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  • richardmitnick 10:09 am on August 13, 2015 Permalink | Reply
    Tags: , , Comets,   

    From SPACE.com: “Comet and Rosetta Spacecraft Make Closest Approach to the Sun” 

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    SPACE.com

    August 13, 2015
    Elizabeth Howell

    Temp 1

    After more than a year in orbit around a comet, the European Rosetta spacecraft and its icy dance partner are hitting a huge milestone: their closest approach to the sun.

    ESA Rosetta spacecraft
    Rosetta

    The Rosetta and its target, Comet 67P/Churyumov–Gerasimenko, reach perihelion today (Aug. 13), when the comet’s 6.5-year orbit brings it within 114.9 million miles (185 million kilometers) of the sun.

    Activity is already exploding on Comet 67P. In late July, Rosetta’s camera caught a jet erupting in the space of less than half an hour. And because it takes about a month for the comet to get its warmest, this means that activity is expected to peak in a few short weeks.

    2

    “The key to the Rosetta mission is that it is there for the long haul. It is there to watch and observe changes in the comet over time, with the same suite of instruments, as opposed to a flyby — or maybe different missions having flybys at different times with different instruments,” said Joel Parker, an interdisciplinary scientist on the mission. He is a research astronomer and director at the Southwest Research Institute in San Antonio, Texas.

    Rosetta arrived in orbit around Comet 67P on Aug. 6, 2014, nearly 10 years after launching into space. In November of last year, the orbiter’s small Philae lander touched down on the comet to study the object’s surface.

    “This is creating the baselines for all future study of comet activity for us to understand what is going on at the small scale, that cannot be observed from Earth or near-Earth observations,” Parker told Space.com.

    Among other things, researchers will learn about how the brightness of a comet increases, which could lead to better predictions for amateur astronomers, he said. Researchers will also look at how the composition of the comet’s emissions (dust and gas) change, which will provide clues about what the early universe looked like.

    How the solar system was

    Comets such as 67P are considered chunks of what the solar system appeared to be early in its formation, before the planets and moons were formed. Studying comets and asteroids therefore helps researchers understand the makeup of the young solar system shortly after its formation 4.5 billion years ago.

    Rosetta is the first spacecraft to orbit a comet and also the first to drop a small probe, the Philae comet lander, on a comet’s surface. Among other findings, the Rosetta mission revealed that the type of water on the comet is different than that of Earth, meaning that comets like 67P could not have delivered water to this planet. The spacecraft also detected organics, a building block to life on Earth, and possibly across the universe.

    There has been some discussion (and dispute) among the Rosetta researchers as to whether the comet’s outgassing will change as the object gets closer to the sun, said Paul Weissman, another Rosetta interdisciplinary scientist who recently retired from NASA’s Jet Propulsion Laboratory in California.

    Solar heating could unveil deeper regions of the comet that were untouched for millions or billions of years, depending on how much bled away when 67P passed by the sun previously.

    “This comet has this unusual … ratio” of the constituents of hydrogen in water, specifically the ratio of a rarer type of hydrogen, called deuterium, to hydrogen, Weissman said. “We’re curious to see if that changes as it goes around the sun and as it gets more active.

    Comet brightness

    It is notoriously difficult for even professional astronomers to predict how bright a comet will appear when it swings by Earth. This is because it’s difficult to see the nucleus (heart) of the comet, Parker said, so measurements are made from observing the comet or atmosphere.

    As Rosetta observes 67P from up close, the spacecraft will see how much gas is coming out, what dust the gas is dragging out and how big the gas particles are, Parker said. Weissman added that these particles could be a centimeter (0.4 inches) across or larger, which is big enough for the comet’s imaging instruments to resolve the individual particles and potentially, track their movements.

    The team will also be observing how the solar wind, the constant stream of gas from the sun, interacts with the comet’s surface and causes changes, Weissman said. The researchers will additionally watch how the coma of the comet – the dusty envelope around its nucleus – flexes when the solar wind hits it.

    Rosetta’s current mission ends on Sept. 30, 2016, when the mission will be operating at about four astronomical units or AU from Earth. (One astronomical unit is the Earth-sun distance, about 93 million miles or 150 million km.) At that point, the spacecraft will be so far from the sun that it will be difficult for its solar panels to collect the energy required to continue operating, so further work after that is unlikely, Weissman said.

    See the full article here.

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  • richardmitnick 3:19 pm on July 13, 2015 Permalink | Reply
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    From ESA: “Rosetta: preparing for perihelion” 

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    European Space Agency

    13 July 2015
    No Writer Credit

    ESA Rosetta spacecraft
    Rosetta with Philae

    1
    Comet around perihelion

    Rosetta’s investigations of its comet are continuing as the mission teams count down the last month to perihelion – the closest point to the Sun along the comet’s orbit – when the comet’s activity is expected to be at its highest.

    Rosetta has been studying Comet 67P/Churyumov–Gerasimenko for over a year now, with observations beginning during the approach to the comet in March 2014. This included witnessing an outburst in late April 2014 and the revelation of the comet’s curious shape in early July.

    After arriving at a distance of 100 km from the double-lobed comet on 6 August, Rosetta has spent an intense year analysing the properties of this intriguing body – the interior, surface and surrounding dust, gas and plasma.

    Comets are known to be made of dust and frozen ices. As these ices are warmed by the Sun, they turn directly to vapour, with the gases dragging the comet’s dust along with it. Together, the gas and dust create a fuzzy atmosphere, or coma, and often-spectacular tails extend tens or hundreds of thousands of kilometres into space.

