quote:Herschel scans hidden Milky Way
A remarkable view of our galaxy has been obtained by Europe's billion-euro Herschel Space Observatory.
The telescope was put in a special scanning mode to map a patch of sky.
The images reveal in exquisite detail the dense, contorted clouds of cold gas that are collapsing in on themselves to form new stars.
Herschel, which has the largest mirror ever put on an orbiting telescope, was launched in May as a flagship mission of the European Space Agency.
It is tuned to see far-infrared wavelengths of light and is expected to give astronomers significant insights into some of the fundamental processes that shape the cosmos.
Herschel's great advantage is that its sensitivity allows it to see things that are beyond the vision of other space telescopes, such as Hubble.
A prime goal is to understand the mechanisms that control the earliest phases of stellar evolution.
Rich data return
Herschel's special scanning mode means it has to shift its gaze back and forth across an area of sky, which in this case was about 16 times as big as the size of the Moon as viewed from Earth.
The observatory is tuned to see the Universe in the far-infrared
Its 3.5m diameter mirror is the largest ever flown in space
Herschel can probe clouds of gas and dust to see stars being born
It will investigate how galaxies have evolved through time
The mission will end when its helium refrigerant boils off
The telescope was looking towards the plane of our Milky Way Galaxy, in the direction of the Southern Cross constellation.
The scanning mode works with two of Herschel's three instruments operating in tandem.
The UK-led Spire camera responds to longer wavelengths of light (250-500 microns - that is about 500-1,000 times longer than the wavelengths of light we detect with our eyes).
The German-led Pacs camera covers shorter wavelengths (70-170 microns).
Their pictures reveal a chaotic scene of gas and dust, and stars in all stages of development.
The material being observed is very cold - typically less than minus 170C (100 kelvin).
Anomaly investigation
Scientists say the images are information-rich.
"Our wavelength coverage is telling us details about the physics," explained Professor Matt Griffin, of Cardiff University, who is the Spire principal investigator.
"Spire is particularly good at seeing the cold and extended material which might correspond, for instance, to the earliest stages of star formation.
"Pacs is slightly more sensitive to what we would call warmer material, although by any normal standards it is still extremely cold; and that material might be closer to regions where stars have already formed and have been heated up by the young stellar objects."
Herschel intends to study large regions of the Milky Way in its combined Spire-Pacs scanning mode. The instruments will, of course, also work independently.
The mission is due to go into routine operations in the next few weeks. However, its third instrument is currently down after experiencing a fault.
Engineers can switch to a back-up system to reactivate the Heterodyne Instrument for the Far Infrared (HiFi), but they do not intend to do that until they have satisfied themselves the cause the anomaly is properly understood.
The Dutch-led HiFi is a spectrometer that will identify elements and molecules in the clouds of gas and dust which give rise to stars.
Bron: BBC.
quote:New ring detected around Saturn
By Jonathan Amos
Science reporter, BBC News
Saturn (Nasa)
The outer E-ring on Saturn extends about 240,000km into space
A colossal new ring has been identified around Saturn.
The dusty hoop extends some 13 million km (eight million miles) from the planet, about 50 times further out into space than its more familiar rings.
Scientists tell the journal Nature that the tenuous ring is probably made up of debris kicked off Saturn's moon Phoebe by small impacts.
They think this dust then migrates towards the planet where it is picked up by another Saturnian moon, Iapetus.
The discovery would appear to resolve a longstanding mystery in planetary science: why the walnut-shaped Iapetus has a two-tone complexion, with one side of the moon significantly darker than the other.
"It has essentially a head-on collision. The particles smack Iapetus like bugs on a windshield," said Anne Verbiscer from the University of Virginia, US.
Observations of the material coating the dark face of Iapetus indicate it has a similar composition to the surface material on Phoebe.
The scale of the new ring feature is astonishing. Nothing like it has been seen elsewhere in the Solar System.
The more easily visible outlier in Saturn's famous bands of ice and dust is its E-ring, which encompasses the orbit of the moon Enceladus. This circles the planet at a distance of just 240,000km.
The newly identified torus is not only much broader and further out, it is also tilted at an angle of 27 degrees to the plane on which the more traditional rings sit.
This in itself strongly links the ring's origin to Phoebe, which also takes a highly inclined path around Saturn.
