Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tempel 1 is weak X-ray source, XMM-Newton confirms

06.07.2005


ESA’s XMM-Newton observations of Comet 9P/Tempel 1 revealed that the object is a weak X-ray source. These data were acquired on 4 July 2005 by one of the EPIC X-ray cameras on board the spacecraft during the post-impact observation phase.


Image recorded by EPIC instrument on XMM-Newton



XMM-Newton observed that Tempel 1 emits X-rays, as suspected from previous observations of comets, but this emission is very weak. It is not certain whether it is possible to obtain spectral data which indicate the mechanisms by which the comet’s X-rays are produced. Further analysis of the XMM-Newton data is needed to confirm this.

There are two theories to explain why comets emit X-rays. In the first theory, X-rays are produced by a charged exchange between neutral particles present in the comet’s coma and ionised particles carried by the solar wind. This has been demonstrated already for several comets in the past.


The second explanation is that the X-rays are just solar X-rays scattered by the dust present in the coma. This could happen during comet outbursts, as observations of Comet Hale-Bopp indicated in 1996. A combination of both mechanisms is also possible.

Even without the task of analysing these weak X-rays, observing the X-ray emission from moving objects like Tempel 1 is already a complex enough task for an X-ray telescope. In fact, XMM-Newton is best suited to studying ’fixed’ X-ray sources in the sky. Special planning and processing techniques were required to overcome this observational challenge.

During the observations, XMM-Newton was pointed in the direction of the comet as if it was fixed in the sky, and its instruments were exposed to the radiation (photons) coming from it.

The photons coming from the moving comet were received by the relatively stationary XMM-Newton instruments. Scientists used the arrival time and direction associated with each detected photon to deduce its distance from the comet’s nucleus.

Every photon was then ’transformed’ mathematically, as if it came from a ’virtual’ comet fixed in the sky like the more distant stars. In this way, scientists could treat the comet as a non-moving object.

Scientists then ’cleaned’ the data files, by removing those times where the cosmic background radiation was disturbing the observations.

Rita Schulz | EurekAlert!
Further information:
http://www.esrin.esa.int/esaCP/SEMXA46DIAE_index_0.html

More articles from Physics and Astronomy:

nachricht SF State astronomer searches for signs of life on Wolf 1061 exoplanet
20.01.2017 | San Francisco State University

nachricht Molecule flash mob
19.01.2017 | Technische Universität Wien

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: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>