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"What would an imaginary terrestrial observer see as the Sun runs out of hydrogen in the future?"
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Seminar Detail
Stromatolites: What's Sulfur Got to Do With It?
Presenter: Janet Siefert ()
April 8, 2008 02:30 PM Pacific
Stromatolites (or more generally, microbialites) are carbonate encased complex microbial communities. They were a mainstream feature of early earth and now are found only in special ecosystems that provide for bacterial domination. This talk describes the bacterial constituency and metabolism within the local context of extant microbialites. We provide evidence that at least one of the conditions for microbialite formation is the presence of sulfur cycle resident in the community. Descriptions such as these better define possible early earth conditions that proved ripe for stromatolite formation and the possibility that we might extend those constraints to the possibilities of similar biotic preservation extra terrestrially.
Participation Instructions
With a Polycom....RSVP to Marco Boldt (Marco.Boldt@nasa.gov) and connect to WebEx as instructed below. If you need Polycom help during the live event, message Marco Boldt in WebEx.
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Without a Polycom...There are two ways to participate:
1) You can listen to the seminar on the telephone while viewing the slides in WebEx (see WebEx instructions above). The NASA conference phone number will be displayed when joining the WebEx meeting.
2) You can watch the Realplayer webcast at: http://vanseg-1.arc.nasa.gov/2008/AB080408-01.ram and view the slides in WebEx (see WebEx instructions above) There is a 30 second delay for the webcast, so you will need to control the slides manually using the arrow buttons in WebEx. Questions for the speaker can be posted in the WebEx chat area to be answered at the end of the talk. Do not try to watch the Realplayer webcast at the same time as the Polycom or the phone.December 21, 2007