Wednesday, February 25, 2015

Planetary scientist and author Dr. David Weintraub: Ceres and Pluto are Planets

Dr. David Weintraub, author of the excellent book Is Pluto A Planet, calls for reinstating planet status to both Ceres and Pluto as the result of new information bring provided by NASA's Dawn and New Horizons mission respectively.

The public definitely agrees. In this poll, a whopping 88 percent of participants voted that Pluto is a planet!:

Wednesday, February 18, 2015

85 Years of Pluto

Eighty-five years ago today, on February 18, 1930, 24-year-old Clyde Tombaugh discovered the planet Pluto using a blink comparator to “blink” back and forth between photographic plates of the same section of the sky taken several days apart using the Lowell Observatory’s 13-inch astrograph—a telescope equipped with a camera.

The faint, tiny dot Tombaugh discovered moving against the background stars was so tiny and remote that telescopes of the day could not resolve it into a disk. That led some astronomers, including Tombaugh, to speculate that the object discovered was the moon of a larger planet, yet to be found.

It wasn’t.

The Lowell Observatory declared the object the planet sought in a search it sponsored since the days of founder Percival Lowell.

And in the depths of the Great Depression, excitement spread. Finally, there was some good news—a new planet found in what was then believed to be the outer reaches of the solar system.

Even more encouraging, the planet was found not by someone coming from a lifetime of privilege like Lowell, who funded the construction of his own observatory, but from a farm boy who succeeded through intelligence, determination, and grit.

In the span of a human lifetime, little Pluto has thrilled, fascinated, excited, and challenged countless people from professional astronomers and planetary scientists to children. The only experience it has not created among people is boredom.

Now, just five months from New Horizons’ closest flyby, Pluto again has celebrity status. It is everywhere in the media.

In honor of the 85th anniversary of Pluto’s discovery, the New Horizons mission released the first images of tiny moons Nix and Hydra, taken with the spacecraft’s Long Range Reconnaissance Imager or LORRI, between January 27 and February 8. The photos were taken from distances of 125 million and 115 million miles of the small planet.

With so much media attention, the debate over Pluto’s status, a matter still in limbo, inevitably resurfaces in articles both print and online.

Many of these articles point to 2006 as the time the debate over Pluto ignited, not realizing that that debate goes much further back.

Not only did the debate not begin in 2006; it also did not begin in 2001, when Neil de Grasse Tyson set up a solar system display in the American Museum of Natural History that excluded Pluto; or in 1999, when the late Brian Marsden of the IAU Minor Planet Center proposed giving Pluto a minor planet number; or even in 1992, when the first Kuiper Belt Object other than Pluto was discovered.

What so many do not know is that the debate what Pluto is began in 1930, immediately upon its discovery, and continued unabated for decades. It was not always front and center, given how little was known about this tiny world.

Only one month after the announcement of Pluto’s discovery, the New York Times reported astronomers questioning planet status. “It is now thought it may prove to be a unique asteroid or an extraordinary comet-like object,” an unnamed astronomer was quoted as saying.

Similar questions were raised in a 1930 Scientific American article by Dr. Henry Norris Russell; in a 1931 Popular Astronomy article by Dr. William Pickering; in a 1934 article published in Everyday Science and Mechanics; in a 1950 Sky and Telescope article by Dr. Dirk Brouwer of Yale University; and a 1968 Sky and Telescope article by Dr. Dennis Rawlins.

Each article raised the same questions regarding Pluto’s mass, size, composition, and orbit, all of which were unique in the solar system.

Over time, Pluto’s mass and size were revised downward, until James Christy discovered Pluto has a moon, Charon, that is half Pluto’s size. The two objects are separated by only 12,200 miles. Pluto’s size had so long been overestimated because astronomers had not realized that they were looking at two objects rather than one.

Meanwhile, several opportunities to study Pluto were missed. When Voyager 1 launched in the late 1970s on a “Grand Tour” of the gas and ice giant planets, some scientists wanted to use a gravity assist from Saturn to send the spacecraft to Pluto. That option was ultimately rejected in favor of a close flyby of Saturn’s moon Titan.

When Voyager 2 completed the “Grand Tour” in 1989 with a flyby of Neptune, a group of dedicated planetary scientists, many of whom are on the New Horizons team, began advocating a mission to Pluto. At the time, Pluto was at perihelion, its closest approach to the Sun, a prime location for study.

Several times, mission plans were drawn up only to be canceled due to lack of funding, before NASA finally approved New Horizons in November 2001. More than four years would pass from then until launch on January 19, 2006.

Clyde Tombaugh lived long enough to know that a mission to the planet he discovered was in the works. In 1992, Jet Propulsion Laboratory researcher Robert Staehle approached Tombaugh asking permission to visit “his” planet.

