On Thursday evening, at the time of its closest approach to the sun, comet ISON still had an active nucleus which was spewing gas and dust. About two hours after the Perihelion passage, however, there were no longer indications for any output.
The remains of ISON: On this image taken by satellite Soho, a tail-like structure is moving away from the sun. But now the comet is fading.
© ESA / NASA / SOHO
This is the assessment made by scientists at the Max Planck Institute for Solar System Research in Katlenburg- Lindau on Saturday. They analysed actual pictures of the instrument LASCO which enjoys a unique view of the comet from its vantage point on board of the Solar Observatory SOHO.
On current photographs, the brightness of the apparently inactive comet is gradually decreasing. It is almost certain that there won't be a spectacular comet display after all.
Against 8:30 p.m. yesterday evening, the tail of ISON emerged from behind sun in the field of view of the LASCO instrument. At this point in time, however, it was unclear whether the tip of the tail concealed a nucleus or not. Pictures taken a few hours after Perhelion now allow further conclusions to be drawn.
"The dust tail of the comet is now divided into two parts," explains Hermann Böhnhardt from the Max Planck Institute for Solar System Research. According to Böhnhardt, the part of the tail that is pointing towards the sun consists of dust particles, which were released significantly before the comet's Perihelion passage – i.e. prior to reaching the closest point to the sun.
The other part, however, appears to contain more recent material: It was released when ISON passed the sun and suggests that at least part of the nucleus still existed and was active at that time.
The Max Planck researchers base their assessment on computer simulations in which they model the shape of the dust tail. "If we assume in our calculations that the comet has emitted dust at Perihelion, we can reproduce the current images quite well," says Böhnhardt.
The LASCO images from Saturday showed the ISON stopped producing dust two hours after Perhelion. Whether the comet nucleus was still intact at Perihelion or continued its flight as a small fragment or as collection of chunks is not yet clear.
The instrument Sumer on board of the satellite SOHO, which was developed and built under the auspices of the Max Planck Institute in Lindau observed ISON on Thursday night in the hour when it directly approached the sun. The instrument divides the light that is sent into space by the celestial body into its individual components. From this, researchers can draw conclusions about the elements and molecules in the comet's dust cloud.
"Our measurements show a clear signal of the comet during its flight past the sun," says Max Planck scientist Werner Curdt. Exact results of the measurement, however, are not yet available.
ContactDr. Birgit Krummheuer
Dr. Birgit Krummheuer | Max-Planck-Institute
Further Improvement of Qubit Lifetime for Quantum Computers
09.12.2016 | Forschungszentrum Jülich
Electron highway inside crystal
09.12.2016 | Julius-Maximilians-Universität Würzburg
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
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:...
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...
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...
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...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine