Rosetta i fin form

Fora ASTRO-FORUM GENEREL ASTRONOMI Rosetta i fin form

  • Dette emne har 218 svar og 27 stemmer, og blev senest opdateret for 8 år, 3 måneder siden af mikael_joe. This post has been viewed 7546 times
Viser 15 indlæg - 196 til 210 (af 219 i alt)
  • Forfatter
    Indlæg
  • #124718

    Julius
    Deltager
      • Nova

      “Although the ovens worked correctly, the scientists do not yet know how
      much – if any – material was actually delivered to the ovens by SD2, or
      whether the instruments sampled dust or gas that entered the chamber
      during the touchdown.”
      http://blogs.esa.int/rosetta/2014/11/19/did-philae-drill-the-comet/

      MrJulius2014-11-19 18:55:43

      #125209

      Torben Taustrup
      Admin
        • Neutron star

        67P – P for potato

        67P er kartoffelformet Wink
        Jeg fik lige reddet den inden den blev skrællet. Efterfølgende er den indgået som en af
        1ngredienserne i en gryde skipperlabskovs.

        TOC Observatory - "http://tocobs.org -14.5″ – f:4,2 Newt - Atik383 - ZWO2600-mono – SXV H9 - QHY8L-color - SkyWatcher 80 mm ED refraktor - 60 mm F:6 apocromat - TAL Apolar 125 f : 7,5.

        #125218

        edbbob
        Deltager
          • Super Nova

          Har du spist den?!? Hva så med Phil?

          #125220

          Torben Taustrup
          Admin
            • Neutron star

            Ups! Den havde jeg sgu ikke tænkt på Wink
            Jeg melder lige tilbage, hvis den på et senere tidspunkt skulle have sat sig fast mellem et par
            tænder. Det er nok det sted, hvor Solen skinner mindst.

            TOC Observatory - "http://tocobs.org -14.5″ – f:4,2 Newt - Atik383 - ZWO2600-mono – SXV H9 - QHY8L-color - SkyWatcher 80 mm ED refraktor - 60 mm F:6 apocromat - TAL Apolar 125 f : 7,5.

            #125608

            nightsky
            Deltager
              • Neutron star

              Det kan man da bestemt kalde et spændende resultat. Vand på jorden kommer i hvert fald
              ikke fra kometer som 67P/Churyumov–Gerasimenko, og måske slet ikke fra kometer overhovedet.

              http://www.esa.int/Our_Activities/Space_Science/Rosetta/Rosetta_fuels_debate_on_origin_of_Earth_s_oceans

              http://blogs.esa.int/rosetta/2014/12/10/rosetta-fuels-debate-on-origin-of-earths-oceans/

              #125757

              nightsky
              Deltager
                • Neutron star

                Første farvebillede (RGB) af 67P/Churyumov-Gerasimenk.

                Den er grå, næsten lige så sort som kul. Rødt lys reflekteres en lille smule mere end andre
                farver, da størrelsen af overfladepartiklerne er lille. Iflg. pressemeddelelsen er det noget man
                også ser andre steder i solsystemet.

                RGB billedet afslører også at der ikke er is på overfladen, fordi man ikke ser øget reflektion i
                det blå filter.

                Til info:
                OSIRIS to kameraer
                Narrow – 250 til 1000nm
                Wide – 240 til 720nm

                Super spændende PDF om kameraet, filter .m.m
                http://pdssbn.astro.umd.edu/holdings/ro-a-osiwac-3-ast1-steinsflyby-v1.4/document/osiris_ssr/osiris_ssr.pdf

