Messenger-Mission / Merkur

[Peter5]

Bestens!

[karmaka]

Da sage noch einer auf dem Merkur gibt es nichts zu sehen!

Hier die exotische Realität:

Al-Hamadhanis kraterbreites Smiley-Gesicht,

eine planetare Begräbnisstätte eines Asteroiden

und zwei lava-verhüllte Geisterkrater.

Al-Hamadhanis kraterbreites Smiley-Gesicht:
http://messenger.jhuapl.edu/gallery/sciencePhotos/pics/EW0211589984G.nomap.png
(Der Al-Hamadhani Krater)

Die planetare Begräbnisstätte:
http://messenger.jhuapl.edu/gallery/sciencePhotos/pics/171577.png
(Der Krater ist übrigens noch unbenannt. Welchen Namen würdet ihr ihm denn geben? Die sich kreuzenden
Kraterlinien stammen von den Ejekta zweier anderer Krater, die nicht im Bild zu sehen sind.)

Die Geisterkrater:
http://messenger.jhuapl.edu/gallery/sciencePhotos/pics/EW0209895822L_65370.map.png

Hier gibt es die anderen aktuellen Messenger-Merkurbilder: http://messenger.jhuapl.edu/gallery/sciencePhotos/view.php?gallery_id=2&page=1&bydate=2011-04

 

Martin

[Mettmann]

Welchen Namen würdet ihr ihm denn geben?

Bad Kohlgrub.

[karmaka]

Am 30.9.11 wurden neue interessante Analyseergebnisse der MESSENGER-Mission
in der Zeitschrift SCIENCE veröffentlicht. Hier eine Zusammenfassung:

http://www.space.com/13127-planet-mercury-revealed-nasa-messenger-spacecraft.html

Teil 1: http://www.zeit.de/wissen/2011-09/merkur-messenger-mission
Teil 2: http://www.zeit.de/wissen/2011-09/merkur-messenger-mission/seite-2

Mehr zu den 'Blue Hollows' gibt es hier:

http://www.jgr-apolda.eu/index.php?topic=6801.15

 

Martin

[boborit]

Hi Martin,

sehr interessant!!

Ist eigentlich schon ein Buch zu der Mission erschienen?

Grüße - Michael

[karmaka]

Ist eigentlich schon ein Buch zu der Mission erschienen?

Ich habe nur dieses aus dem Jahre 2008 gefunden:

http://www.amazon.com/MESSENGER-Mission-Mercury-D-L-Domingue/dp/0387772111/ref=sr_1_2?ie=UTF8&qid=1317646214&sr=8-2

 

Martin

[karmaka]

Die Ergebnisse der ersten sechs Monate der Messenger-Mission gibt es hier ganz frisch vom
"joint meeting of the European Planetary Science Congress and
the Division for Planetary Sciences of the American Astronomical Society" in Nantes:

http://www.physorg.com/news/2011-10-messengerresults-months-orbit.html

30 papers und posters:

oral program: http://meetingorganizer.copernicus.org/EPSC-DPS2011/oral_program/8295

poster program: http://meetingorganizer.copernicus.org/EPSC-DPS2011/poster_program/8295

 

Martin

[karmaka]

99,9 % Merkur

Für eure 'kraterliebenden Augen' hier nun die vielleicht bisher
vollständigste hochauflösende Karte der Oberfläche des Merkurs:

http://messenger.jhuapl.edu/gallery/sciencePhotos/pics/2011-10-28_global_view_MESSENGER.png

http://messenger.jhuapl.edu/gallery/sciencePhotos/image.php?gallery_id=2&image_id=681

vergrößern ... und genießen!  

 

Martin

[boborit]

Danke Martin

schön, das es hier noch seriöses Themen gibt...

Michael

[karmaka]

Die Messenger-Mission wurde um ein weiteres Jahr verlängert:

http://www.nasa.gov/mission_pages/messenger/media/MissionExtends.html

[karmaka]

Neue Erkenntnisse über den Merkur nach einem Jahr Forschung:

http://www.sterne-und-weltraum.de/alias/planetenforschung/merkur-war-lange-geologisch-aktiv/1146435

[karmaka]

“In the future everyone will be famous for fifteen minutes” Andy Warhol (1928 – 1987)

15 Minuten FAME für den Warhol-Krater bitte  

http://messenger.jhuapl.edu/gallery/sciencePhotos/pics/Warhol_EW0227644290I_RGB_popart.png

http://messenger.jhuapl.edu/gallery/sciencePhotos/image.php?gallery_id=2&image_id=836

Hier sind auch die anderen neuen Namensgeber der Merkurkrater:

http://solarsystem.nasa.gov/news/display.cfm?Print=1&News_ID=39583&FIELDNAMES=

 

[karmaka]

Neues über die Oberflächenbeschaffenheit des Merkur

http://www.agu.org/news/press/jhighlight_archives/2012/2012-09-17.shtml#one

In general, the measurements show that Mercury’s surface composition is very different from that of other planets in the solar system. It is dominated by minerals high in magnesium and enriched in sulfur. This composition is similar to that expected from partial melts of enstatite chondrites, a rare type of meteorite that formed at high temperatures in highly reducing (low oxygen) conditions in the inner solar system.

