. 24/7 Space News .
IRON AND ICE
Rosetta's intimate portrait of a comet: read all about it
by Staff Writers
Paris (ESA) Apr 07, 2017


The surface, imaged in magnificent detail by the OSIRIS scientific camera and the NavCam navigation camera, displayed a wide range of landforms, including smooth plains, steep cliffs and pits that measured 100 metres wide and deep. Visible in the pit walls were 'goose bumps' about 3 metres in diameter.

Rosetta's pioneering mission to explore a comet in unprecedented detail completed operations last year. As the science continues, members of the public, as well as scientists, can freely access hundreds of papers that reveal the comet's secrets. A special issue of Monthly Notices of the Royal Astronomical Society is the latest journal to provide this service.

On 30 September 2016, after a two-year orbital tour around comet 67P/Churyumov-Gerasimenko, ESA's Rosetta spacecraft completed the most exciting mission of cometary exploration ever undertaken.

Having delivered its small Philae lander to the comet's surface earlier in the mission, Rosetta ended its historic adventure with the 1.5 tonne spacecraft making an unprecedented touchdown on the comet's dark nucleus.

Before the intrepid explorer ceased transmitting, its 11 scientific instruments, together with the suite of instruments on board Philae, investigated every aspect of the comet's solid nucleus, its eruptive jets of gas and dust, and its interaction with interplanetary space. Data from the instruments have provided one surprise after another.

A wealth of discoveries

Even before Rosetta arrived at comet 67P/C-G on 6 August 2014, its cameras had revealed a rugged, double-lobed structure that was popularly compared to the shape of a rubber duck.

The surface, imaged in magnificent detail by the OSIRIS scientific camera and the NavCam navigation camera, displayed a wide range of landforms, including smooth plains, steep cliffs and pits that measured 100 metres wide and deep. Visible in the pit walls were 'goose bumps' about 3 metres in diameter.

To study the internal structure, the CONSERT experiment passed radio waves through the nucleus between the Philae lander and the orbiter. It showed that the 'head' of the comet is highly porous - consistent with a loosely compacted 'rubble pile' of dust and ice. Additional insight into the structure of the interior was provided by the Radio Science Investigation.

The Philae lander provided the 'ground truth' of the comet nucleus, revealing it to be devoid of a magnetic field, having a dusty surface with a harder, sintered subsurface, and a number of organic compounds and volatile molecules near the surface. The final resting place of Philae is a complex terrain, with fractures of varying scales and indications of ice deposits.

During Rosetta's approach to the comet in 2014, the MIRO instrument registered a 10-fold increase in the amount of water vapour being released by the comet over a period of only two months.

The characteristics of the comet's dust were pinned down by measurements from GIADA, COSIMA, and MIDAS. However, the ratio of dust to gas emitted by the nucleus showed that the comet is best described as an icy dust ball rather than a dirty snowball.

The VIRTIS instrument showed that, despite the icy composition of the nucleus, the surface was extremely dark as the result of a dusty coating. This was also the conclusion from observations made at far-ultraviolet wavelengths by the Alice instrument. Readings from the ROSINA instrument showed that the water making up the comet was substantially different from the water on Earth, indicating that our planet's oceans may not have been fed by incoming comets.

ROSINA also discovered over 60 molecules, 34 of which had never been found before on a comet. These included the first detection of carbon dioxide on a comet.

Other instruments, in particular those of the Rosetta Plasma Consortium, studied how the outflowing gas in the coma interacted with the solar wind - a stream of charged particles continuously flowing from the Sun.

Data received from Rosetta and Philae is already rewriting the text books. Indeed, so much information was returned from the mission that it will take researchers many years to analyse it.

Sharing the scientific harvest
Matt Taylor, ESA's Rosetta Project Scientist, has been working with the international science teams in an effort to make their results available as quickly as possible to the wider community.

This has been made easier since the operational phase of the mission is over, because the teams can now focus on the mass of scientific data returned by Rosetta.

The teams have also been striving to have the scientific papers made available to the general public, as much as possible, through free access publications.

As a result, hundreds of articles and reports, based on the treasure trove of data returned by Rosetta and Philae, are now freely available to anyone who wants to discover the results of this pioneering mission to explore a comet.

Two special issues of the prestigious journal Science, published in January and July 2015, have been devoted to early results from Rosetta and Philae. They were followed by a special issue of Astronomy and Astrophysics that covered Rosetta results pre-perihelion, building on the Science special issues by providing more in-depth analysis.

