Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cassini’s Radar And Vims Instruments Eye Impact Crater On Titan

28.04.2005


The Cassini spacecraft has seen a 50-mile-diameter impact crater on Titan with different instruments on separate flybys, giving scientists new information on impact-crater formation on Saturn’s giant moon.

They’ve released a composite image of one of Titan’s most prominent impact craters as previously seen by Cassini’s radar and recently seen by its Visual and Infrared Mapping Spectrometer (VIMS).

The composite image is online at saturn.jpl.nasa.gov and at uanews.org.



The radar image was taken during the Cassini spacecraft’s Feb. 15, 2005 Titan flyby, and the VIMS images were taken during its April 16, 2005 Titan flyby, said Robert H. Brown of The University of Arizona, head of the VIMS experiment. Brown released the composite image at the European Geosciences Union meeting in Vienna, Austria, on Monday (April 25).

In radar, the crater and its ejecta blanket are bright. In radar, brighter surfaces mean rougher terrains, or else terrains tilted towards the radar. At VIMS infrared wavelengths, the crater appears dark and the ejecta blanket is bright, showing that the crust on the crater floor is different material than the ejecta.

"The composite image highlights the differences and similarities in how two instruments see the same thing," Brown said. "It shows the power of combining instruments when you are trying to understand objects in the Saturnian system."

VIMS is essentially a camera that takes pictures in 352 different colors at the same time. The colors cover the visible spectrum and into the infrared, or from three-tenths of a micron up to five and one-tenth microns. (A micron is one millionth of a meter.) Scientists can identify the chemical composition of the surfaces, atmospheres and rings of Saturn and its moons using VIMS.

Cassini began a 4-year-or-more exploratory tour of the Saturn system in July 2004. It has seen two impact craters on Titan so far.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The radar instrument team is based at JPL, working with team members from the United States and several European countries. The visual and infrared mapping spectrometer team is based at the University of Arizona, Tucson.

This three-panel image shows one of Titan¹s most prominent impact craters in an infrared-wavelength image (left), radar image (center) and in the false-color image (right). The Cassini radar imaged this crater during Cassini¹s third flyby of Titan, on Feb. 15, 2005, (see PIA07368). The crater, located at 16 degrees west, 11 degrees north, is about 80 kilometers (50 miles) in diameter and is surrounded beyond that by a blanket of material thrown out of the crater during impact. In radar, brighter surfaces mean rougher terrains, or else terrains tilted toward the radar.

Two Titan flybys later, on April 16, the visual infrared mapping spectrometer on Cassini obtained images of the same crater. The panel on the left is an image at the 2.0 micron wavelength, showing that the crater has a dark floor and a small bright area in the center. The crater is surrounded by bright material, which has a very faint halo slightly darker than the surrounding dark material. Compare the radar image with the visual infrared mapping spectrometer image. Both the crater and the blanket of surrounding material (called ejecta) are bright at radar wavelengths; in the infrared, the crater itself is dark and this blanket of material is quite bright. In radar, the faint halo surrounding the blanket of material is quite similar in appearance to the rest of the ejecta blanket.

The right hand panel is a false-color visual infrared mapping spectrometer image of the crater at lower resolution. It shows the faint halo to be slightly bluer than surrounding material. That the material is bluer than its surroundings, while also being darker, suggests that the faint halo is somewhat different in composition. This suggests that the composition of Titan¹s upper crust varies with depth, and various materials were excavated when the crater was formed.

The same structure appearing so different to different instruments illustrates the importance of multiple instruments studying such phenomena. The Cassini spacecraft, being the most interdisciplinary spacecraft ever flown, strongly embodies such an approach.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The radar instrument team is based at JPL, working with team members from the United States and several European countries. The visual and infrared mapping spectrometer team is based at the University of Arizona, Tucson.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. For more information about the visual and infrared mapping spectrometer visit http://wwwvims.lpl.arizona.edu/. Credit: NASA/JPL/University of Arizona

Lori Stiles | UA News Services
Further information:
http://www.arizona.edu

More articles from Physics and Astronomy:

nachricht Writing and deleting magnets with lasers
19.04.2018 | Helmholtz-Zentrum Dresden-Rossendorf

nachricht Ultrafast electron oscillation and dephasing monitored by attosecond light source
19.04.2018 | Yokohama National University

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: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

Im Focus: The Future of Ultrafast Solid-State Physics

In an article that appears in the journal “Review of Modern Physics”, researchers at the Laboratory for Attosecond Physics (LAP) assess the current state of the field of ultrafast physics and consider its implications for future technologies.

Physicists can now control light in both time and space with hitherto unimagined precision. This is particularly true for the ability to generate ultrashort...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Diamond-like carbon is formed differently to what was believed -- machine learning enables development of new model

19.04.2018 | Materials Sciences

Electromagnetic wizardry: Wireless power transfer enhanced by backward signal

19.04.2018 | Physics and Astronomy

Ultrafast electron oscillation and dephasing monitored by attosecond light source

19.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>