Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Hubble captures outburst from comet targeted by Deep Impact

27.06.2005


In a dress rehearsal for the rendezvous between NASA’s Deep Impact spacecraft and comet 9P/Tempel 1, the Hubble Space Telescope captured dramatic images of a new jet of dust streaming from the icy comet.


In a dress rehearsal for the rendezvous between NASA’s Deep Impact spacecraft and comet 9P/Tempel 1, the Hubble Space Telescope captured dramatic images of a new jet of dust streaming from the icy comet. The images are a reminder that Tempel 1’s icy nucleus, roughly the size of central Paris, is dynamic and volatile. Astronomers hope the eruption of dust seen in these observations is a preview of the fireworks that may come 4 July, when a probe from the Deep Impact spacecraft will slam into the comet, possibly blasting off material and giving rise to a similar dust plume.



The images are a reminder that Tempel 1’s icy nucleus, roughly the size of central Paris, is dynamic and volatile. Astronomers hope the eruption of dust seen in these observations is a preview of the fireworks that may come 4 July, when a probe from the Deep Impact spacecraft will slam into the comet, possibly blasting off material and giving rise to a similar dust plume.

These observations demonstrate that Hubble’s sharp "eye" can see exquisite details of the comet’s temperamental activities. The Earth-orbiting observatory was 120 million kilometres away from the comet when these images were taken by the Advanced Camera for Surveys’ High Resolution Camera. The telescope’s views complement close-up images being taken by cameras aboard Deep Impact, which is speeding toward the comet.


The two images, taken seven hours apart on 14 June, show Tempel 1 and its new jet. The image at left, taken at 7:17 a.m. (UT), is a view of the comet before the outburst. The bright dot is light reflecting from the comet’s nucleus, which appears star-like in these images because it is too small even for Hubble to resolve. The nucleus, a potato-shaped object, is 7 kilometres across and 2 kilometres long. Hubble’s viewing the nucleus is as difficult as someone trying to spot a potato in Stockholm from Madrid.

The photo at right, snapped at 14:15 a.m. (UT), reveals the jet [the bright fan-shaped area]. The jet extends about 2,200 kilometers, which is roughly the distance from Copenhagen to Athens. It is pointing in the direction of the Sun. Comets frequently show outbursts in activity, but astronomers still don’t know exactly why they occur. Tempel 1 has been moving closer to the Sun, and perhaps the increasing heat opened up a crack in the comet’s dark, crusty surface. Dust and gas trapped beneath the surface could then spew out of the crack, forming a jet. Or, perhaps a portion of the crust itself was lifted off the nucleus by the pressure of heated gases beneath the surface. This porous crust might then crumble into small dust particles shortly after leaving the nucleus, producing a fan-shaped coma on the sunward side. Whatever the cause, the new feature may not last for long.

Astronomers hope that the July 4 collision will unleash more primordial material trapped inside the comet, which formed billions of years ago. Comets are thought to be ‘dirty snowballs’, porous agglomerates of ice and rock that dwell in the frigid outer boundaries of our solar system. Periodically, they make their journey into the inner solar system as they loop around the Sun.

The contrast in these images has been enhanced to highlight the brightness of the new jet.

In Europe, the European Southern Observatory will conduct a massive ground-based observing campaign before and in the week after the impact.

Lars Christensen | alfa
Further information:
http://www.spacetelescope.org
http://www.eso.org

More articles from Physics and Astronomy:

nachricht Creative use of noise brings bio-inspired electronic improvement
26.09.2017 | American Institute of Physics

nachricht The fastest light-driven current source
26.09.2017 | Friedrich-Alexander-Universität Erlangen-Nürnberg

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: The fastest light-driven current source

Controlling electronic current is essential to modern electronics, as data and signals are transferred by streams of electrons which are controlled at high speed. Demands on transmission speeds are also increasing as technology develops. Scientists from the Chair of Laser Physics and the Chair of Applied Physics at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have succeeded in switching on a current with a desired direction in graphene using a single laser pulse within a femtosecond ¬¬ – a femtosecond corresponds to the millionth part of a billionth of a second. This is more than a thousand times faster compared to the most efficient transistors today.

Graphene is up to the job

Im Focus: LaserTAB: More efficient and precise contacts thanks to human-robot collaboration

At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.

Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Fraunhofer ISE Pushes World Record for Multicrystalline Silicon Solar Cells to 22.3 Percent

25.09.2017 | Power and Electrical Engineering

Usher syndrome: Gene therapy restores hearing and balance

25.09.2017 | Health and Medicine

An international team of physicists a coherent amplification effect in laser excited dielectrics

25.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>