https://exastra.blog/2020/01/02/giovannona-coscialunga/https://exastra.blog/wp-content/uploads/2020/01/m79-arma.jpgm79-armahttps://exastra.blog/wp-content/uploads/2020/01/m33-arma.jpgm33-armahttps://exastra.blog/wp-content/uploads/2020/01/io-arma.jpgio-armahttps://exastra.blog/wp-content/uploads/2020/01/startan-arma.jpgstartan-armahttps://exastra.blog/wp-content/uploads/2020/01/quarzo.jpgquarzohttps://exastra.blog/wp-content/uploads/2020/01/arma.jpgarma2020-12-26T09:54:10+00:00monthlyhttps://exastra.blog/2017/08/03/che-fa-batti/https://exastra.blog/wp-content/uploads/2017/08/spettro-castore.jpgspettro-castorehttps://exastra.blog/wp-content/uploads/2017/07/ngc7293_2004.jpgIDL TIFF fileIDL TIFF filehttps://exastra.blog/wp-content/uploads/2017/07/m57-spettro-ed-immagine1.jpgm57 spettro ed immaginehttps://exastra.blog/wp-content/uploads/2017/07/composizione-nebulose-planetarie.jpgcomposizione nebulose planetariehttps://exastra.blog/wp-content/uploads/2017/07/astronomik_uhc_2-inch.jpgAstronomik_UHC_2-InchFiltro visuale UHChttps://exastra.blog/wp-content/uploads/2017/07/astronomik_oiii_2-inch.jpgAstronomik_OIII_2-InchFiltro visuale [OIII]https://exastra.blog/wp-content/uploads/2017/07/curva-di-trasmissione-oiii2.jpgCurva-di-trasmissione OIIIGrafico della trasissività del filtro [OIII]. Si noti come quasi il 100% della luce lasciata passare sia attorno alle linee di emissione dell'[OIII]https://exastra.blog/wp-content/uploads/2017/07/curva-di-trasmissione-uhc.jpgCurva-di-trasmissione UHCGrafico della trasissività del filtro UHC. Si noti come quasi il 100% della luce lasciata passare sia attorno alle linee di emissione dell'[OIII] e dell'idrogeno (H-alpha)https://exastra.blog/wp-content/uploads/2017/07/m57-spettro-ed-immagine.jpgm57 spettro ed immaginehttps://exastra.blog/wp-content/uploads/2017/07/spettro-m761.jpgspettro M762017-08-07T09:49:41+00:00monthlyhttps://exastra.blog/2017/04/25/voyeur/https://exastra.blog/wp-content/uploads/2017/04/rigel.jpgRigelRigelhttps://exastra.blog/wp-content/uploads/2017/04/spica.jpgSpicaSpicahttps://exastra.blog/wp-content/uploads/2017/04/bellatrix.jpegbellatrixBellatrixhttps://exastra.blog/wp-content/uploads/2017/04/antares1.jpgAntaresAntareshttps://exastra.blog/wp-content/uploads/2017/04/arcturus.gifArcturusArturohttps://exastra.blog/wp-content/uploads/2017/04/aldebaran1.pngAldebaranAldebaranhttps://exastra.blog/wp-content/uploads/2017/04/simulazione_binocolo_stellarium_m42.pngsimulazione_binocolo_stellarium_m42https://exastra.blog/wp-content/uploads/2017/04/stellarium_oculare_binocolo.pngstellarium_oculare_binocolohttps://exastra.blog/wp-content/uploads/2017/04/m45-50.pngM45-50M45, le Pleiadi, , per come appare ad un binocolo 10x50.https://exastra.blog/wp-content/uploads/2017/04/m44-50.pngM44-50M44, l'alveare, il presepe, , per come appare ad un binocolo 10x50.2017-04-30T12:42:51+00:00monthlyhttps://exastra.blog/2017/03/21/sinestesia/https://exastra.blog/wp-content/uploads/2017/03/m44_nfo.jpgm44_nfoM44, lunga esposizione, Greg Parker e Noel Carboni https://exastra.blog/wp-content/uploads/2017/03/ngc654.jpgProcessed with MaxIm DLNGC654, lunga esposizione.https://exastra.blog/wp-content/uploads/2017/03/m44-50.pngM44-50Dimensione di M44 nel campo visivo di un binocolo 10x50.https://exastra.blog/wp-content/uploads/2017/03/jewelbox_willasch_big.jpgjewelbox_willasch_bigM44, lunga esposizione, autore sconosciuto. Alcuni dei