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    Comet on 25 June 2015 – NavCam

    While ground-based observations can monitor the development of the coma and tail from afar, Rosetta has a ringside seat for studying the source of this activity directly from the nucleus. One important aspect of Rosetta’s long-term study is watching how the activity waxes and wanes along the comet’s orbit.

    The comet has a 6.5 year commute around the Sun from just beyond the orbit of Jupiter at its furthest, to between the orbits of Earth and Mars at it closest.

    Rosetta rendezvoused with the comet around 540 million km from the Sun. Today, 13 July, a month from perihelion, this distance is much smaller: 195 million km. Currently travelling at around 120 000 km/h around their orbit, Rosetta and the comet will be 186 million km from the Sun by 13 August.

    “Perihelion is an important milestone in any comet’s calendar, and even more so for the Rosetta mission because this will be the first time a spacecraft has been following a comet from close quarters as it moves through this phase of its journey around the Solar System,” notes Matt Taylor, ESA’s Rosetta project scientist.

    “We’re looking forward to reaching perihelion, after which we’ll be continuing to monitor how the comet’s nucleus, activity and plasma environment changes in the year after, as part of our long-term studies.”

    See our FAQ below for more on what can you expect from perihelion and the activities planned around it.

    ————————————————————————-

    Perihelion basics

    4
    Comet’s orbit

    What is perihelion exactly?
    Perihelion is the closest point a Solar System object gets to the Sun along its orbit (aphelion is the term given to the most distant point). The term derives from ancient Greek, where ‘peri’ means near and ‘helios’ means Sun.

    How close to the Sun will the comet be at perihelion?
    Comet 67P/Churyumov–Gerasimenko is on a 6.5 year elliptical orbit around the Sun which takes it between 850 million km (5.68 AU) from the Sun at its most distant, just beyond the orbit of Jupiter, and 186 million km (1.24 AU) at its nearest, between the orbits of Earth and Mars. As a comparison, Earth orbits the Sun at an average distance of 149 million km (1 Astronomical Unit, or AU). .

    At what moment does perihelion occur?
    For this comet, the upcoming perihelion occurs at 02:03 GMT on 13 August 2015. The previous perihelion took place on 28 February 2009.

    The comet during perihelion

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    Comet activity 31 January – 25 March 2015

    What happens to the comet during perihelion? Will there be a big difference in activity in the coming weeks?
    The comet’s activity has been growing over the last year that Rosetta has been at the comet. This is an incremental process brought about by the increase in solar energy incident on the comet, warming up its frozen ices that subsequently sublimate. Rosetta has been witnessing this gradual rise, and scientists expect that this activity will reach a peak during August and September. Outbursts are possible, but unpredictable.

    Other comets plunge into the Sun at perihelion, what about this one?
    Comet 67P/Churyumov–Gerasimenko does not get close enough to the Sun to be destroyed by it; its closest point is actually further than Earth ever gets to the Sun and, furthermore, the comet has survived many previous orbits. It is not, for example, classed as a ‘sungrazer’ like Comet C/2012 S1 ISON, which broke apart during its perihelion passage in November 2013.

    Will Comet 67P/C-G break apart during perihelion?
    The comet has not broken apart during its many previous orbits, so it is not expected to do so this time, but it cannot be ruled out. Scientists are keen to watch the possible evolution of a 500 m-long fracture that runs along the surface of the neck on the comet during the peak activity.

    What happens to the comet after perihelion?
    As with the last observed perihelia, we expect the comet to continue on its orbit as normal, away from the Sun and back towards the outer Solar System again. Thanks to the heat absorbed during perihelion, the activity is expected to remain high for a couple of months before gently decreasing towards the moderate activity levels seen earlier in the mission, allowing Rosetta to get closer to the nucleus again.

    Rosetta and Philae during perihelion

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    Rosetta approaching comet

    Does Rosetta have to do any special manoeuvres for perihelion?
    Perihelion is a very different milestone to the other events such as waking up from hibernation, arriving at or landing on the comet where critical operations had to be carried out. Perihelion is simply a moment in time, and in terms of operations, it is business as usual – no special manoeuvres are required. The mission team hopes to have Rosetta as close as possible to the comet during perihelion to perform science observations without jeopardising the safety of the spacecraft, but this distance is currently decided on a twice-weekly basis for the week ahead, so the exact distance for perihelion is not currently known. During the last few months, it has not been possible to operate closer than 150 km without running into difficulties caused by the vast amounts of dust around the comet at the present time.

    Are there any special science observations that will be done at the time of perihelion?
    As with operations, it is also business as usual for science observations – monitoring of the comet and its dust, gas and plasma environment will continue during perihelion. Scientists are particularly keen to study the southern hemisphere of the comet, which has been in full sunlight only since May.

    How long will it take Rosetta to communicate with Earth on 13 August?
    The one-way signal travel time on 13 August is 14 min 44 sec.

    When will we see an image from the moment of perihelion?
    Rosetta’s Navigation Camera takes images several times during each 24 hour Earth day for navigation purposes, while the science camera OSIRIS has dedicated imaging slots. While the imaging schedule is not currently known for perihelion, we are hoping to be able to share both NavCam and OSIRIS image(s) with you from around the time of perihelion, during the afternoon of 13 August. Note that for OSIRIS this will depend on the data prioritisation on that day and the time it takes to downlink so this cannot be guaranteed. Time is also needed to check and process the images for release (for both NavCam and OSIRIS). We will update this section if/when more information about the timing of the image release(s) is known.

    Will Rosetta and Philae be safe during perihelion?
    Owing to the large amounts of dust, Rosetta will continue to operate at a safe distance from the comet throughout perihelion. We cannot predict any sudden increases in activity of the comet in advance, but the spacecraft safety remains – as always – a priority.

