Les plantes sont des organismes sensibles qui communiquent à l'aide d'ultrason!!

Une étude fascinante sur la communication chez les végétaux: gracieuseté de l'Université d'Oxford....

Article au complet
Source:
http://beheco.oxfordjournals.org/content/24/4/789.full




Figure 1

A putative model of a mechanism underlying sound production in plants. Plant cells vibrate as a result of the active movement of organelles within the cell (i.e., cytoplasmic streaming; orange arrows in panel B). Cytoplasmic streaming is caused by the activity of motor protein myosins as they slide along actin filaments using the hydrolysis energy of adenosine triphosphate (panel C). As the nanomechanical motion generated within a cell reflects the unique metabolic status of that cell, this information is contained in the emitted vibrational wave. Vibrations from individual cells propagate through the medium as sound waves and reach neighboring cells; if the receiving cells are receptive to that particular frequency, they will also start vibrating proportionally to the intensity of the received signal and when all the cells are “in tune,” the signal is amplified (panel D). As the signal extends outside the leaf or root of the plant, it conveys information about that plant to neighboring plants or other organism (panel A).

In conclusion, a considerable body of evidence emerging from contemporary research in the plant sciences is increasingly recognizing plants as highly sensitive organisms that perceive, assess, interact, and even facilitate each other by actively acquiring information from their environment (Karban 2008; Baluška 2009; Trewavas 2009). We now know, for example, that when attacked, plants “cry for help” by producing volatiles that attract carnivorous enemies of the attacking herbivores (Dicke 2009); and on the other hand, parasitic plants can recognize their prey at a distance and evaluate their nutritional value before deciding to invade them (Kelly 1992; Koch et al. 2004). Considering that these are only a very few examples of what plants do, the Aristotelian view of plants as automata-like passive and insensitive creatures seems to be no longer accurate. By relinquishing this out-of-date view of the plant world, I hope the ideas and questions presented here seduce the most enquiring aspect of our nature into exploring the world of plants in its full potential complexity.

La terre tremble

Tremblement de terre des derniers jours
Source:
http://www.iris.edu/seismon/
http://www.emsc-csem.org/Earthquake/seismologist.php

Météorite aperçu au Québec

Une boule de feu a été aperçue au-dessus de la Baie-des-Chaleurs, tôt mardi matin. Elle aurait aussi été vue au Saguenay, en Nouvelle-Écosse et au Nouveau-Brunswick.

Environ 20 personnes ont rapporté le phénomène à la Sûreté du Québec (SQ), un peu après 4 h, selon Claude Doiron, porte-parole de la SQ pour le district du Bas-Saint-Laurent-Gaspésie-Îles-de-la-Madeleine.
Plusieurs habitants de la Baie-des-Chaleurs qui vivent près de la ville de Chandler ont affirmé avoir vu une boule lumineuse traverser le ciel, suivi d'une forte détonation.  Des citoyens auraient même senti leur maison trembler et affirmé que tout le village a été éclairé comme en plein jour, le temps de quelques secondes.
Dans le secteur de St-Edgar, il y aurait eu une baisse de tension électrique au moment du passage de la météorite.
Des policiers en poste à New Richmond sont sortis après la détonation, pensant assister à l'écrasement d'un avion.
«Lorsque le phénomène s'est produit à 4 h 5 ce matin, nos policiers ont été témoins du phénomène. Même un de nos postes dans la Baie-des-Chaleurs en a vibré, a affirmé Claude Doiron. Il est fréquent d'apercevoir des météores dans la région, mais celui-ci semble être tombé très près des régions habitées», a déclaré Claude Doiron.
Bien que la boule de feu ne semble avoir fait aucun dommage ou de point de chute au sol pour l'instant, la Gendarmerie royale du Canada va mener une enquête.
Vue en Nouvelle-Écosse et au Nouveau-Brunswick
Le phénomène a aussi été aperçu en Nouvelle-Écosse et au Nouveau-Brunswick. Steve Betts, a indiqué sur Twitter qu'il conduisait vers l'aéroport d'Halifax, lorsqu'à 5 h 7, il a vu «quelque chose qui tombait du ciel en flammes».
«Cela a laissé une traînée de feu dans le ciel, puis c'est devenu vert et cela a disparu. Je présume qu'il ne s'agit pas d'un avion, alors c'est peut-être un météorite?», a-t-il écrit.
Jan Fletcher a aussi écrit sur Twitter qu'il avait vu quelque chose de semblable. «Je me suis réveillé et j'ai vu une boule de feu qui tombait du ciel dans une zone près du lac. Est-ce un météorite?» Il a précisé plus tard : «La boule de feu que j'ai aperçue ce matin a aussi été vue par une personne à Northumberland et une autre à Truro. C'est sûrement un météorite».
Un dénommé Danny a aussi rapporté sur Twitter qu'il avait vu «une lumière vive suivie d'une boule de feu», aux alentours de 5 h 10 près de l'aéroport de Moncton au Nouveau-Brunswick.
 Source:
http://tvanouvelles.ca/lcn/infos/regional/estduquebec/archives/2014/03/20140318-102954.html
http://www.lapresse.ca/sciences/astronomie-et-espace/201403/18/01-4748956-un-meteore-apercu-dans-les-maritimes-et-en-gaspesie.php

3 Nuclear events in 24h

ISON still alive

COMET ISON LIVES (UPDATED): Cancel the funeral. Comet ISON is back from the dead. Yesterday, Nov. 28th, Comet ISON flew through the sun's atmosphere and appeared to disintegrate before the cameras of several NASA and ESA spacecraft. This prompted reports of the comet's demise. Today, the comet has revived and is rapidly brightening. Click to view a SOHO coronagraph movie of the solar flyby (updated Nov. 29 @ 1800 UT):

Before the flyby, experts had made many predictions about what might happen to the comet, ranging from utter disintegration to glorious survival. No one predicted both.