colori sono già percettibili attraverso il binocolo.https://exastra.blog/wp-content/uploads/2017/03/cancro_stellarium.jpgCancro_stellariumCostellazione del Cancro. Software Stellarium. M44 (Beehive cluster, gruppo alveare) è proprio lì, in mezzo.https://exastra.blog/wp-content/uploads/2017/03/piede_castore.jpgpiede_castoreDettaglio del piede di Castore. M35 è ben visibile appena sopra. Software Stellarium.https://exastra.blog/wp-content/uploads/2017/03/m35-dw.jpgM35-DWL'ammasso aperto M35, l'insieme di stelle azzurre sulla sinistra ed NGC 2158, un ulteriore ammasso aperto nelle vicinanze di quest'ultimo, più fitto e meno appariscente, in basso a destra. Foto di Dieter Willasch.https://exastra.blog/wp-content/uploads/2017/03/m35-50.pngM35-50M35 come appare nel campo visivo di un binocolo 10x50. A dire il vero, si vede molto meglio di come è qui rappresentato. Luminosità e stelle, almeno nel mio caso, erano sicuramente maggiori per intensità e numero.https://exastra.blog/wp-content/uploads/2017/03/gemelli_stellarium.jpgGemelli_stellariumI Gemelli. Castore è il fratello sulla destra. Il suo piede, il più lungo, è quello in cui cercare M35, poco più in alto. Software Stellarium.https://exastra.blog/wp-content/uploads/2017/03/messier-36.jpgMessier-36M36, lunga esposizione, http://cs.astronomy.com utente Wikisky 2017-04-14T09:05:38+00:00monthlyhttps://exastra.blog/2017/04/04/seconda-stella-a-destra/https://exastra.blog/wp-content/uploads/2017/04/star_hopping_m3_3_step_chioma_di_berenice_passo_3_b.pngStar_hopping_M3_3_step_Chioma_di_Berenice_Passo_3_Bhttps://exastra.blog/wp-content/uploads/2017/04/star_hopping_m3_3_step_chioma_di_berenice_passo_3.pngStar_hopping_M3_3_step_Chioma_di_Berenice_Passo_3https://exastra.blog/wp-content/uploads/2017/04/star_hopping_m3_3_step_chioma_di_berenice_passo_2.pngStar_hopping_M3_3_step_Chioma_di_Berenice_Passo_2https://exastra.blog/wp-content/uploads/2017/04/star_hopping_m3_3_step_chioma_di_berenice_passo_1.pngStar_hopping_M3_3_step_Chioma_di_Berenice_Passo_1https://exastra.blog/wp-content/uploads/2017/04/star_hopping_m3_3_step_chioma_di_berenice.pngStar_hopping_M3_3_step_Chioma_di_Berenicehttps://exastra.blog/wp-content/uploads/2017/04/star_hopping_m3_da_cani_da_caccia_e_chioma_di_berenice.pngStar_hopping_M3_da_Cani_da_Caccia_e_Chioma_di_Berenicehttps://exastra.blog/wp-content/uploads/2017/04/cani_da_caccia.pngCani_da_cacciahttps://exastra.blog/wp-content/uploads/2017/04/star_hopping_da_cassiopea_m103_ngc654_m52.pngStar_hopping_da_Cassiopea_M103_NGC654_M52https://exastra.blog/wp-content/uploads/2017/04/starhop_sirio_aldebaran_da_cintura_di_orione.pngStarhop_Sirio_Aldebaran_da_cintura_di_Orionehttps://exastra.blog/wp-content/uploads/2017/04/star_hopping_da_orione_per_leone_e_regolo.pngStar_hopping_da_Orione_per_Leone_e_Regolo2017-04-04T09:54:46+00:00monthlyhttps://exastra.blog/2017/03/15/e-quindi-uscimmo-a-riveder-le-stelle/2017-03-14T23:13:44+00:00monthlyhttps://exastra.blog/2017/03/03/dont-panic/https://exastra.blog/wp-content/uploads/2017/03/ugc-8335.jpgugc-8335UGC 8335, telescopio Hubblehttps://exastra.blog/wp-content/uploads/2017/03/quintetto-di-stephan.jpgquintetto-di-stephanQuintetto di Stephan, telescopio Hubblehttps://exastra.blog/wp-content/uploads/2017/03/ngc-6240.jpgngc-6240NGC5240, telescopio Hubblehttps://exastra.blog/wp-content/uploads/2017/03/ngc-17.jpgngc-17NGC 17, telescopio