    Philae is on the surface of the comet, although its exact location remains unknown. Having regained communications with Rosetta on 13 June the link has been unpredictable and intermittent. The mission teams are carefully analysing the situation and hope that Philae will be operational during perihelion (separate updates on Philae’s condition will be made via the Rosetta Blog).

    What will happen to the mission after perihelion?
    Rosetta will continue to follow the comet as it moves back towards the outer Solar System, watching how the activity decreases over time and monitoring any post-perihelion changes that may occur. The Rosetta mission is scheduled to continue until September 2016, when the nominal planning would see Rosetta spiral down to the surface of the comet, where operations would likely end.

    8
    Comet from Earth – 22 May 2015

    Observing the comet from Earth during perihelion

    Why is perihelion interesting for astronomers?
    Near perihelion, comets reach their highest level of brightness, releasing large amounts of gas and dust. Possible outbursts and other unpredictable events might also take place around perihelion, so it is extremely important to obtain as many observations as possible during this period. While ground-based observations provide large-scale context for Rosetta’s measurements, Rosetta’s close-up data provide in turn the possibility to calibrate many of the observations made from the ground. This unique opportunity will also improve the study and interpretation of ground-based observations of other comets.

    How close to Earth will the comet be at perihelion? Is this the closest it gets to Earth?
    While the distance between the comet and the Sun decreases steadily until perihelion, before increasing again afterwards up to aphelion, the distance between Earth and the comet depends on their relative positions in the Solar System. At perihelion, the comet is 265 million km from Earth, but it will be closer (222 million km) during January–February 2016. Follow the positions of Rosetta and the comet through the Solar System using our Where is Rosetta? tool.

    Will astronomers be observing the comet at perihelion?
    Yes, a large network of professional and amateur astronomers has been observing the comet from across the globe in the past months. Observations with professional telescopes are planned every night around perihelion, relying on several robotic telescopes in many locations, and spectroscopic observations will be performed once a week. More details of the professional campaign are available here.

    How can I observe the comet at perihelion?
    Unfortunately, even at perihelion, the comet is too faint to be seen with the naked eye. To observe the comet, you will need a good telescope: a minimum of a 20 cm-aperture telescope is recommended. Guidance on how amateur astronomers can observe the comet is available here How can I observe the comet at perihelion?
    Unfortunately, even at perihelion, the comet is too faint to be seen with the naked eye. To observe the comet, you will need a good telescope: a minimum of a 20 cm-aperture telescope is recommended. Guidance on how amateur astronomers can observe the comet is available here.

    Until when is it possible to observe the comet from Earth?
    The comet is currently passing from the southern sky to the northern sky, so its visibility depends on where you live. Around the time of perihelion, it can be observed from Earth in the early morning hours, just before sunrise. It will remain relatively close to the Sun in the sky, and thus observable in the early morning, for several months. Then, the comet will be in the night sky between December 2015 and March 2016, which will be the prime time for ground-based observations. By the middle of 2016 it will likely be too faint to see except by large telescopes owing to its distance from the Sun and Earth, and it will also start moving behind the Sun as seen from Earth.

    Media

    Will there be any special events to mark the occasion of perihelion?
    Members of the public and media are invited to join an online Google+ Hangout on 13 August, during which we hope to have one or more images on the ground from around the time of perihelion. Time and guests to be announced nearer the time.

    How can I follow online?
    You can follow the mission in a number of ways (see esa.int/rosetta for an overview). On Twitter, official updates will be made by @ESA_Rosetta using the hashtag #perihelion2015. Information will also be provided by the Rosetta blog and on the Rosetta Mission Facebook page. The image(s) from perihelion will be published on our main ESA web portal, esa.int, in an official press release. The Google+ Hangout will also be advertised on esa.int and will be available to watch live via ESA’s G+ page and later as a replay on G+ and ESA’s YouTube channel.

    See the full article here.

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    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 10:33 am on June 2, 2015 Permalink | Reply
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    From ESA: “Ultraviolet study reveals surprises in comet coma” 

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    European Space Agency

    For more information, please contact:

    Markus Bauer







    ESA Science and Robotic Exploration Communication Officer








    Tel: +31 71 565 6799








    Mob: +31 61 594 3 954








    Email: markus.bauer@esa.int

    Paul Feldman
    Johns Hopkins University, Baltimore
    Email: pfeldman@jhu.edu

    Matt Taylor






    ESA Rosetta project scientist






    Email: matthew.taylor@esa.int

    Rosetta’s continued close study of Comet 67P/Churyumov–Gerasimenko has revealed an unexpected process at work, causing the rapid breakup of water and carbon dioxide molecules spewing from the comet’s surface.

    ESA Rosetta spacecraft
    Rosetta

    ESA’s Rosetta mission arrived at the comet in August last year. Since then, it has been orbiting or flying past the comet at distances from as far as several hundred kilometres down to as little as 8 km. While doing so, it has been collecting data on every aspect of the comet’s environment with its suite of 11 science instruments.

    One instrument, the Alice spectrograph provided by NASA, has been examining the chemical composition of the comet’s atmosphere, or coma, at far-ultraviolet wavelengths.

    At these wavelengths, Alice allows scientists to detect some of the most abundant elements in the Universe such as hydrogen, oxygen, carbon and nitrogen. The spectrograph splits the comet’s light into its various colours – its spectrum – from which scientists can identify the chemical composition of the coma gases.


    Rosetta’s imaging and spectroscopy instruments

    In a paper accepted for publication in the journal Astronomy and Astrophysics, scientists report the detections made by Alice from Rosetta’s first four months at the comet, when the spacecraft was between 10 km and 80 km from the centre of the comet nucleus.