Chemical heterogeneity on Mercury's surface revealed by the MESSENGER X-Ray Spectrometer Journal of Geophysical Research-Planets,

http://www.agu.org/pubs/crossref/pip/2012JE004153.shtml

We present the analysis of 205 spatially resolved measurements of the surface composition of Mercury from MESSENGER's X-Ray Spectrometer. The surface footprints of these measurements are categorized according to geological terrain. Northern smooth plains deposits and the plains interior to the Caloris basin differ compositionally from older terrain on Mercury. The older terrain generally has higher Mg/Si, S/Si, and Ca/Si ratios, and a lower Al/Si ratio than the smooth plains. Mercury's surface mineralogy is likely dominated by high-Mg mafic minerals (e.g., enstatite), plagioclase feldspar, and lesser amounts of Ca, Mg, and/or Fe sulfides (e.g., oldhamite). The compositional difference between the volcanic smooth plains and the older terrain reflects different abundances of these minerals and points to the crystallization of the smooth plains from a more chemically evolved magma source. High-degree partial melts of enstatite chondrite material provide a generally good compositional and mineralogical match for much of the surface of Mercury. An exception is Fe, for which the low surface abundance on Mercury is still higher than that of melts from enstatite chondrites and may indicate an exogenous contribution from meteoroid impacts.

 

Martin

[karmaka]

Mercury May Have Harbored an Ancient Magma Ocean: Massive Lava Flows May Have Given Rise to Two Distinct Rock Types

http://web.mit.edu/press/2012/mercury-may-have-harbored-ancient-magma-ocean.html

Bernard Charlier, Timothy L. Grove, Maria T. Zuber.
Phase equilibria of ultramafic compositions on Mercury and the origin of the compositional dichotomy. Earth and Planetary Science Letters, 2013; 363: 50 DOI

http://www.sciencedirect.com/science/article/pii/S0012821X12007078

Abstract

Measurements of major element ratios obtained by the MESSENGER spacecraft using x-ray fluorescence spectra are used to calculate absolute element abundances of lavas at the surface of Mercury. We discuss calculation methods and assumptions that take into account the distribution of major elements between silicate, metal, and sulfide components and the potential occurrence of sulfide minerals under reduced conditions. These first compositional data, which represent large areas of mixed high-reflectance volcanic plains and low-reflectance materials and do not include the northern volcanic plains, share common silica- and magnesium-rich characteristics. They are most similar to terrestrial volcanic rocks known as basaltic komatiites. Two compositional groups are distinguished by the presence or absence of a clinopyroxene component. Melting experiments at one atmosphere on the average compositions of each of the two groups constrain the potential mineralogy at Mercury's surface, which should be dominated by orthopyroxene (protoenstatite and orthoenstatite), plagioclase, minor olivine if any, clinopyroxene (augite), and tridymite. The two compositional groups cannot be related to each other by any fractional crystallization process, suggesting differentiated source compositions for the two components and implying multi-stage differentiation and remelting processes for Mercury. Comparison with high-pressure phase equilibria supports partial melting at pressure <10 kbar, in agreement with last equilibration of the melts close to the crust–mantle boundary with two different mantle lithologies (harzburgite and lherzolite). Magma ocean crystallization followed by adiabatic decompression of mantle layers during cumulate overturn and/or convection would have produced adequate conditions to explain surface compositions. The surface of Mercury is not an unmodified quenched crust of primordial bulk planetary composition. Ultramafic lavas from Mercury have high liquidus temperatures (1450–1350 °C) and very low viscosities, in accordance with the eruption style characterized by flooding of pre-existing impact craters by lava and absence of central volcanoes.

[karmaka]

Offiziell läuft die erweiterte MESSENGER-Mission in diesem Monat aus, falls nicht doch noch letztmalig eine Verlängerung
für zwei weitere Jahre genehmigt wird.

MESSENGER hat im Februar 2013 die Arbeit an der ersten kompletten Karte des Merkurs beendet:

VIDEO-LINK

FOTO-LINK