Hubblehttps://exastra.blog/wp-content/uploads/2017/03/galassie-rosa.jpggalassie-rosaGalassie Rosa, telescopio Hubblehttps://exastra.blog/wp-content/uploads/2017/03/galassie-collisione-ngc-6621-ngc-6622.jpggalassie-collisione-ngc-6621-ngc-6622NGC6621 e 6622, telescopio Hubblehttps://exastra.blog/wp-content/uploads/2017/03/galassie-antenne-collisione.jpggalassie-antenne-collisioneGalassie Antenna, telescopio Hubblehttps://exastra.blog/wp-content/uploads/2017/03/galassia-girino.jpggalassia-girinoGalassia Girino, telescopio Hubblehttps://exastra.blog/wp-content/uploads/2017/03/1-simon-marius1.jpg1-simon-mariusSimon Mariushttps://exastra.blog/wp-content/uploads/2017/03/meeting_the_neighbours.jpgMeeting the neighboursPGC 18431, telescopio Hubble2017-03-03T23:01:57+00:00monthlyhttps://exastra.blog/2017/01/24/fiat-lux/2017-02-12T14:36:35+00:00monthlyhttps://exastra.blog/2017/02/11/i-cannoni-di-navarone/https://exastra.blog/wp-content/uploads/2017/02/celestron-11-schmidt-cassegrain-cge-pro-telescope-2ea.jpgcelestron-11-schmidt-cassegrain-cge-pro-telescope-2eahttps://exastra.blog/wp-content/uploads/2017/02/casegraintelescope.pngcasegraintelescopehttps://exastra.blog/wp-content/uploads/2017/02/skbkp2001eq5.jpgskbkp2001eq5https://exastra.blog/wp-content/uploads/2017/02/newtontelescope1.pngnewtontelescopehttps://exastra.blog/wp-content/uploads/2017/02/newtontelescope.pngnewtontelescopehttps://exastra.blog/wp-content/uploads/2017/02/6f15c4893ffdc2f14c8dc42520c4c90e_9070000_m.jpg6f15c4893ffdc2f14c8dc42520c4c90e_9070000_mhttps://exastra.blog/wp-content/uploads/2017/02/diaframmi.jpgdiaframmihttps://exastra.blog/wp-content/uploads/2017/02/keplertelescope.pngkeplertelescopehttps://exastra.blog/wp-content/uploads/2017/02/le-35mmscale1w.jpgle-35mmscale1whttps://exastra.blog/wp-content/uploads/2017/02/kepler-supernova-remnant1.jpgkepler-supernova-remnantSupernova di Keplero, falsi colori, NASA2017-02-11T00:39:00+00:00monthlyhttps://exastra.blog/2017/02/07/h/https://exastra.blog/wp-content/uploads/2017/02/the_material_around_sn_1987a.jpgthe_material_around_sn_1987aI resti di SN 1987a (ESO / L. Calçada)https://exastra.blog/wp-content/uploads/2017/02/sig06-030.jpgsig06-030N49, resto di supernova diffuso visibile nella Grande Nube di Magellano. (Wikipedia)https://exastra.blog/wp-content/uploads/2017/02/nasa-snr0519690-chandraxrayobservatory-20150122.jpgFive objects at various distances that have been observed by ChandraUn resto di supernova nella Grande Nube di Magellano, immagine che combina riprese ai raggi-x e luce visibile. (Wikipedia)https://exastra.blog/wp-content/uploads/2017/02/crab_nebula.jpgcrab_nebulaNebulosa del Granchio (Wikipedia)https://exastra.blog/wp-content/uploads/2017/02/ring_nebula1.jpgring_nebulaImmagine della M57 ottenuta da Hubble Space Telescope. Credit: NASA/ESAhttps://exastra.blog/wp-content/uploads/2017/02/nebulosa-ngc-5189-copy.jpgnebulosa-ngc-5189-copyNGC 5189 fotografata da Hubble Space Telescope. Credit: NASA/ESA/Hubblehttps://exastra.blog/wp-content/uploads/2017/02/nebulosa-farfalla-copy.jpgnebulosa-farfalla-copyThis ceNebulosa Farfalla, o NGC 6302, fotografata qui da Hubble Space Telescope. Credit: NASA/ESA/Hubblelestial object looks like a delicate butterfly. But it is far from serene. What resemble dainty butterfly wings are actually roiling cauldrons of gas heated to nearly 20 000 degrees Celsius. The gas is tearing across space at more than 950 000 kilometres per