    For this study, the team focused on the nature of ‘plumes’ of water and carbon dioxide gas erupting from the comet’s surface, triggered by the warmth of the Sun. To do so, they looked at the emission from hydrogen and oxygen atoms resulting from broken water molecules, and similarly carbon atoms from carbon dioxide molecules, close to the comet nucleus.

    They discovered that the molecules seem to be broken up in a two-step process.

    First, an ultraviolet photon from the Sun hits a water molecule in the comet’s coma and ionises it, knocking out an energetic electron. This electron then hits another water molecule in the coma, breaking it apart into two hydrogen atoms and one oxygen, and energising them in the process. These atoms then emit ultraviolet light that is detected at characteristic wavelengths by Alice.

    Similarly, it is the impact of an electron with a carbon dioxide molecule that results in its break-up into atoms and the observed carbon emissions.

    “Analysis of the relative intensities of observed atomic emissions allows us to determine that we are directly observing the ‘parent’ molecules that are being broken up by electrons in the immediate vicinity, about 1 km, of the comet’s nucleus where they are being produced,” says Paul Feldman, professor of physics and astronomy at the Johns Hopkins University in Baltimore, and lead author of the paper discussing the results.

    By comparison, from Earth or from Earth-orbiting space observatories such as the Hubble Space Telescope, the atomic constituents of comets can only be seen after their parent molecules, such as water and carbon dioxide, have been broken up by sunlight, hundreds to thousands of kilometres away from the nucleus of the comet.

    2
    Comet on 20 May 2015 – NavCam

    “The discovery we’re reporting is quite unexpected,” says Alice Principal Investigator Alan Stern, an associate vice president in the Space Science and Engineering Division of the Southwest Research Institute (SwRI).

    “It shows us the value of going to comets to observe them up close, since this discovery simply could not have been made from Earth or Earth orbit with any existing or planned observatory. And, it is fundamentally transforming our knowledge of comets.”

    “By looking at the emission from hydrogen and oxygen atoms broken from the water molecules, we also can actually trace the location and structure of water plumes from the surface of the comet,” adds co-author Joel Parker, an assistant director in SwRI’s Space Science and Engineering Division in Boulder, Colorado.

    The team likens the break-up of the molecules to the process that has been proposed for the plumes on Jupiter’s icy moon Europa, except that the electrons at the comet are produced by solar photons, while the electrons at Europa come from Jupiter’s magnetosphere.

    The results from Alice are supported by data obtained by other Rosetta instruments, in particular MIRO, ROSINA and VIRTIS, which are able to study the abundance of different coma constituents and their variation over time, and particle detecting instruments like RPC-IES.

    “These early results from Alice demonstrate how important it is to study a comet at different wavelengths and with different techniques, in order to probe various aspects of the comet environment,” says ESA’s Rosetta project scientist Matt Taylor.

    “We’re actively watching how the comet evolves as it moves closer to the Sun along its orbit towards perihelion in August, seeing how the plumes become more active due to solar heating, and studying the effects of the comet’s interaction with the solar wind.”

    More information

    Measurements of the near-nucleus coma of Comet 67P/Churyumov-Gerasimenko with the Alice far-ultraviolet spectrograph on Rosetta, by P Feldman et al is accepted for publication in Astronomy and Astrophysics.

    About Rosetta
    Rosetta is an ESA mission with contributions from its Member States and NASA. Rosetta’s Philae lander was provided by a consortium led by DLR, MPS, CNES and ASI.

    ESA Rosetta Philae Lander
    Rosetta’s Philae lander

    Rosetta is the first mission in history to rendezvous with a comet. It is escorting the comet as they orbit the Sun together. Philae landed on the comet on 12 November 2014. Comets are time capsules containing primitive material left over from the epoch when the Sun and its planets formed. By studying the gas, dust and structure of the nucleus and organic materials associated with the comet, via both remote and in situ observations, the Rosetta mission should become the key to unlocking the history and evolution of our Solar System.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 7:46 am on May 26, 2015 Permalink | Reply
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    From NAOJ: “The Deep Impact Mission Investigates the Origin of Comets” 

    NAOJ

    NAOJ

    Astrophotography・May 26, 2015
    Text by: Seiji Sugita (The University of Tokyo)
    Translation by: Ramsey Lundock (NAOJ)

    1

    Sequential photographs in the mid-infrared show the conditions from one hour to several hours after the impactor released from the Deep Impact flyby spacecraft collided with the Jovian Comet Tempel 1.

    NASA Deep Impact spacecraft
    NASA/Deep Impact spacecreft

    The red color shows carbon-rich material and green shows material rich in silicates (the main component of normal rocks). We can see that for several hours after the collision, the comet’s internal material expanded rapidly out into space, forming a fan shape. The results showed that the internal composition of Jovian (short-period) comets and long-period comets are extremely similar. This is very important data for theories about the origin of comets.

    Long-period Comets and Jovian Comets

    Long-period comets and Jovian comets differ both in terms of their momentum and in terms of the types of dust and gas which they expel. This is thought that they hail primarily from, respectively, the Oort Cloud at a distance of tens of thousands of astronomical units (au) from the Sun and the Kuiper Belt in the vicinity of 30-50 au. Whether the composition of objects is similar or different in these two very different locations is important information for understanding the origin of the Solar System.

    2
    An artist’s rendering of the Oort cloud and the Kuiper belt (inset). Sizes of individual objects have been exaggerated for visibility.