Karl Battams of NASA's Comet ISON Observing Campaign says, "[colleague] Matthew Knight and I are ripping our hair out right now as we know that so many people in the public, the media and in science teams want to know what's happened. We'd love to know that too! Right now, here's our working hypothesis:

"As comet ISON plunged towards to the Sun, it began to fall apart, losing not giant fragments but at least a lot of reasonably sized chunks. There's evidence of very large dust in the long thin tail we saw in the [SOHO coronagraph] images. Then, as ISON plunged through the corona, it continued to fall apart and vaporize, losing its coma and tail completely just like sungrazing Comet Lovejoy did in 2011. What emerged from the Sun was a small but perhaps somewhat coherent nucleus that has resumed emitting dust and gas for at least the time being."
Battams emphasizes that it is too soon to tell how big the remnant nucleus is or how bright the resurgent comet will ultimately become. "We have a whole new set of unknowns, and this ridiculous, crazy, dynamic and unpredictable object continues to amaze, astound and confuse us to no end. We ask that you please be patient with us for a couple of days as we analyze the data and try to work out what is happening."
Astrophotographer Babak Tafreshi has edited an HD video that compares views of ISON from both of SOHO's coronagraphs. "It seems the comet could become a naked eye object with several degrees of scattered tail by Dec 2nd or 3rd," he predicts. "It's not the comet of the century for sure, and fainter than the Lovejoy sungrazer in Dec. 2011, but an interesting imaging target is just a few nights away!" Solar flare alerts: text, voice

Source:
http://www.spaceweather.com/ 

Small meteor fragment falls into the Ionian Sea

28/ 11/ 2013

ANA-MPA -- A small meteor fragment hit the earth's atmosphere over the Ionian Sea in northwest Greece on Wednesday night, blazing across the sky as it burned up and alarming the people on the islands of Cephalonia and Zakynthos where the phenomenon was most visible, as well as in the western cities of Ioannina and Patras. No injuries or damage were reported.

 People who witnessed the meteor fall into the sea reported a bright light across the sky and a loud thundering sound at approximately 21:30 on Wednesday night. 

Academy of Athens Astronomy Research Center Director Panos Patsis told ANA-MPA that “rocks fall from the sky all the time”, noting that such phenomena are not unusual and most likely it was a small meteor or a fragment of a comet with a diameter of less than a meter. He said that most of the time they go unnoticed because they end up in the sea or in remote unpopulated areas on the Earth. 

Eugenides Foundation Planetarium Director Dionissis Simopoulos noted that more than 100 tons of meteors fall on the earth's surface everyday. He said that the meteor piece that fell last night couldn't be larger than a human head in size and probably weighed approximately two-and-a-half kilos. 

Both ruled out the likelihood that it was a fragment of ISON, the so-called comet of the century, which is expected to graze the surface of the Sun on Thursday night. They also said that there is a small likelihood it was a leftover from the Leonid Meteor Shower, as the phenomenon had culminated earlier in the month.



(file photo)

Μore on subscrider' s page | application

 

 

Source:

http://www.amna.gr/english/articleview.php?id=4367

ISON News

CANCEL THE EULOGY ... FOR NOW: Comet ISON flew through the sun's atmosphere on Nov. 28th and the encounter did not go well for the icy comet. Just before perihelion (closest approach to the sun) the comet rapidly faded and appeared to disintegrate. This prompted reports of ISON's demise. However, a fraction of the comet might have survived. Click on the image below to see what emerged from Comet ISON's brush with solar fire:

In the movie, Comet ISON seems to be falling apart as it approaches the sun. Indeed, researchers working with NASA's Solar Dynamics Observatory said they saw nothing along the track that ISON was expected to follow through the sun's atmosphere. Nevertheless, something has emerged. Whether this is a small scorched fragment of Comet ISON's nucleus or perhaps a "headless comet"--a stream of debris marking the remains of the comet's disintegrated core--remains to be seen.

An earlier movie from SOHO shows more of the comet's approach:

The movie spans a day and a half period from Nov. 27th (01:41 UT) to 28th (15:22 UT). We see that Comet ISON brightened dramatically on Nov. 27th before fading on Nov. 28th. That brightening might have been a disintegration event, in which the comet cracked open and spilled its vaporizing contents into space.

In summary, we still don't know for sure what has happened to Comet ISON. Stay tuned for updates as more data arrive from NASA's fleet of solar observatories. Solar flare alerts: text, voice

Source:

http://www.spaceweather.com/