Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

X-ray emission from Saturn

08.03.2004


X-ray image of Saturn (in false colour)
Credit: Astronomy & Astrophysics


The Chandra X-ray Observatory is a space observatory dedicated to X-ray astronomy. Launched on July 23rd, 1999, this X-ray telescope is particularly dedicated to the observation of high-energy sources in the universe. It has also been used to study the following solar system objects: the Moon, Venus, Mars, Jupiter, and even the Comet C/1999 S4 LINEAR.

Using Chandra, J.-U. Ness and his colleagues detected an unambiguous X-ray emission from the planet Saturn for the first time. A few years ago, a possible such emission was observed using ROSAT, but the present detection is the first certain one.

Ness and his team observed Saturn in April 2003 for about 20 hours. The picture below shows the X-ray image of Saturn that they obtained (in false colour). Each colour (RGB) corresponds to a different energy range of the observed X-rays. Beyond the X-ray detection from Saturn, this Chandra observation allowed the investigators to perform the first in-depth analysis of this emission. The same team also detected X-ray emissions from Saturn using the XMM-Newton Observatory. The observed signal was very similar to what was found with Chandra.



Besides Saturn, other bodies of the solar system, such as the Earth, the Moon, Venus, Mars, Jupiter, comets, and Galilean satellites, emit X-rays. Depending upon the body, these emissions originate from different physical processes. One of the major processes occurs when these bodies scatter the solar X-rays produced by the hot, tenuous solar corona. For all terrestrial bodies that emit X-rays - that is, the Earth, the Moon, and Venus - this mechanism is the main production process of X-rays.

Spectral analysis of the X-rays detected from Saturn with Chandra shows that the signal looks remarkably like that of solar X-ray emissions. This indicates that Saturn’s X-ray emission originates from solar X-rays scattering in Saturn’s atmosphere, a result that is very surprising, as such a process has already been studied on the Moon and was not expected to be so efficient on Saturn.

In addition to the scattering of solar X-rays, on Earth, X-rays are also produced by the same mechanism that creates the aurorae in the polar regions. Aurorae are caused by solar wind electrons that enter the Earth’s atmosphere, thus resulting in these spectacular visible lights. At the same time, X-rays are also produced. The same mechanism has been found to exist on Jupiter: Jovian aurorae have been detected in the UV wavelengths, along with an associated X-ray emission. Saturn was also expected to emit X-rays in the polar region, since spectacular polar aurorae have been observed in the UV wavelengths.

With Chandra, J.-U. Ness and his colleagues were able to study for the very first time how the X-rays are distributed on Saturn’s disk, in order to look for polar X-ray emission. They found that the observed X-ray emission appears to be concentrated around Saturn’s equator. Surprisingly, no auroral X-ray emission has been observed at all. However, the North Pole was occulted by Saturn’s rings and X-ray emission from northern polar regions may have been hidden.

Comparison between Saturn’s and Jupiter’s X-ray emissions shows that their X-ray production mechanisms are very different. First of all, the spatial distribution differs: on Jupiter, X-rays are concentrated in polar regions, suggesting that magnetic fields play an important role. Such a polar X-ray emission has not been found on Saturn, but cannot be excluded. Secondly, the X-ray flux on Saturn is significantly lower than that seen on Jupiter. Nonetheless, the emission level observed from Saturn is consistent with the X-ray equatorial emission from Jupiter, indicating that both emissions originate from similar processes. Ness and his colleagues point out that no single mechanism can easily account for the observed emissions; therefore, they expect combined mechanisms to be involved.

Thanks to the high-angular resolution of the Chandra Observatory, the new detection of X-ray emissions from Saturn, as well as recent results on the same subject from Jupiter, will allow for important progress in the observations of X-rays on giant planets.

Jennifer Martin | Astronomy & Astrophysics
Further information:
http://www.edpsciences.org/papers/aa/pdf/press-releases/PR20030736.html

More articles from Physics and Astronomy:

nachricht Significantly more productivity in USP lasers
06.12.2016 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Shape matters when light meets atom
05.12.2016 | Centre for Quantum Technologies at the National University of Singapore

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: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>