                Narrow filter opsætning:
                8x Neutral 640 520 Passes only 5% of light (neutral density filter)
                3x NFP-Vis 600 >600 Refocusing lens for near-field imaging
                2x FFP-Vis 600 600 Refocusing lens for near-field imaging
                1x FFP-UV 600 >600 Clear filter for far-field imaging with wheel 2 filters
                x1 FFP-IR 600 >600 Clear filter for far-field imaging with wheel 1 filters
                x5 Far-UV 269.3 53.6 Surface spectral reflectance
                x6 Near-UV 360.0 51.1 Surface spectral reflectance
                x4 Blue 480.7 74.9 Surface spectral reflectance
                x3 Green 535.7 62.4 Surface spectral reflectance
                x2 Orange 649.2 84.5 Surface spectral reflectance
                x7 Hydra 701.2 22.2 Water of hydration band
                x8 Red 743.7 64.1 Surface spectral reflectance
                5x Ortho 805.3 40.5 Orthopyroxene
                4x Near-IR 882.1 65.9 Surface spectral reflectance
                6x Fe2O3 931.9 34.9 Iron-bearing minerals
                7x IR 989.3 38.2 IR surface reflectance

                Wide filter opsætning:
                1x Empty — — Empty position for use with wheel 2
                x1 Empty — — Empty position for use with wheel 1
                3x UV245 246.2 14.1 Continuum surface spectral reflectance
                4x CS 259.0 5.6 CS gas emission
                5x UV295 295.9 10.9 Continuum for OH
                6x OH-WAC 309.7 4.1 OH emission near nucleus
                7x UV325 325.8 10.7 Continuum for OH, surface spectral reflectance
                8x NH 335.9 4.1 NH gas emission
                x3 UV375 375.6 9.8 Continuum for CN, surface spectral reflectance
                x4 CN 388.4 5.2 CN gas emission
                2x Green 537.2 63.7 Dust continuum
                x5 NH2 572.1 11.5 NH2 gas emission
                x6 Na 590.7 4.7 Sodium gas emission
                x8 VIS610 612.6 9.8 Continuum for OI, surface spectral reflectance
                x7 OI 631.6 4.0 O gas emission for dissociation of H2O
                x2 Red 629.8 156.8 Broadband filter for nucleus and asteroid detection
                and redundancy with NAC

                Der er et par filtre jeg kunne ønske mig til teleskopet:
                F.eks. x7 Hydra 701,2 – Ortho 5x 805,3 – x4 CN 388,4 m.fl. man kan sikkert få en del sjov af disse.

                Nightsky2014-12-14 15:30:59

                #126140

                Torben Taustrup
                Admin
                  • Neutron star

                  Seneste billede af 67P – selvom vi er nogle, som ikke er helt enige i APODs valg Wink – dette er så ok.

                  http://apod.nasa.gov/apod/ap141223.html

                  TOC Observatory - "http://tocobs.org -14.5″ – f:4,2 Newt - Atik383 - ZWO2600-mono – SXV H9 - QHY8L-color - SkyWatcher 80 mm ED refraktor - 60 mm F:6 apocromat - TAL Apolar 125 f : 7,5.

                  #126142

                  edbbob
                  Deltager
                    • Super Nova

                    Hold da op! Det billede er hele turen, de nedbidte negle og alle penge værd!

                    #126145

                    nightsky
                    Deltager
                      • Neutron star

                      Masser af nyt efter sidste uges AGU konference.

                      Pressekonference (1 time)
                      [TUBE]ISfa_l-Ji90[/TUBE]

                      http://blogs.esa.int/rosetta/2014/12/18/updates-from-agu/

                      Desuden er der masser af ballede med OSIRIS science teamet. Tilsyneladende har der
                      været massive problemer med instrumentet og af underlige grunde vil man ikke offentliggøre
                      de billeder man har. Som de eneste fik de stoppet streaming af billederne fra AUG mødet.
                      Åbenbart er der stadig vidensskabsfolk i Europa som mener befolkning (dem der betaler) ikke
                      er gode nok til at få data. De gamle dage fra ESA findes stadig.

                      Hvis man læser nedenstående kommentar (der er masser af guf), er man ikke i tvivl om at der
                      er masser af data som den forstokkede europæiske holdning til offentliggørelse holdes tilbage.
                      Der burde indføres samme regler som i USA, fri adgang til da for alle.

                      Having seen all the presentations that were actually shown, four are
                      still not viewable and
                      one was cancelled, I thought I would outline the
                      key things that were common conclusions.
                      A lot of results just defined
                      boundaries or the range of results and some did not match
                      existing
                      models or experimental data closely enough to give exact conclusions.
                      The majority
                      of the Philae reports amounted to a list of what data was
                      collected and how they might be
                      able to use it.

