Subscribe free to our newsletters via your
. 24/7 Space News .




OUTER PLANETS
Sharpest-ever Ground-based Images of Pluto and Charon: Proves a Powerful Tool for Exoplanet Discoveries
by Staff Writers
Hilo, HI (SPX) Sep 27, 2012


Speckle image reconstruction of Pluto and Charon obtained in visible light at 692 nanometers (red) with the Gemini North 8-meter telescope using the Differential Speckle Survey Instrument (DSSI). Resolution of the image is about 20 milliarcseconds rms (root mean square). This is the first speckle reconstructed image for Pluto and Charon from which astronomers obtained not only the separation and position angle for Charon, but also the diameters of the two bodies. North is up, east is to the left, and the image section shown here is 1.39 arcseconds across. Credit: Gemini Observatory/NSF/NASA/AURA.

Despite being infamously demoted from its status as a major planet, Pluto (and its largest companion Charon) recently posed as a surrogate extrasolar planetary system to help astronomers produce exceptionally high-resolution images with the Gemini North 8-meter telescope.

Using a method called reconstructive speckle imaging, the researchers took the sharpest ground-based snapshots ever obtained of Pluto and Charon in visible light, which hint at the exoplanet verification power of a large state-of-the-art telescope when combined with speckle imaging techniques.

The data also verified and refined previous orbital characteristics for Pluto and Charon while revealing the pair's precise diameters.

"The Pluto-Charon result is of timely interest to those of us wanting to understand the orbital dynamics of this pair for the 2015 encounter by NASA's New Horizons spacecraft," said Steve Howell of the NASA Ames Research Center, who led the study. In addition, Howell notes that NASA's Kepler mission, which has already proven a powerful exoplanet discovery tool, will benefit greatly from this technique.

Kepler identifies planet candidates by repeatedly measuring the change in brightness of more than 150,000 stars to detect when a planet passes in front of, or affects the brightness of, its host star.

Speckle imaging with the Gemini telescope will provide Kepler's follow-up program with a doubling in its ability to resolve objects and validate Earth-like planets.

It also offers a 3- to 4-magnitude sensitivity increase for the sources observed by the team. That's about a 50-fold increase in sensitivity in the observations Howell and his team made at Gemini. "This is an enormous gain in the effort underway to confirm small Earth-size planets," Howell added.

To institute this effort Howell and his team - which included Elliott Horch (Southern Connecticut State University), Mark Everett (National Optical Astronomy Observatory), and David Ciardi (NASA Exoplanet Science Institute/Caltech) - temporarily installed a camera, called the Differential Speckle Survey Instrument (DSSI), among the suite of instruments mounted on the Gemini telescope.

"This was a fantastic opportunity to bring DSSI to Gemini North this past July," said Horch. "In just a little over half an hour of Pluto observations, collecting light with the large Gemini mirror, we obtained the best resolution ever with the DSSI instrument - it was stunning!"

The resolution obtained in the observations, about 20 milliarcseconds, easily corresponds to separating a pair of automobile headlights in Providence, Rhode Island, from San Francisco, California.

To achieve this level of definition, Gemini obtained a large number of very quick "snapshots" of Pluto and Charon. The researchers then reconstructed them into a single image after subtracting the blurring effects and ever-changing speckled artifacts caused by turbulence in the atmosphere and other optical aberrations.

With enough snapshots (each image was exposed for only 60 milliseconds or about 1/20 of a second) only the light from the actual objects remains constant, and the artifacts reveal their transient nature, eventually canceling each other out.

DSSI was built at SCSU between 2007-2008 as a part of a United States National Science Foundation Astronomical Instrumentation grant and mounted on the Gemini North telescope for a limited observing run. The instrument is likely to return to Gemini North for observations in mid-2013 for general user programs from across the international Gemini partnership. Any such arrangement will be announced along with the call for proposals for Semester 13B, in February 2013.

This work was funded in part by the National Science Foundation and NASA's Kepler discovery mission and will be published in the journal Publications of the Astronomical Society of the Pacific in October 2012.

.


Related Links
Gemini Observatory
The million outer planets of a star called Sol






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








OUTER PLANETS
The Kuiper Belt at 20: Paradigm Changes in Our Knowledge of the Solar System
Boulder CO (SPX) Aug 29, 2012
New Horizons remains healthy and on course, now more than 24 times as far from the Sun as the Earth is. This summer's spacecraft and payload checkout went extremely well, as did both major flight-software updates we loaded aboard New Horizons. And, the spacecraft's rehearsal of the closest-approach day of the Pluto encounter went just about perfectly. After finishing all of this at the beg ... read more


OUTER PLANETS
China has no timetable for manned moon landing

Senior scientist discusses China's lunar orbiter challenges

NASA sees 'gateway' for space missions

Protection for Moon, Mars astronauts eyed

OUTER PLANETS
A windshield wiper for Mars dust

Curiosity Finishes Close Inspection of Rock Target

Where is Deimos?

Professor says NASA's Martian weather reports show extreme pressure swings

OUTER PLANETS
B612 Wins Funding Support From Prominent Business Leadersy

Cavenauts return to Earth

Brazil unveils tax incentives to boost tech innovation

New Technology Being Stymied by Copyright Law

OUTER PLANETS
China Spacesat gets 18-million-USD gov't support

Tiangong Orbit Change Signals Likely Date for Shenzhou 10

China Focus: Timeline for China's space research revealed

China eyes next lunar landing as US scales back

OUTER PLANETS
Russia to send all-novice crew to ISS

ATV undocking postponed

Crew Members Prepare for Departure

ISS Crew Lands Safely in Kazakhstan

OUTER PLANETS
California Governor Signs the Spaceflight Liability and Immunity Act

Processing is underway with the next Automated Transfer Vehicle to be orbited by Arianespace

Fueling underway with the Galileo satellites for next Soyuz launch from French Guiana

SpaceX, NASA Target Oct. 7 Launch For Resupply Mission To Space Station

OUTER PLANETS
Meteors Might Add Methane to Exoplanet Atmospheres

Two 'hot Jupiters' found in star cluster: NASA

Planets Can Form in the Galactic Center

Birth of a planet

OUTER PLANETS
Pigs' revenge as 'Angry Birds' makers launch new game

Basing of first US Space Fence facility announced

US Bank admits 'attacks,' says customer data safe

Date palm juice: A potential new 'green' anti-corrosion agent for aerospace industry




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement