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HD-189733b-1.jpgExtra-Solar Planet HD 189733b74 visiteNASA's Hubble Space Telescope (HST) has made the first detection ever of an organic molecule in the atmosphere of a Jupiter-sized planet orbiting another star. This breakthrough is an important step in eventually identifying signs of life on a planet outside our Solar System.
The molecule found by Hubble is Methane, which under the right circumstances can play a key role in prebiotic chemistry the chemical reactions considered necessary to form life as we know it.
This discovery proves that Hubble and upcoming space missions, such as NASA's James Webb Space Telescope, can detect organic molecules on planets around other stars by using spectroscopy, which splits light into its components to reveal the "fingerprints" of various chemicals.
"This is a crucial stepping stone to eventually characterizing prebiotic molecules on planets where life could exist," said Mark Swain of NASA's Jet Propulsion Laboratory (JPL), Pasadena, Calif., who led the team that made the discovery. Swain is lead author of a paper appearing in the March 20 (2008) issue of Nature.
The discovery comes after extensive observations made in May 2007 with Hubble's Near Infrared Camera and Multi-Object Spectrometer (NICMOS). It also confirms the existence of water molecules in the planet's atmosphere, a discovery made originally by NASA's Spitzer Space Telescope in 2007. "With this observation there is no question whether there is water or not water is present", said Swain.
The planet now known to have Methane and water is located 63 Light-Years away in the constellation Vulpecula. Called HD 189733b, the planet is so massive and so hot it is considered an unlikely host for life. HD 189733b, dubbed a "hot Jupiter", is so close to its parent star it takes just over two days to complete an orbit. These objects are the size of Jupiter but orbit closer to their stars than the tiny innermost planet Mercury in our solar system.
HD 189733b's atmosphere swelters at 1700 degrees Fahrenheit, about the same temperature as the melting point of Silver.
Though the star-hugger planet is too hot for life as we know it, "this observation is proof that spectroscopy can eventually be done on a cooler and potentially habitable Earth-sized planet orbiting a dimmer red dwarftype star," Swain said. The ultimate goal of studies like these is to identify prebiotic molecules in the atmospheres of planets in the "habitable zones" around other stars, where temperatures are right for water to remain liquid rather than freeze or evaporate away.
The observations were made as the planet HD 189733b passed in front of its parent star in what astronomers call a transit. As the light from the star passed briefly through the atmosphere along the edge of the planet, the gases in the atmosphere imprinted their unique signatures on the starlight from the star HD 189733.
The astronomers were surprised to find that the planet has more Methane than predicted by conventional models for "hot Jupiters".
"This indicates we don't really understand exoplanet atmospheres yet," said Swain. "These measurements are an important step to our ultimate goal of determining the conditions, such as temperature, pressure, winds, clouds, etc., and the chemistry on planets where life could exist. Infrared spectroscopy is really the key to these studies because it is best matched to detecting molecules", said Swain.
Swain's co-authors on the paper include Gautam Vasisht of JPL and Giovanna Tinetti of University College, London/European Space Agency.MareKromium
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NGC-3372-B.jpgNGC 3372 - The Dark Clouds of the Carina Nebula74 visite"...Quoties inter homines fui, minor homo redii..."
(Seneca)
"...Ogni volta che fui in mezzo agli uomini, mi ritrovai diminuito (come uomo)..." (ovvero: più si sta in mezzo ai tumulti del - cosiddetto - "vivere civile", e peggio si diventa)MareKromium
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SNR-1006.jpgSupernova Remnant SNR-100674 visite"...Ea Natura multitudinis est: aut servit humiliter, aut superbe dominatur; Libertatem, quae media est, nec sibi parare modice, nec habere sciunt..."
(Livio)
"...La folla ha questa Natura: o serve umilmente, o comanda con arroganza; né essa sa gestire un'equa misura di Libertà, né, nella sua pienezza, sa goderne..."MareKromium
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NGC-6888~0.jpgNGC 6888: The "Crescent Nebula"74 visite"...Dunque lo Spirito non è Molteplicità, non è parte di un Tutto in sé Molteplice, giacché non potrebbe appartenere ad un Tutto Molteplice senza essere in se stesso, intrinsecamente, molteplice.