                      The Northern “Duckiesphere” currently in Summer is way more active
                      than the “Dark Side”.
                      The detection of metal ions like Sodium,
                      Magnesium, Zinc, Iron is limited to nighttime
                      observations and is
                      thought to be due to sputtering from the Solar Wind and Cosmic Rays.

                      They are not seen during the day, because cometary activity produces a
                      coma containing
                      gas, ions, charged particles and dust that physically
                      and magnetically shields the surface
                      from the Solar Wind.

                      Activity is directly correlated to the amount of sunlight incident on
                      a surface, but the neck
                      areas and the north polar plain are more active
                      than the head and body lobes due to a
                      thinner layer of insulation.
                      These more active areas contain fewer organics. The majority of
                      the
                      surface layer away from the active regions contains between 5 and 7%
                      organic
                      material, with the highest amounts on the sides of the lobes
                      where there is a lot more
                      exposed solid material. The nature of the
                      organics is still not known, one fit to the data
                      suggests a mixture of a
                      neutral black material with 99.5% Tholins and 0.5% Water. Another

                      result suggests that it is not all Tholins and is likely a mixture of
                      Carbon, Tholins, Low Iron
                      content silicate minerals and various
                      Sulphides.

                      The consensus seems to be that in the flatter plains where the
                      surface appears to be
                      covered in a dust blanket, like at the first
                      touchdown point, there is a top ice free layer of
                      friable, porous,
                      gravel and dust about 1cm thick made up of low iron minerals, silicates,

                      organics and Carbon. Below that the material starts to contain volatile
                      ices, the amount
                      increasing with depth. This mixed ice/dust/organics
                      layer varies, but is estimated to be 10
                      to 20cm normally, but may vary.
                      Beneath this is a hard layer of sintered ice/dust/organics,
                      which
                      although hard is also brittle as evidenced by the shards seen in the
                      ROLIS images.

                      Sulphur is present in significant amounts and is usually found in the
                      areas where Water is
                      coming from, but also from a few areas where very
                      little Water is seen. Although visually
                      the comet is pretty homogeneous,
                      chemically it seems not. Water tends to be produced in
                      very variable
                      amounts related to the time of day and position on the comet, whereas

                      Carbon Dioxide emission seems to be more constant. The ratio of CO2/H2O
                      is on average
                      about 7%. The thermal properties of the top dust layer
                      suggest up until now outgassing is
                      not coming from the harder sub
                      surface layer.

                      The CONSERT talk was limited and the second one cancelled, presumably
                      because Philae
                      has not been located. The data is clear and of good
                      quality, but the only conclusion is that
                      the shape of the signal peak
                      indicates very little or no scattering from internal surfaces,
                      meaning
                      the comet is not currently made up of metre or two sized planetesimals,
                      but is a
                      continuous solid.

                      Organics that have been identified include C2, C3, C4 compounds and
                      Benzene. Other
                      results indicate Amines, Benzoic Acids, Ketones and
                      Esters are probably present as well.
                      Dust particles from the comet are
                      larger than expected, but are very irregular,
                      conglomerates of very
                      loosely bound material which falls apart on contact. More solid grains

                      have been examined which although only micron size look like mini
                      comets, with planes,
                      pits and holes. They have also been seen to move
                      once trapped in the instrument. This
                      was explained as being their light
                      weight, but sublimating gas creating a frictionless layer
                      underneath
                      them likely helps.

                      The surface layer at Agilkia was revealed in all it glory by the
                      ROLIS images. Hopefully those
                      images will be available here soon. This
                      was the most informative and revealing
                      presentation shown. Analysis was
                      done of the particle sizes and the surface seems to be
                      made of a sort
                      of pea gravel 1 or 2 cm in size with larger pieces of broken cryorock
                      mixed
                      in. Hollows and depressions around a metre in size along with
                      small ledges and elevation
                      changes in the 10s of cm range. Little tiny
                      landslides of little pebbles, but little sign of dust
                      except at the base
                      of the 5m Cryobolder close to the touchdown point. It would appear
                      that
                      the surface layer material is very much like a type of aerogel, it
                      holds it shape perfectly
                      until disturbed and then just disintegrates
                      into a fine powder. This is what was seen in
                      both MIDAS and COSIMA.
                      Unfortunately the dust measuring device on Philae has so far only

                      registered 1 confirmed hit.

