ago.”

“The results from the Van Allen probes mission have in a real sense been rewriting the textbooks on many aspects of structure, acceleration, transport, and loss,” Baker concluded. “They’re giving us previously undreamt of capabilities.”

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Tenth anniversary of the beginning of the end for Pluto

It’s hard to believe it has been a decade already since Mike Brown and his Caltech team discovered the dwarf planet Eris and inadvertently kicked off the brouhaha that eventually resulted in Pluto being “demoted” from its status as our solar system’s ninth planet. Brown and company discovered Eris on January 5, 2005, from images shot in October 2003.

How I Killed PlutoSome years later we read three books about the demotion of Pluto: Brown’s How I Killed Pluto and Why It Had It Coming; Neil deGrasse Tyson’s The Pluto Files: The Rise and Fall of America’s Favorite Planet; and The Case for Pluto: How a Little Planet Made a Big Difference by Alan Boyle, science editor for NBCNews.com and author of Cosmic Log.

All three books are great reads; I reviewed them in 2011 and noted that the authors voted 2-1 in favor of Pluto’s demotion as a planet. Boyle cast the lone dissenting vote. Brown’s book was especially interesting for its inside story of how the discovery came about, and how the search for Trans-Neptunian Objects changed his life. It may well be worth a re-read this month on the ten-year anniversary of the discovery.

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The Super Bowl of astronomy hits Seattle

They’re calling it the Super Bowl of Astronomy, and while we don’t expect cheerleaders shaking their pom-pons or legions of blue-clad number twelves chanting “caw” at a plenary talk about Fermi bubbles or at a poster session about emerging multiwavelength views of planetary nebulae, some 2,600 astronomers, planetary scientists, educators, and journalists will hit the Washington State Convention Center in Seattle for the winter meeting of the American Astronomical Society today through Thursday.

aas_225web_bannerSeattle Astronomy will be on hand, though this is the stargazer’s version of a 415,000-square-foot candy store; with 1,900 scientific presentations crammed into the five days, it’s hard to know where to start! We’ve sketched out a tentative schedule, starting with the welcome address Monday morning and a talk by University of Colorado astronomer Daniel Baker about new discoveries about the Van Allen Belts. We won’t likely call it quits until after a town hall session about the Hubble Space Telescope Thursday afternoon.

A couple of satellite events have sprung up because of the presence of so many astronomy professionals in town. Tuesday evening at Town Hall Seattle the Springer Storytellers will feature five astronomers and their tales of exploration, part of Springer Publishing’s Story Collider project. Wednesday evening at the Museum of Flight NASA astrophysicist Amber Straughn will talk about the James Webb Space Telescope, scheduled to launch in 2018. Friday the Boeing Employees Astronomical Society will hold its holiday banquet, to be keynoted by Robert Nemiroff, founder of the popular website Astronomy Picture of the Day. Follow the links for details about these events.

Information about the AAS meeting is online at the AAS website. If you want to follow on social media, conference participants will be using the hashtag #aas225 with their posts. The AAS is on Twitter at @AAS_Office, and on Facebook as well.

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Comet hunter Machholz to keynote annual Seattle Astronomical Society banquet

Don Machholz

Comet hunter Don Machholz will keynote the Seattle Astronomical Society annual banquet Jan. 24.

The Seattle Astronomical Society always seems to score interesting speakers for its annual banquet, and this year is no exception. Renowned comet hunter Don Machholz will give the keynote talk at the 2015 banquet Saturday, January 24, at the Swedish Club, 1920 Dexter Avenue North in Seattle.

Machholz is a prolific comet finder; he has eleven comet discoveries listed to his credit. The first was Machholz 1978L, discovered in September of that year after more than 1,700 hours of observing. The most recent was comet C 2010 F4 (Machholz). All of his discoveries have been made visually, quite a record in these days of digital cameras, computers, and space telescopes joining in the hunt.

Machholz is also considered to be one of the creators of the Messier marathon, an challenge to astronomers to observe all 110 objects in Charles Messier’s catalog in one night. Machholz has written a guidebook, The Observing Guide to the Messier Marathon: A Handbook and Atlas, published by Cambridge University Press in 2002.

Machholz has written several other books. Decade of Comets chronicles the comets discovered visually between 1975 and 1984. An Observer’s Guide to Comet Hale-Bopp came out in 1996.

It should be a most interesting evening.

Tickets to the banquet have been available for members of the Seattle Astronomical Society for several weeks, and went on sale to the general public today. The cost is $40 for members, and $50 for non-members. But why not sign up? Membership is just $35 annually. The Jan. 24 event will begin with a happy hour at 5 p.m., followed by a buffet dinner at 6 p.m. and the program at 7 p.m.

Further reading:

Don Machholz website

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