Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Volcano Loki Observed from Earth

04.05.2015

With the first detailed observations of a lava lake on a moon of Jupiter, the Large Binocular Telescope Observatory in Arizona places itself as the forerunner of the next generation of Extremely Large Telescopes. The applied high-resolution imaging methods were developed by an international research team including scientists from the Max Planck Institute for Radio Astronomy in Bonn and the Max Planck Institute for Astronomy in Heidelberg.

Io, the innermost of the four moons of Jupiter discovered by Galileo in January 1610, is only slightly bigger than our own Moon but is the most geologically active body in our solar system. Hundreds of volcanic areas dot its surface, which is mostly covered with sulfur and sulfur dioxide.


The LBT image of the Loki lava lake (orange) laid over a Voyager image of the same structure (dark shade).

LBTO / NASA


Jupiter's moon Io seen by LBT (left) compared to a NASA satellite image (right). The Loki lava lake shows up as dark red region on the LBT image. The circles mark the volcanos in the LBT image.

LBT Research Team

The largest of these volcanic features, named Loki after the Norse god often associated with fire and chaos, is a volcanic depression called patera in which the denser lava crust solidifying on top of a lava lake episodically sinks in the lake, yielding a raise in the thermal emission which has been regularly observed from Earth. Loki, only 200km in diameter and at least 600 million km from Earth, was, up to recently, too small to be looked at in details from any ground based optical/infrared telescope.

With its two 8.4 m mirrors set on the same mount 6 m apart, the Large Binocular Telescope (LBT) has been designed to ultimately provide images with the level of details a 22.8 m telescope would, by combining the light through interferometry. Thanks to the Large Binocular Telescope Interferometer (LBTI), an international team of researchers was able to look at Loki Patera in details for the first time from Earth in a study published today in the Astronomical Journal.

"We combine the light from two very large mirrors coherently so that they become a single, extremely large mirror,” says Al Conrad, the lead of the study and a Scientist at the Large Binocular Telescope Observatory (LBTO). “In this way, for the first time we can measure the brightness coming from different regions within the lake."

For Phil Hinz, who leads the LBTI project at the University of Arizona Steward Observatory, this result is the outcome of a nearly fifteen year development. "We built LBTI to form extremely sharp images. It is gratifying to see the system work so well." Phil notes that this is only one of the unique aspects of LBTI. "We built the system both to form sharp images and to detect dust and planets around nearby stars at extremely high dynamic range. The new result from LBTI is a great example of its potential."

LMIRcam, the camera recording the images at the very heart of LBTI in the 3 to 5 micrometers near-infrared band, was the thesis work of Jarron Leisenring as graduate student at the University of Virginia. For Jarron, now an instrument scientist for NIRCam (the Near InfraRed CAMera for the James Webb Space Telescope) at Steward Observatory, "these observations mark a major milestone for me and the instrument team. LMIRcam has already been very productive these past few years; now, interferometric combination provides the last step in harnessing LBTI’s full potential and enabling a whole host of new scientific opportunities."

Many raw images delivered by LMIRcam are combined to form a single high-resolution image. "LBTI raw images are crossed by interference fringes. Therefore, these raw images do not look very sharp", explains Gerd Weigelt, a Professor at the Max-Planck-Institut für Radioastronomie in Bonn, Germany. "However, modern image reconstruction methods, so-called deconvolution, allow us to overcome the interference fringes and achieve a spectacular image resolution.”

"Data processing based on deconvolution methods", adds Mario Bertero, a professor in Information Science at the University of Genova (Italy), "are basic for detecting details not directly distinguishable in the interferometric images. However they can generate artifacts and, for this reason, it is important to process the images with different methods for discriminating between relevant details and artifacts.”

"While we have seen bright emissions – always one unresolved spot – “pop-up” at different locations in Loki Patera over the years”, explains Imke de Pater, a Professor at the University of California in Berkeley, "these exquisite images from the LBTI show for the first time in ground based images that emissions arise simultaneously from different sites in Loki Patera. This strongly suggests that the horseshoe-shaped feature is most likely an active overturning lava lake, as hypothesized in the past.”

"Two of the volcanic features are at newly-active locations", explains Katherine de Kleer, a graduate student at the University of California at Berkeley. "They are located in a region called the Colchis Regio, where an enormous eruption took place just a few months earlier, and may represent the aftermath of that eruption. The high resolution of the LBTI allows us to resolve the residual activity in this region into specific active sites, which could be lava flows or nearby eruptions."