                      The team seem even more confident that Philae will survive and be
                      able to do more
                      science. It is clear from these presentations that there
                      is lots of revealing data available,
                      there are vast amounts of it and
                      much of it requires some new algorithms and models to
                      interpret,
                      especially the Philae data. An amazing job by everyone involved. I
                      should also
                      add that the speakers were way more entertaining and
                      interesting than many of the
                      others here.

                      So most of what we learned in the presentations that were shown, had
                      already been
                      deduced by ourselves or explained by team members here and
                      this just added confirmation
                      that many peoples combined educated guesses
                      were right. The talks showing OSIRIS data
                      and explanations of the comet
                      morphology were not streamed and information from the
                      plasma and
                      magnetic field experiments were not shown. Hopefully some sort of
                      apology or
                      explanation from the ESA team will be forthcoming to explain
                      this.


                      Philae’s view of “Perihelion Cliff” at its final resting place on the comet’s surface. Credits: ESA/Rosetta/Philae/CIVA

                      Og denne film Comet Watch

                      Nightsky2014-12-23 19:06:20

                      #126151

                      jens.jacobsen
                      Deltager
                        • Neutron star

                        Hejsa.

                        Inspirerende lille film, med den tumlende komet.

                        Det fik mig til at tjekke hvornår kometen igen ville være tilgængelig på vores nathimmel, og det viser sig at i januar-februar 2016 vil det være muligt at lave en lyskurve på kometen. Derved kan vi jo selv se om kometen stadig tumler på samme måde. Der skal nok en pæn kikkert, f.eks en 12″ eller mere til, da kometen er mag 14 på pågældende tidspunkt.

                        Nogen frivillige??

                        mvh
                        Jens

                        #134091

                        lindhard
                        Deltager
                          • Super Nova

                          Dsværre kniber det tilsyneladende med at vække Philae af frostdvalen selv om Sollyset nu er 10x stærkere end ved landingen.

                          LinkLindhard2015-06-13 20:14:42


                          mvh
                          Lars

                          #134103

                          norup
                          Deltager
                            • Super Giant
                            #134104

                            Torben Taustrup
                            Admin
                              • Neutron star

                              YES! Thumbs%20Up
                              Nu bliver det spændende at se, hvordan den vender – og om de kan lokalisere den.

                              TOC Observatory - "http://tocobs.org -14.5″ – f:4,2 Newt - Atik383 - ZWO2600-mono – SXV H9 - QHY8L-color - SkyWatcher 80 mm ED refraktor - 60 mm F:6 apocromat - TAL Apolar 125 f : 7,5.

                              #134106

                              nightsky
                              Deltager
                                • Neutron star

                                “Philae is doing very well: It has an operating temperature of -35ºC and
                                has 24 Watts
                                available,” explains DLR Philae Project Manager Dr.
                                Stephan Ulamec. “The lander is ready
                                for operations.”

                                Sikke en god nyhed.

                                http://www.esa.int/Our_Activities/Space_Science/Rosetta/Rosetta_s_lander_Philae_wakes_up_from_hibernation

                                http://www.independent.co.uk/news/science/rosetta-mission-philae-comet-lander-wakes-and-contacts-earth-10318822.html

                                #134107

                                Torben Taustrup
                                Admin
                                  • Neutron star

                                  “Philae phone home” Wink

                                  TOC Observatory - "http://tocobs.org -14.5″ – f:4,2 Newt - Atik383 - ZWO2600-mono – SXV H9 - QHY8L-color - SkyWatcher 80 mm ED refraktor - 60 mm F:6 apocromat - TAL Apolar 125 f : 7,5.

                                Viser 15 indlæg - 196 til 210 (af 219 i alt)
                                • Emnet 'Rosetta i fin form' er lukket for nye svar.