The latest free access publication is a special issue of Monthly Notices of the Royal Astronomical Society (MNRAS) - based on the ESLAB meeting held in Leiden (The Netherlands) in March 2016. This issue, which is now complete and available online, can be accessed here.

The ESLAB meeting focused on the 30th anniversary of ESA's Giotto mission to Halley's comet, and how subsequent missions such as Rosetta have changed our ideas of cometary science since Giotto. The Rosetta results discussed at the meeting (and contained in the special issue) represent another milestone in the evolution of cometary science, as scientists begin to analyse data obtained at perihelion and beyond, with some initial conclusions on the evolution of cometary activity.

Another MNRAS special issue will be published later this year, based on a special end of mission symposium held in Toulouse in November 2016. That meeting focused on looking at how Rosetta and Philae have changed our understanding of comets.

Papers within that special issue will provide the next milestone in the evolution of Rosetta science by considering the entire two-year period of comet exploration.

Looking further ahead, mission scientists will discuss the next block of results to be published, perhaps aiming to concentrate on more specific topics. For example, a science conference is being planned in Sofia, Bulgaria, this year to focus on how comets form.

"The core focus of activity from the ESA point of view, now operations are over, is the archiving of the data, an activity driven from the European Space Astronomy Centre in Spain, with guidance from project scientists at ESA and NASA," said Matt Taylor.

"Instrument teams are working hard to deliver all the data and together we are looking at building the best legacy for Rosetta, so that scientific analysis will continue for decades to come.

"We are now in the core scientific phase, digging ever deeper into the data, so there will be many more surprises and insights into comets and the evolution of our Solar System over the coming years."

IRON AND ICE
Comet That Took a Century to Confirm Passes by Earth
Greenbelt MD (SPX) Apr 03, 2017
On April 1, 2017, comet 41P will pass closer than it normally does to Earth, giving observers with binoculars or a telescope a special viewing opportunity. Comet hunters in the Northern Hemisphere should look for it near the constellations Draco and Ursa Major, which the Big Dipper is part of. Whether a comet will put on a good show for observers is notoriously difficult to predict, but 41 ... read more

Related Links
Rosetta at ESA
Asteroid and Comet Mission News, Science and Technology


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only


Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

IRON AND ICE
NASA Invests in 22 Visionary Exploration Concepts

Two Russians, one American land back on Earth from ISS

US, Russian Astronauts Prepare for April Crew Swap on Space Station

No Roscosmos plans to send space tourists to ISS before 2020

IRON AND ICE
Dream Chaser to use Europe's next-generation docking system

Bezos sells $1 bn in Amazon stock yearly to pay for rocket firm

Europe's largest sounding rocket launched from Esrange

US-Russia Venture Hopes to Sell More RD-180 Rocket Engines to US

IRON AND ICE
Russia critcal to ExoMars Project says Italian Space Agency Head

Chile desert combed for clues to life on Mars

New MAVEN findings reveal how Mars' atmosphere was lost to space

Potential Mars Airplane Resumes Flight

IRON AND ICE
Yuanwang fleet to carry out 19 space tracking tasks in 2017

China Develops Spaceship Capable of Moon Landing

Long March-7 Y2 ready for launch of China's first cargo spacecraft

China Seeks Space Rockets Launched from Airplanes

IRON AND ICE
Ukraine in talks with ESA to become member

Horizon 2020 European funded DEMOCRITOS project concludes work with some key outcomes

Russian Satellite Builder Reshetnev Fully Switches to Import Substitution

BRICS States Want to Expand Cooperation to Space Science

IRON AND ICE
DARPA Wades into Murky Multimedia Information Streams to Catch Big Meaning

New research could help speed up the 3-D printing process

Spray-on memory could enable bendable digital storage

European conference on space debris risks and mitigation

IRON AND ICE
'Smart' cephalopods trade off genome evolution for prolific RNA editing

Atmosphere around super-earth detected

Scientists look for life's building blocks in outer space

Possible Venus twin discovered around dim star

IRON AND ICE
Hubble takes close-up portrait of Jupiter

When Jovian Light and Dark Collide

Neptune's journey during early planet formation was 'smooth and calm'

Neptune's movement from the inner to the outer solar system was smooth and calm









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.