    3
    Known objects in the Kuiper belt beyond the orbit of Neptune (scale in AU; epoch as of January 2015).

    But it was not known whether the difference between these two species of comets is a difference in the depletion levels of gas and dust, or if it is a difference in the internal composition from the time of formation.

    To determine which is correct, it is necessary to peel off the gas-and-dust-depleted surface of a Jovian comet and observe the excavated pristine interior. This experiment was the goal of the Deep Impact Mission.

    On the night of the experiment, we watched the experiment unfold from the summit of Mauna Kea. As the activity started to subside, it came as a big surprise as pristine silicate particles, typical of long-period comets, gushed out from the interior of the Jovian comet. The interiors of both have similar compositions.

    See the full article here.

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    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

    NAOJ Subaru Telescope interior
    Subaru

    ALMA Array
    ALMA

    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
  • richardmitnick 5:21 pm on January 22, 2015 Permalink | Reply
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    From Nature: “Science pours in from Rosetta comet mission” 

    Nature Mag
    Nature

    22 January 2015
    Elizabeth Gibney

    The first major haul of research from the European Space Agency’s Rosetta mission, published in seven papers in Science on 22 January, reveals a rich and diverse landscape on 67P/Churyumov–Gerasimenko, the most studied comet in history. The best images from the haul are pictured below.

    1
    Charting gravity
    Using data from the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) and the Radio Science Investigation instrument, the Rosetta mission team calculated the comet’s gravitational field1. The gravitational potential (pictured) also takes into account a pull caused by the comet’s rotation. The resulting force is greatest on top of the lobes, but it is about six times weaker in the neck region, where dust can lift off more easily. The team also used the data to calculate the comet’s density, finding that the body is relatively fluffy and porous — with a density of around half that of water, giving clues as to its structure and strength.

    2
    Different terrains
    Images taken by the OSIRIS camera reveal vastly different kinds of terrain, including dunes, ripples and fractures2. Rosetta scientists have split the comet into regions defined by surface structure (see false-colour image), with each named after an Egyptian god. Hatmehit, for example, is a smooth depression on the ‘head’ of the duck-shaped comet that could be a dust-filled impact crater. Other areas, such as Seth and Hathor, are rough with steep cliff-like structures. However, the porosity of the comet means that rock-like structures are in fact compacted dust. Many structures look as though they are formed by gas moving dust around the surface, say the authors, in the same way that wind shapes sand in a desert

    3
    Clues to the origins
    Detailed pictures, at their best with a resolution of 15 centimetres per pixel, show structures that could hint at the comet’s history1. Three-metre-wide features nicknamed “goosebumps”, pictured here running down the inside of a pit in the Seth region, are found all over the comet. Holger Sierks of the Max Planck Institute for Solar System Research in Göttingen, Germany, who is principal investigator on the OSIRIS camera instrument, says that the pebble-like shapes could hint at the scale on which grains of dust and ice first clumped together in the early Solar System. “The hypothesis is these might be the building blocks of comets,” he says.

    4
    The neck riddle
    Data from several instruments show that the comet’s neck is the source of most of its streaming gas and dust. To understand why the region is so active, the Rosetta team looked at how much thermal energy hits the surface per 12.4-hour rotation (left) and per 6.5-year solar orbit (right). The neck receives less energy from the Sun than the rest of the comet because it is shaded, but they found that a suntrap effect from radiation bouncing between opposite cliff walls goes some way towards compensating for that. Other possible reasons for the region’s high activity include its low gravitational pull, which means that little force is needed to blow dust away, and that the region might have a different composition than other regions, or have more ready access to water beneath the surface1. The team has still to answer whether the neck denotes a join between two comets or has been carved out of a single comet by erosion. Evidence of differences between the two lobes would indicate the former, but so far the two lobes seem to have very similar structures, says Sierks.

    6
    Coming from afar
    This visible and infrared portrait of 67P’s surface, obtained by the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS), shows an abundance of opaque, organic compounds, but very little water ice. This would be consistent with an origin for the comet in the distant Kuiper belt — beyond the orbit of Neptune — rather than closer to Jupiter, as its current orbit would suggest.

    References
    1.Sierks, H. et al. Science http://dx.doi.org/10.1126/science.aaa1044 (2015)
    2.Thomas, N. et al. Science http://dx.doi.org/10.1126/science.aaa0440 (2015)
    3.Hässig, M. et al. Science http://dx.doi.org/10.1126/science.aaa0276 (2015)
    4.Capaccioni, F. et al. Science http://dx.doi.org/10.1126/science.aaa0628 (2015)
    6.Gulkis, S. et al. Science http://dx.doi.org/10.1126/science.aaa0709 (2015)

    Additional reporting by Davide Castelvecchi

    See the full article here.

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  • richardmitnick 7:14 am on January 17, 2015 Permalink | Reply
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    From JPL: “NASA’s NEOWISE Images Comet C/2014 Q2 (Lovejoy) “ 

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    1
    Image credit: NASA/JPL-Caltech

    Comet C/2014 Q2 (Lovejoy) is one of more than 32 comets imaged by NASA’s NEOWISE mission from December 2013 to December 2014. This image of comet Lovejoy combines a series of observations made in November 2013, when comet Lovejoy was 1.7 astronomical units from the sun. (An astronomical unit is the distance between Earth and the sun.)

    The image spans half of one degree. It shows the comet moving in a mostly west and slightly south direction. (North is 26 degrees to the right of up in the image, and west is 26 degrees downward from directly right.) The red color is caused by the strong signal in the NEOWISE 4.6-micron wavelength detector, owing to a combination of gas and dust in the comet’s coma.

