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They were able to compare the ticking rates of two optical clocks separated by 2000 km, with the objective of computing sea level based on the effect gravity has on the clock ticking rate. They did the experiment using glass optical fibers, but I wonder if we could one day do the same from orbit, to measure the gravitational field around Earth.

isn't this is effectively what pacome has been doing with his time for the last few years? e.g. http://arxiv.org/pdf/1308.6766v1.pdf also mentioning the ACES experiment

nice movie

At the link below you find additional information about the projects: Education: Ten weeks to save the world http://www.nature.com/news/2010/100915/full/467266a.html

well, most good ideas probably take only a second to be formulated, it's the details that take years :-)

I do not think the point of the SU is to formulate new ideas (infact there is nothing new in the projects chosen). Their mission is to build and maintain a network of contacts among who they believe will be the 'future leaders' of space ... very similar to our beloved ISU.

Here we go: we might not need liquid water after all on mars to get some nice flowering plants there! ... and terraform ? :-) Thirsty plants can extract water from the crystalline structure of gypsum, a rock-forming mineral found in soil on Earth and Mars.

Some plants grow on gypsum outcrops and remain active even during dry summer months, despite having shallow roots that cannot reach the water table. Sara Palacio of the Pyrenean Institute of Ecology in Jaca, Spain, and her colleagues compared the isotopic composition of sap from one such plant, called Helianthemum squamatum (pictured), with gypsum crystallization water and water found free in the soil. The team found that up to 90% of the plant's summer water supply came from gypsum.

The study has implications for the search for life in extreme environments on this planet and others.

Nature Commun 5, 4660 (2014)

Very interesting indeed. Attention is to be put on the form of calcium sulfate that is found on Mars. If it is hydrated (gypsum Ca(SO4)*2(H2O)) it works, but if it is dehydrated there is no water for the roots to take in. The Curiosity Rover tries to find out, but has uncertainty in recognising the hydrogen presence in the mineral: Copying : "(...) 3.2 Hydration state of calcium sulfates Calcium sulfates occur as a non-hydrated phase (anhydrite, CaSO4) or as one of two hydrated phases (bassanite, CaSO4.1/2H2O, which can contain a somewhat variable water content, and gypsum, CaSO4.2H2O). ChemCam identifies the presence of hydrogen at 656 nm, as already found in soils and dust [Meslin et al., 2013] and within fluvial conglomerates [Williams et al., 2013]. However, the quantification of H is strongly affected by matrix effects [Schröder et al., 2013], i.e. effects including major or even minor element chemistry, optical and mechanical properties, that can result in variations of emission lines unrelated to actual quantitative variations of the element in question in the sample. Due to these effects, discriminating between bassanite and gypsum is difficult. (...)"

forgot the reference http://www.msl-chemcam.com/doc/documents/577/Nachon%20et%20al%20Calcium%20sulfate%20veins%20characterized%20by%20ChemCam%20Curiosity%20at%20Gale%20Crater%20Mars_2013.pdf

Open questions in geoscience. Food for thought

ooops ....

Where is the sticker saying "if found, please post this item unstamped to the following address"?

Yup, it's ours... Still, better take it out of the river than in the face. Such a big one especially.

"A new lightweight, energy-efficient tool for analyzing a material's chemical makeup could improve the detection abilities of various technologies, ranging from bomb-detecting drones to space rovers searching for signs of life". Raman Spectroscopy is about measuring vibrational modes in molecules. This vibrational modes are in the meV typically, turning Raman Spectroscopy into a high precision technique. This impressive work shows a new technique based on the use of optical fibers coupled to photomultipliers allowing its use, author's word, in extreme conditions such as unmanned aircraft vehicles (UAVs) and Mars/Moon rovers.

A 60-year-old theory about the structure of the magnetic fields that surround Earth has been confirmed directly for the first time. The lead author of the paper is an undergraduate student who invented a way to view the Earth's magnetosphere in three dimensions.

I doubt that Shnoll is really the first one making such experiments, but perhaps they are more complete than any others done before. Similar things are very popular in the context of Psychology and more exotic fields. If I remember correctly someone ran long experiments with random number generators... Mostly the stories died after a short time, since the experiments are not reproducable. Anyway, why do these guys always have to claim that their work is somehow fundamentally changing our view of physics, notoriously referring to Einstein-Bohr debates and this stuff. That's nonsense! If these effects exist the first explanation is always much simpler. There is somewhere something that influences physics on Earth in a defined way. But this influence depends on the relative position or whatever of the Earth to that whatever-it-is. No problem with absolute time and all that sh...

Two years ago, nearly unnoticed in the West, the Russian biophysicist S.E. Shnoll published a paper in the prominent Russian physics journal Uspekhi Fisicheskikh Nauk ..... ah then ...

You are right, Leo, they are mostly Russians that publish in some unspellable Journals nobody knows.... or then they are supported by Templeton Foundation.

Time reversed waves to detect defects in materials and earth quakes

Let's start betting which party Aliens vote: GREEN, BLUE, RED, BLACK?

http://astrobiology.nasa.gov/ for the moment is down. My bet, the microbe they found notified its cousins and they are currently invading the US

you can still see the rest of it here: http://www.nasa.gov/multimedia/nasatv/index.html a good link with a summary and discussion on the announcement is here: http://www.guardian.co.uk/science/2010/dec/02/nasa-life-form-bacteria-arsenic

Just in case you missed these one... should be of interest for ACT's climate modelling squad. "As well as telling us more about Venus, it could be sending a warning to those on Earth seeking to inject our atmosphere with sulphur droplets in an attempt to mitigate climate change."