Così che la negazione della molteplicità intrinseca potrebbe bastare a chiarire d'assurdo il concetto dello Spirito parte di una molteplicità..."
G. Gentile, "Teoria Generale dello Spirito come Atto Puro"MareKromium
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NGC-6357.jpgPismis 24: Open Star Cluster74 visite"...The unfolding of your words gives Light; it imparts understanding to the simple..."
- Psalm 119:130MareKromium
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Alpha_centauri_size.pngStar-Size!74 visite"Beato è quei che in Libertà sicura
Povero ma contento i giorni mena,
E che fuor di Speranza e fuor di Pena
Pompe non cerca e Dignità non cura"
(Fulvio Testi)MareKromium
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Omega_Centauri-HST.jpgThe Center of Omega Centauri74 visite"...Feliciter sapit qui periculo alieno sapit..."
(Binder)
"...Realmente saggio colui che apprende dall'esperienza altrui..." (trad. libera)MareKromium
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NGC-7380-PIA12868.jpgNGC 7380 - The "Wizard Nebula"74 visiteIn my rear view mirror, the Sun is going down
Sinking behind bridges in the road...
And I think of all the good things
That we have left undone,
And I suffer premonitions
Confirm suspicions
Of the holocaust to come...
The wire that holds the cork
That keeps the anger in
Gives way,
And suddenly its day again.
The Sun is in the East
Even though the day is done...
Two Suns in the Sunset,
Could be the human race is run?
Like the moment when your brakes lock,
And you slide toward the big truck,
And stretch the frozen moments with your fear...
And youll never hear their voices,
And youll never see their faces,
You have no recourse to the law anymore...
And as the windshield melts
My tears evaporate,
Leaving only charcoal to defend
Finally I understand
The feelings of the few,
Ashes and diamonds
Foe and friend
We were all equal in the end...
Pink Floyd - "Two Suns in the Sunset"MareKromium
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PSR_B1509-58.jpgPulsar B1509-58 74 visite"...There are several kinds of stories, but only one is the really difficult kind: the humorous..."
Mark Twain (1835 - 1910)MareKromium
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Stephan_s_Quintet-PIA04201_modest.jpgGalaxy Group "Stephan's Quintet"73 visite"...Ho visto una lumaca scivolare...
Lungo il filo...
Di un rasoio.
Ecco il mio sogno.
Il mio incubo.
Scivolare...Strisciare...
Lungo il filo...
Di un rasoio.
E sopravvivere".
Dal film "Apocalypse Now"
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NGC-4565-2.jpgNGC 4565 - The "Needle" Galaxy73 visite"...Quod mirabile est, delectabile est..."
(Aristotele)
"...Ciò che provoca meraviglia, provoca piacere..."
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RY-Tau_gemini_f.jpgRY Tauri73 visite"...Lear si ribellava senza risparmiarsi contro l'arbitrio fatto Legge di coloro che esercitavano il diritto del più forte, per ritirarsi, deluso e sconcertato, quando gli stessi uomini al cui fianco si era posto per cercarne il riscatto, diventavano i nuovi tiranni contro cui combattere...
E così, la voglia di Verità e di Onestà un po' alla volta lo allontanarono da quegli uomini stupidi e violenti, avvicinandolo sempre più a quel piccolo punto luminoso il cui fascino, in fondo, stava nell'enorme distanza che lo separava da quel mondo falso e violento al quale lui non voleva più appartenere.
Una Stella lontana, a cui chiedere asilo per non assistere allo scempio che l'uomo stava compiendo di se stesso.
Un luogo dove poter vivere in armonia con il Creato e con Dio.
Viaggiò tra i Sistemi Solari con questa speranza, ma comprese troppo tardi che l'isola che cercava era già dentro di lui..."
G. Spina - "Una Sera attorno al Fuoco"
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