Scientists suspected the ring might be present and had the perfect tool in the Spitzer space telescope to confirm it.
The US space agency observatory is well suited to picking up the infrared signal expected from cold grains of dust about 10 microns (millionths of a metre) in size.
The ring would probably have a range of particle sizes - some bigger than this, and some smaller - and modelling indicates the pressure of sunlight would push the smallest of these grains towards the orbit of Iapetus, which is circling Saturn at a distance of 3.5 million km.
"The particles are very, very tiny, so the ring is very, very tenuous; and actually if you were standing in the ring itself, you wouldn't even know it," Dr Verbiscer told BBC News.
"In a cubic km of space, there are all of 10-20 particles."
Indeed, so feeble is the ring that scientists have calculated that if all the material were gathered up it would fill a crater on Phoebe no more than a kilometre across.
The moon is heavily pockmarked. It is clear that throughout its history, Phoebe has been hit many, many times by objects.
Some will also have been orbiting Saturn; others will have come from deep space.
Bron: BBC.
quote:Updated SMART-1 Image Of New Target For LCROSS Impact
by Staff Writers
Paris, France (ESA) Oct 08, 2009
New LCROSS impact target Cabeus: Mosaic of 4 images taken by the Advanced Moon Imaging Experiment (AMIE) on board ESA's SMART-1 mission. The SMART-1 images forming the mosaic have been taken at different epochs with different illumination conditions: in January 2005 from a distance of 1037 km and on February 2006 from a distance of 622 km. The SMART-1 AMIE mosaic size is 100 km. The dots at the center of the image indicate the impact points for the LCROSS Centaur stage and shepherd spacecraft well placed within the shadowed area. Image credit: B.Grieger, B.H. Foing and ESA/SMART-1/ AMIE team
The European Space Agency's SMART-1 team has released an updated image of the future impact site of NASA's Lunar Crater Observation and Sensing Satellite (LCROSS), after the LCROSS team announced a new target last week. LCROSS will search for water ice on the Moon by making two impacts into a crater named Cabeus at the lunar South Pole. The impacts are scheduled for 11:31:19 UTC and 11:35:45 UTC on 9 October 2009.
Bjoern Grieger, the liaison scientist for SMART-1's AMIE camera, and Bernard Foing, ESA SMART-1 Project Scientist, have searched through SMART-1's database for images of Cabeus, taken four years ago. The SMART-1 images are at high resolution as the spacecraft was near its closest distance of 500 km from the South Pole.
The SMART-1 images of LCROSS potential targets were discussed on 18 September at lunar sessions of European Planetary Science Congress (EPSC) in Potsdam, Germany.
The Cabeus crater interior is permanently shadowed, so ice lying inside the crater could be protected from the Sun's harsh rays. LCROSS will send the upper stage Centaur rocket crashing into Cabeus and a shepherd spacecraft will fly into the plume of dust generated and measure its properties before making a second impact with the lunar surface. Astronomers will observe both impacts using ground and space-based telescopes.
The SMART-1 spacecraft also concluded its mission with a controlled bouncing impact on 3 September 2006. The event was observed with ground-based telescopes (a "dry run" for LCROSS), and the flash from the impact was detected at infrared wavelengths.
"The Cabeus topographic features as observed by SMART-1 vary greatly during the lunar rotation and the yearly seasons due to the polar grazing illumination conditions", said Foing.
"The floor of Cabeus near LCROSS targets shows a number of small craters and seems old enough to have accumulated water ice delivered from comets and water-rich asteroids, and might have kept it frozen in its shadowed area."
"These ESA SMART-1 observations of the Cabeus crater can help in the final planning and interpretation of LCROSS impact observations", he added.
quote:ESA schort Mars-missie op
Van onze verslaggever Peter van Ammelrooy
Gepubliceerd op 13 oktober 2009 12:37, bijgewerkt op 13 oktober 2009 14:41
AMSTERDAM - De Europese ruimtevaartorganisatie ESA past zijn ambities aan het budget aan en gaat later naar Mars – met hulp van de Amerikanen.
Tijdens een vergadering in Parijs is besloten om ExoMars, een expeditie naar de rode planeet, met twee jaar uit te stellen, tot 2018, meldt de BBC. De missie zal worden uitgevoerd in samenwerking met de Verenigde Staten. De wijzigingen waren eerder dit jaar al voorgesteld door de ESA omdat de ministers van de lidstaten in november onvoldoende geld beschikbaar stelden voor het project.