“I told him he was welcome to it though he’s got to go on one long, cold trip,” Tombaugh said.

Tombaugh died three weeks before his 91st birthday, in January 1997. Some of his ashes are in a container onboard New Horizons. His late widow Patricia and family members attended the spacecraft’s launch.

Tombaugh did not live to see the discoveries of Nix, Hydra, Kerberos, or Styx. He died believing his planet had just one moon, albeit a large one.

At the time of Pluto’s discovery, Tombaugh was given little recognition. The Lowell Observatory’s announcement did not even mention his name, instead referring to him as “an assistant on the staff.” The name most invoked and praised regarding the discovery was Percival Lowell.

The story of Pluto and its discoverer are inextricably linked. Both are of underdogs who defied the odds to eventually gain unprecedented popularity that continued over decades. A planetarium instructor recently listed Pluto as one of the leading subjects about which children ask her. The mysterious little planet on the frontiers of the solar system continues to inspire, to elicit awe and wonder, to generate tremendous interest, even in today’s world of short attention spans.

“Professor Tombaugh’s discovery was far ahead of its time, heralding the discovery of the Kuiper Belt and a new class of planet. The New Horizons team salutes his historic accomplishment,” noted New Horizons principal investigator Dr. Alan Stern.

If only Tombaugh could see his discovery now, moons and all!

Here are some of the latest celebrations of Pluto:

In Flagstaff, Arizona, where Pluto was discovered: and and

In Nashville, Tennessee, through space science educator Janet Ivey:

In Denver, Colorado:

From author Homer Hickham in Huntsville, Alabama:

On Facebook, by the Society of Unapologetic Pluto Huggers:

On the website Spaceflight Insider:

By the New Horizons mission:

Another Poll: Vote for Pluto to be classed as a planet!

Once again, elementary school kids prove themselves smarter and more understanding of the solar system than the leadership of the IAU and 424 particular members. Click on this link, and scroll down to find the poll question, then vote yes, Pluto is a planet!

Wednesday, January 28, 2015

Another Online Poll: Vote for Pluto to be Classed as a Planet!

With Pluto getting so much attention as New Horizons begins its reconnaissance of the planet and its moons, yet another publication online, the British, has posted a poll asking whether Pluto should be classed as a planet.
Please visit , read the article, and scroll down to the poll, "Should Pluto be Classified as a Planet?" and vote yes!

Voting is open to all. You do not have to be British or have an account with the site to participate.

Tuesday, January 27, 2015

Pluto and the Solar System: A Google+ Hangout with NASA and PBS Learning Media

How many times has the issue of education about the solar system come up over the past eight years? The Great Planet Debate of 2008 hosted a workshop for elementary and secondary teachers on teaching the controversy rather than just stating the solar system has such and such number of planets, and that's it, case closed. Tomorrow night, Wednesday, January 28, from 7-8 PM EST, NASA and PBS Learning Media are hosting a Google+ hangout to discuss educating students about the New Horizons mission. If you do not have an account on Google+, you can create one for free. Everyone who joins the hangout will be able to ask questions through a chat box. Participation in the hangout is free as well. Do not miss this opportunity. You do not have to be a teacher or formal instructor to attend.

Here is the link:

From the site:

"We are going to Pluto this year for the first time with the New Horizons mission! How do you bring your science students along for the ride, and what updates and changes await your Solar System curriculum in the year ahead? PBS LearningMedia™ and NASA are here to help with an inside look at what lies ahead for Solar System science, with a particular focus on pedagogical changes and new educational resources to help your curriculum stay up-to-date in this exciting time for space exploration.

Jeffrey M. Moore, New Horizons Co-Investigator, NASA Ames Research Center
Jeff is the imaging team leader for the New Horizons mission. This activity involves working with the imaging team to define the science observations, plan the observational sequences, and calibrate the camera system. He also served as Chairman of the Jupiter Encounter Sequencing Team for the New Horizons mission, which enjoyed a very successful encounter with the giant planet and its moons in 2007.

Keri Hallau, Montana State University, Department of Physics
Keri Hallau is the Formal Education lead on the Education and Communication team for the New Horizons mission to Pluto. In addition, as the Online Science Curriculum Development Specialist for the Montana State University Department of Physics, she creates curriculum materials for various other NASA missions that include the Cassini-Huygens mission to Saturn and Titan, the New Horizons mission to Pluto, and the MESSENGER mission to Mercury.

Rachel Connolly, Director of STEM Education, WGBH

NGSS standards addressed will include:

MS-ESS1-3. Analyze and interpret data to determine scale properties of objects in the solar system.

ESS1.B: Earth and the Solar System
The solar system consists of the sun and a collection of objects, including planets, their moons, and asteroids that are held in orbit around the sun by its gravitational pull on them. (MS-ESS1-2),(MS-ESS1-3)"