    Comet Lovejoy is the brightest comet in Earth’s sky in early 2015. A chart of its location in the sky during dates in January 2015 is at http://photojournal.jpl.nasa.gov/catalog/PIA19103 .

    For more information about NEOWISE (the Near-Earth Object Wide-field Survey Explorer), see http://neowise.ipac.caltech.edu/.

    NASA Wise Telescope
    NASA/Wise

    See the full article here.

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    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 9:08 am on December 8, 2014 Permalink | Reply
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    From AAAS: “Comet dust found in Antarctica” 

    AAAS

    AAAS

    5 December 2014
    Ilima Loomis

    Researchers have discovered comet dust preserved in the ice and snow of Antarctica, the first time such particles have been found on Earth’s surface. The discovery unlocks a promising new source of this material. The oldest astronomical particles available for study, comet dust can offer clues about how our solar system formed.

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    A single particle of comet dust collected from Antarctic ice, as seen through an electron microscope. Takaaki Noguchi

    “It’s very exciting for those of us who study these kinds of extraterrestrial materials, because it opens up a whole new way to get access to them,” says Larry Nittler, a planetary scientist in the Department of Terrestrial Magnetism at the Carnegie Institution for Science in Washington, D.C., who was not involved with the research. “They’ve found a new source for something that’s very interesting and very rare.”

    Until recently, the only way scientists could collect “chondritic porous interplanetary dust particles,” or comet dust, without going to space has been by flying research planes high in the stratosphere. It’s painstaking work: Several hours of flying time typically yield one particle of dust. Working with such small samples significantly limits the kinds of tests and analysis scientists can perform on the material, says study co-author John Bradley, an astromaterials scientist at the Hawaii Institute of Geophysics and Planetology of the University of Hawaii, Manoa.

    The researchers found a bigger haul of the particles in Antarctica, he notes. “Two to four more orders of magnitude mass of material is potentially collectible this way,” he says. “I think it could precipitate a paradigm shift in the way these kinds of materials are collected.”

    The dust gathered in Antarctica is also cleaner. Right now, scientists gathering comet dust by plane use plates coated with silicon oil to trap the particles like flies in flypaper. That leaves them contaminated with both the oil and the organic compounds later used to clean them, making it especially difficult for scientists who want to study what organic material they might contain.

    Comparing the particles found in Antarctica with the ones collected in the stratosphere will help scientists figure out which components of the dust are part of their natural chemical makeup and which come from contaminants, Nittler says.

    In 2010, a team of French scientists reported that they had found dense, unusually carbon-rich comet particles in the Antarctic snow, but this is the first time more typical comet dust has been found and its identity confirmed. Scientists had thought the highly porous, extremely fragile particles couldn’t survive on Earth.

    To find them, the researchers collected snow and ice from two different sites in Antarctica over several years, starting in 2000. By melting the ice and filtering the water, they collected more than 3000 micrometeorites, tiny particles from space that were 10 microns in diameter or larger. Analyzing the micrometeorites one by one under a stereomicroscope over a period of 5 years yielded more than 40 particles with the characteristics of comet dust. A closer analysis found they were indistinguishable from comet dust collected in the stratosphere, and they also matched samples collected from the coma of a comet by NASA’s Stardust mission in 2006, the researchers report online ahead of print in Earth and Planetary Science Letters.

    NASA Stardust spacecraft
    NASA Stardust spacecraft schematic
    NASA/Stardust

    “Our result shows that such fragile particles can be preserved not only in … snow, but also in ice,” says the study’s lead author, Takaaki Noguchi, a meteorite researcher at Kyushu University in Fukuoka, Japan.

    A good next step would be to make a more detailed analysis of the organic material in the particles, says meteorite researcher Cécile Engrand of the Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse of Paris-Sud University in Orsay, a co-author of the earlier French research. “The study of these cometary particles will help shed more light on the material that served for planetary formation,” she says. “They are the best witnesses that we have of that period of time.”

    See the full article here.

    The American Association for the Advancement of Science is an international non-profit organization dedicated to advancing science for the benefit of all people.

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  • richardmitnick 5:48 pm on December 3, 2014 Permalink | Reply
    Tags: , , , , , Comets, ,   

    From ESA: “The quest for organic molecules on the surface of 67P/C-G” 

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    European Space Agency

    From The Rosetta Blog

    ESA Rosetta spacecraft
    Rosetta

    02/12/2014
    This blog post is contributed by Ian Wright and his colleagues from the Ptolemy team.

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    Ptolemy on Philae Lander

    For scientists engaged with large complex projects like Rosetta, there is always a delightful period early on when, unbound by practical realities, it is possible to dream. And so it was that at one time the scientists were thinking about having a lander with the capability to hop around a comet’s surface. In this way it would be possible to make measurements from different parts of the comet.

    Interestingly, this unplanned opportunity presented itself on 12 November 2014, when Philae landed not once but three times on Comet 67P/Churyumov-Gerasimenko.

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    Comet 67P/Churyumov-Gerasimenko

    The Ptolemy instrument on Philae is a compact mass spectrometer designed to measure the composition of the materials making up 67P/C-G, with a particular focus on organic molecules and mineral components. Earlier in 2014, Ptolemy had collected data at distances of 15,000, 13,000, 30, 20, and 10 km from the comet, while Philae was still attached to Rosetta.

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    But from 12 to 14 November, along with some other instruments on the lander, Ptolemy had the chance to operate at more than one location on the comet’s surface.
    Rosetta’s OSIRIS narrow-angle camera images of Philae’s first touchdown on the comet. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

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    OSIRIS

    Ptolemy performed its first ‘sniffing’ measurements on the comet just after the initial touchdown of Philae. At almost exactly the same moment, the OSIRIS camera on Rosetta was imaging Philae flying back above the surface after the first bounce.