"Studying the very dynamic volcanic activity on Io, which is constantly reshaping the moon's surface, provides clues to the interior structure and plumbing of this moon," remarked team member Chick Woodward of the University of Minnesota. "It helps to pave the way for future NASA missions such as the Io Observer. Io's highly elliptical orbit close to Jupiter is constantly tidally stressing the moon, like the squeezing of a ripe orange, where the juice can escape through cracks in the peel."

For Christian Veillet, Director of the Large Binocular Telescope Observatory (LBTO), "this study marks a very important milestone for the Observatory. The unique feature of the binocular design of the telescope, originally proposed more than 25 years ago, is its ability to provide images with the level of detail (resolution) only a single-aperture telescope at least 22.7m in diameter could reach. The spectacular observations of Io published today are a tribute to the many who believed in the LBT concept and worked very hard over more than two decades to reach this milestone."

Veillet adds: "While there is still much work ahead to make the LBT/LBTI combination a fully operational instrument, we can safely state that the Large Binocular Telescope is truly a forerunner of the next generation of Extremely Large Telescopes slated to see first light in a decade (or more) from now."


The Large Binocular Telescope (LBT) is an international collaboration among institutions in the U.S., Italy and Germany. LBT Corporation partners are: The University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; The Ohio State University, and The Research Corporation, on behalf of The University of Notre Dame, University of Minnesota and University of Virginia. The Large Binocular Telescope Interferometer is funded by NASA as part of its Exoplanet Exploration program. LMIRcam is funded by the National Science Foundation through grant NSF AST-0705296. The research was partially supported by the National Science Foundation, NSF Grant AST-1313485 to UC Berkeley, and by the National Science Foundation Graduate Research Fellowship under Grant DGE-1106400.

The research team is led by Albert Conrad from the LBT Observatory (University of Arizona). Besides the local members Karl-Heinz Hofmann, Dieter Schertl and Gerd Weigelt (all Max Planck Institute for Radio Astronomy, Bonn) it comprises Katherine de Kleer and Imke de Pater (both University of California at Berkeley), Jarron Leisenring, Denis Defrère, Philip Hinz and Andy Skemer (all University of Arizona), Andrea la Camera, Mario Bertero and Patricia Boccacci (all DIBRIS, University of Genua), Carmelo Arcidiacono (INAF, Osservatorio Astronomico di Bologna), Martin Kürster (Max Planck Institute for Astronomy, Heidelberg), Julie Rathbun (Planetary Science Institute, Tucson), Michael Skrutskie (University of Virginia), John Spencer (Southwest Research Institute, Boulder), Christian Veillet (LBT Observatory) and Charles E. Woodward (Minnesota Institute for Astrophysics).

Original Paper:

Spatially resolved M-band emission from Io's Loki patera - Fizeau imaging at the 22.8m LBT, Albert Conrad et al., 2015, Astronomical Journal:
http://iopscience.iop.org/1538-3881/149/5/175/article
doi: 10.1088/0004-6256/149/5/175

Local Contact:

Prof. Dr. Gerd Weigelt,
Max-Planck-Institut für Radioastronomie, Bonn.
Fon: +49-228-525-243
E-mail: gweigelt@mpifr-bonn.mpg.de

Dr. Karl-Heinz Hofmann
Max-Planck-Institut für Radioastronomie, Bonn.
Fon: +49-228-525-290
E-mail: khh@mpifr-bonn.mpg.de

Dr. Dieter Schertl
Max-Planck-Institut für Radioastronomie, Bonn.
Fon: +49-228-525-301
E-mail: dschertl@mpifr-bonn.mpg.de

Dr. Norbert Junkes,
Press and Public Outreach,
Max-Planck-Institut für Radioastronomie.
Fon: +49(0)228-525-399
E-mail: njunkes@mpifr-bonn.mpg.de

Weitere Informationen:

http://www.mpifr-bonn.mpg.de/pressreleases/2015/5

Norbert Junkes | Max-Planck-Institut für Radioastronomie

More articles from Physics and Astronomy:

nachricht First evidence on the source of extragalactic particles
13.07.2018 | Technische Universität München

nachricht Simpler interferometer can fine tune even the quickest pulses of light
12.07.2018 | University of Rochester

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Research finds new molecular structures in boron-based nanoclusters

13.07.2018 | Materials Sciences

Algae Have Land Genes

13.07.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>