Met ExoMars wil de ESA een kunstmaan in een baan om Mars brengen en een robotkarretje op het oppervlak van de planeet laten landen. Deze rover is voorzien van een boor die tot twee meter diep in de bodem kan boren. Net als de NASA-robotjes Spirit en Opportunity moet de missie uitwijzen of er leven op Mars is of is geweest.
In november vorig jaar besloten de ministers van de lidstaten van de ESA 850 miljoen euro opzij te zetten voor ExoMars. Dat is te weinig om de missie te bekostigen.
Geldgebrek
Ook de aangepaste plannen moeten nog door de politieke molen. ExoMars zit al een jaar of vijf in de pijplijn. Oorspronkelijk zouden sonde, landingsvaartuig en robot in 2011 worden gelanceerd. Maar omdat de grootste financier van het project, Italië, zijn toezeggingen niet nakwam is de missie al drie keer uitgesteld.
De nieuwe plannen voorzien wel in een kleinschalige, voorbereidende missie met een kunstmaan die om Mars draait en een kleine, vaste sonde die op de planeet landt. Die verkenner zou in 2016 worden gelanceerd.
De Verenigde Staten willen in 2013 een nieuwe robot, Curiosity (die tot mei dit jaar als de Mars Science Laboratory MSL bekend stond), naar Mars sturen. Ook dat is al weer twee jaar later dan gepland. Die missie wordt daarmee waarschijnlijk 400 miljoen dollar duurder – een stijging die bovenop de geraamde kosten van 2 miljard dollar komt.
Bron: De Volkskrant.
quote:European commands space station
Belgian astronaut Frank De Winne has spoken of his pride at taking command of the International Space Station.
The European Space Agency astronaut is the first national outside of the US and Russia to lead a crew on the orbiting platform.
De Winne took the role at the weekend when the previous commander, Gennady Padalka, left to return to Earth.
The Belgian told reporters on Tuesday that his appointment was a great moment for the European Astronaut Corps.
"I have always been proud to be European and the Europeans of course have a big heritage as explorers; and so, therefore, for me, it is a big honour to be the first European to be a commander of the space station," he said.
De Winne made his remarks during a live link-up with the ISS. He took questions while floating inside the Columbus module, Europe's science lab attached to the platform.
The Esa astronaut launched to the station in May. He will stay aboard the platform until December when he is due to fly back to Earth in a Soyuz capsule.
Bron: BBC, lees meer…
quote:[UPD] Meteoor boven Nederland ontploft
Volgens Twitter is ons land zojuist aan een ramp ontsnapt. Vele Twitteraars werden rond zeven uur vanavond opgeschrikt door een meteoor. Deze is onder andere gesignaleerd boven Zwolle, Ede, Breda, Huizen en Arnhem.
Volgens sommige gebruikers zijn we nog niet van de problemen af. De vuurbal zou zijn neergestort in de Noordzee. [Knip]
UPDATE
Veel Nederlanders hebben vanavond rond zeven uur een vuurbol in de lucht gezien. De Groningse sterrenkundige Theo Jurriens bevestigde dat het om een zeer heldere meteoor ging die op een gegeven moment in drie stukken uiteenspatte.
Jurriens zei uit heel Nederland ongeveer honderd meldingen te hebben ontvangen van mensen die de vuurbol hebben gezien. Het KNMI meldde ook een behoorlijk aantal telefoontjes te hebben ontvangen.
Foto Credit Jan de Vries
quote:Een heuse tsunami zou ons land nu bedreigen. We houden ons hart vast, het is dan ook al bijna 2012.
Echt onzin talk... Zal het ff weghalenquote:
quote:Op dinsdag 13 oktober 2009 23:01 schreef -CRASH- het volgende:
[..]
Echt onzin talk... Zal het ff weghalen
Meteoor gezien boven Nederland en Belgiëquote:Op dinsdag 13 oktober 2009 23:24 schreef ExperimentalFrentalMental het volgende:
Cool!
Heeft iemand de meteoor gezien?
quote:Op dinsdag 13 oktober 2009 23:39 schreef Iblis het volgende:
[..]
Meteoor gezien boven Nederland en België
Er is een heel topic over met FOK!ers die het gezien hebben.
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