    Later, once Philae had stopped at its final landing site, Ptolemy then made six subsequent sets of measurements, sniffing the comet’s atmosphere at the surface between 13 and 14 November. Finally, a slightly different experiment was also conducted on 14 November, which was completed only 45 minutes before Philae went into hibernation as its primary battery was exhausted.

    For this “last gasp” experiment, the team used a specialised oven, the so-called “CASE” oven, to determine the composition of volatiles (and perhaps any particulates) that had accumulated in it. The Ptolemy team also used the same opportunity to reconfigure their analytical procedures, to see if they could make some isotopic measurements. Unfortunately, there was no chance to use Ptolemy in conjunction with SD2, as this was confined to the sister instrument, COSAC, given the limited power and time available.

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    The experiments conducted by Ptolemy on the surface of Comet 67P/C-G. Table courtesy of the Ptolemy team.

    Because of the relatively high power consumption of Ptolemy, it was a race against the clock. The battery had to hold out, both to perform the measurements and to relay the data back to Rosetta and then home. For those involved, it’s hard to describe the shared emotions on that day, helplessly watching a voltage heading towards the end-stop.

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    Scientists from the Ptolemy team at the Lander Control Centre at DLR in Cologne, Germany, during the night between 14 and 15 November 2014, just before Philae went into hibernation. Photo courtesy of Ian Wright.

    Nevertheless, the very good news is that Ptolemy definitely returned data from its various stops on the comet. However, the data are complex and will require careful analysis: this will take time. Also, because the instrument was operated in ways that hadn’t initially been planned for, it will be necessary to go back into the laboratory to run some simulated tests, to ensure that the on-comet data obtained in similar configurations can be understood.

    In the first instance, however, the team will be concentrating on the data acquired immediately after the first touchdown. It will be fascinating to compare the rich spectrum of organic compounds detected by Ptolemy with the measurements made by COSAC about 14 minutes later.

    The Ptolemy team has lots of questions. Exactly what organic compounds are present and in what ratios? How did things change between the various sets of measurements? What does these data tell us about the composition of the 10–20 cm depth of surface dust that got kicked up during the first bounce? And what can these materials tell us about the fundamental make-up of comets?

    The team is looking forward to making these analyses over the coming months and sharing the results with you.

    See the full article here.

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    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 5:36 pm on December 1, 2014 Permalink | Reply
    Tags: , , Comets, , , NASA SOHO   

    From ESA: “Comet ISON disintegrates” 

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    European Space Agency

    01/12/2014
    No Writer Credit
    ESA/NASA

    Some had hoped comet ISON would be the comet of the century, lighting Earth’s skies during the latter months of 2013. Instead, it was barely visible for ground-based observers, but the Solar and Heliospheric Observatory (SOHO) had a ring-side seat to watch its disintegration.

    is
    This new view of Comet C/2012 S1 (ISON) was taken with the TRAPPIST national telescope at ESO’s La Silla Observatory on the morning of Friday 15 November 2013. Comet ISON was first spotted in our skies in September 2012, and will make its closest approach to the Sun in late November 2013.

    ESO TRAPPIST telescope
    ESO Trappist Interior
    ESO/Trappist national telescope

    ESO LaSilla Long View
    ESO/LaSilla

    TRAPPIST has been monitoring comet ISON since mid-October, using broad-band filters like those used in this image. It has also been using special narrow-band filters which isolate the emission of various gases, allowing astronomers to count how many molecules of each type are released by the comet.

    Comet ISON was fairly quiet until 1 November 2013, when a first outburst doubled the amount of gas emitted by the comet. On 13 November, just before this image was taken, a second giant outburst shook the comet, increasing its activity by a factor of ten. It is now bright enough to be seen with a good pair of binoculars from a dark site, in the morning skies towards the East. Over the past couple of nights, the comet has stabilised at its new level of activity.

    These outbursts were caused by the intense heat of the Sun reaching ice in the tiny nucleus of the comet as it zooms toward the Sun, causing the ice to sublimate and throwing large amounts of dust and gas into space. By the time ISON makes its closest approach to the Sun on 28 November (at only 1.2 million kilometres from its surface — just a little less than the diameter of the Sun!), the heat will cause even more ice to sublimate. However, it could also break the whole nucleus down into small fragments, which would completely evaporate by the time the comet moves away from the Sun’s intense heat. If ISON survives its passage near the Sun, it could then become spectacularly bright in the morning sky.

    The image is a composite of four different 30-second exposures through blue, green, red, and near-infrared filters. As the comet moved in front of the background stars, these appear as multiple coloured dots.
    TRAPPIST (TRAnsiting Planets and PlanetesImals Small Telescope) is devoted to the study of planetary systems through two approaches: the detection and characterisation of planets located outside the Solar System (exoplanets), and the study of comets orbiting around the Sun. The 60-cm national telescope is operated from a control room in Liège, Belgium, 12 000 km away.

    so

    This image is a montage spanning three days from 28–30 November 2013. The comet enters the image at the lower right, passes round the Sun and exits the frame towards the upper right. The bright star to the lower left is the red supergiant star Antares.

    Astronomers had been tracking the comet for more than a year as it edged closer to the Sun, and by late November it had passed into the field of view of SOHO’s LASCO C3 camera. It was to skim the Sun, just 1 165 000 km above the fiery surface.

    NASA SOHO
    NASA/SOHO

    This is approximately 50 times closer to the Sun than innermost planet Mercury, and the comet was officially termed a ‘sungrazer’. If it survived the encounter it was expected to become extremely bright and be a well-placed object, visible to the naked eye in Earth’s night sky.

    Calculations based on its orbit show that ISON began its journey towards the Sun about 3 million years ago, dislodged from its distant orbit by a passing star. Now, its fate would be sealed within days.

    On 27 November, the comet brightened dramatically by a factor of about ten. Yet just before it reached closest approach to the Sun, it began to fade. This was a strong indicator that the heart of the comet, the icy nucleus, had broken up. Many expected it would disperse completely but, at first, it looked as if they were wrong.

    Comet ISON appeared to survive the close approach, emerging on the other side of the Sun. Some still hoped for a bright display in the night skies. But they were to be disappointed. Quickly, the comet began to disappear. A recent analysis of SOHO data showed that the nucleus had indeed disintegrated just before closest approach to the Sun. Nothing appreciable was left of it, just a lot of dust and vapour.

    The disintegration of comet ISON provided scientists with an exceptional chance to see a comet inside and out. Another rare opportunity is being provided by comet 67P/Churyumov-Gerasimenko. ESA’s Rosetta spacecraft caught up with this comet early in August 2014 and deployed the lander Philae to the surface in November. The orbiter will accompany comet 67P/C-G along its orbit and through its closest approach to the Sun, which takes it between the orbits of Mars and Earth. While this comet is unlikely to suffer the same fate as comet ISON, it will provide an unsurpassed insight into the nature of comets.

    p67

    ESA Rosetta spacecraft
    ESA/Rosetta

    ESA Rosetta Philae Lander

    See the full article here.

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    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 2:51 pm on November 19, 2014 Permalink | Reply
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    From ESA: “Rosetta Continues into its Full Science Phase” 

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    European Space Agency

    19 November 2014
    No Writer Credit

    With the Philae lander’s mission complete, Rosetta will now continue its own extraordinary exploration, orbiting Comet 67P/Churymov–Gerasimenko during the coming year as the enigmatic body arcs ever closer to our Sun.

    ESA Rosetta spacecraft
    ESA/Rosetta

    p67
    Comet Churyumov–Gerasimenko as seen by Rosetta

    Last week, ESA’s Rosetta spacecraft delivered its Philae lander to the surface of the comet for a dramatic touchdown.

    ESA Rosetta Philae Lander
    Rosetta’s Philae Lander

    The lander’s planned mission ended after about 64 hours when its batteries ran out, but not before it delivered a full set of results that are now being analysed by scientists across Europe.

    Rosetta’s own mission is far from over and the spacecraft remains in excellent condition, with all of its systems and instruments performing as expected.

    “With lander delivery complete, Rosetta will resume routine science observations and we will transition to the ‘comet escort phase’,” says Flight Director Andrea Accomazzo.

    “This science-gathering phase will take us into next year as we go with the comet towards the Sun, passing perihelion, or closest approach, on 13 August, at 186 million kilometres from our star.”

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    Rosetta control room

    On 16 November, the flight control team moved from the large Main Control Room at ESA’s Space Operations Centre in Darmstadt, Germany, where critical operations during landing were performed, to a smaller Dedicated Control Room, from where the team normally flies the craft.

    Since then, Rosetta has performed a series of manoeuvres, using its thrusters to begin optimising its orbit around the comet for the 11 scientific instruments.

    “Additional burns planned for today, 22 and 26 November will further adjust the orbit to bring it up to about 30 km above the comet,” says Sylvain Lodiot, Spacecraft Operations Manager.

    From next week, Rosetta’s orbit will be selected and planned based on the needs of the scientific sensors. After arrival on 6 August, the orbit was designed to meet the lander’s needs.

    On 3 December, the craft will move down to height of 20 km for about 10 days, after which it will return to 30 km.

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    Rosetta path after 12 November

    With the landing performed, all future trajectories are designed purely with science as the driver, explained Laurence O’Rourke and Michael Küppers at the Rosetta Science Operations Centre near Madrid, Spain.

    “The desire is to place the spacecraft as close as feasible to the comet before the activity becomes too high to maintain closed orbits,” says Laurence.

    “This 20 km orbit will be used by the science teams to map large parts of the nucleus at high resolution and to collect gas, dust and plasma at increasing activity.”

    Planning the science orbits involves two different trajectories: ‘preferred’ and ‘high-activity’. While the intention is always to fly the preferred path, Rosetta will move to the high-activity trajectory in the event the comet becomes too active as it heats up.

    “This will allow science operations to continue besides the initial impact on science planning that such a move would entail,” adds Michael.

    “Science will now take front seat in this great mission. It’s why we are there in the first place!” says Matt Taylor, Rosetta Project Scientist.

    “The science teams have been working intensively over the last number of years with the science operations centre to prepare the dual planning for this phase.”

    When solar heat activates the frozen gases on and below the surface, outflowing gas and dust particles will create an atmosphere around the nucleus, known as the coma.

    Rosetta will become the first spacecraft to witness at close quarters the development of a comet’s coma and the subsequent tail streaming for millions of kilometres into space. Rosetta will then have to stay further from the comet to avoid the coma affecting its orbit.

    In addition, as the comet nears the Sun, illumination on its surface is expected to increase. This may provide sufficient sunlight for the DLR-operated Philae lander, now in hibernation, to reactivate, although this is far from certain.

    Early next year, Rosetta will be switched into a mode that allows it to listen periodically for beacon signals from the surface.


    Rosetta orbiting the comet

    Regular updates on Rosetta’s continuing mission and its scientific explorations will be posted in the mission blog, via http://blogs.esa.int/rosetta.

    See the full article, with video, here.

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    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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