hour — fast enough to travel from Earth to the Moon in 24 minutes! A dying star that was once about five times the mass of the Sun is at the centre of this fury. It has ejected its envelope of gases and is now unleashing a stream of ultraviolet radiation that is making the cast-off material glow. This object is an example of a planetary nebula, so-named because many of them have a round appearance resembling that of a planet when viewed through a small telescope. The Wide Field Camera 3 (WFC3), a new camera aboard the NASA/ESA Hubble Space Telescope, snapped this image of the planetary nebula, catalogued as NGC 6302, but more popularly called the Bug Nebula or the Butterfly Nebula. WFC3 was installed by NASA astronauts in May 2009, during the Servicing Mission to upgrade and repair the 19-year-old Hubble. NGC 6302 lies within our Milky Way galaxy, roughly 3800 light-years away in the constellation of Scorpius. The glowing gas is the star's outer layers, expelled over about 2200 years. The "butterfly" stretches for more than two light-years, which is about half the distance from the Sun to the nearest star, Proxima Centauri. The central star itself cannot be seen, because it is hidden within a doughnut-shaped ring of dust, which appears as a dark band pinching the nebula in the centre. The thick dust belt constricts the star's outflow, creating the classic "bipolar" or hourglass shape displayed by some planetary nebulae. The star's surface temperature is estimated to be over 220 000 degrees Celsius, making it one of the hottest known stars in our galaxy. Spectroscopic observations made with ground-based telescopes show that the gas is roughly 20 000 degrees Celsius, which is unusually hot compared to a typical planetary nebula. The WFC3 image reveals a complex history of ejections from the star. The star first evolved into a huge red giant, with a diameter of about 1000 times that of our Sun. It then lost its extended outer layers. Some of this gas was cast off from its equator at a relatively slow speed, perhaps as low as 32 000 kilometres per hour, creating the doughnut-shaped ring. Other gas was ejected perpendicular to the ring at higher speeds, producing the elongated "wings" of the butterfly-shaped structure. Later, as the central star heated up, a much faster stellar wind, a stream of charged particles travelling at more than 3.2 million kilometres per hour, ploughed through the existing wing-shaped structure, further modifying its shape. The image also shows numerous finger-like projections pointing back to the star, which may mark denser blobs in the outflow that have resisted the pressure from the stellar wind. The nebula's reddish outer edges are largely due to light emitted by nitrogen, which marks the coolest gas visible in the picture. WFC3 is equipped with a wide variety of filters that isolate light emitted by various chemical elements, allowing astronomers to infer properties of the nebular gas, such as its temperature, density and composition. The white-coloured regions are areas where light is emitted by sulphur. These are regions where fast-moving gas overtakes and collides with slow-moving gas that left the star at an earlier time, producing shock waves in the gas (the bright white edges on the sides facing the central star). The white blob with the crisp edge at upper right is an example of one of those shock waves. NGC 6302 was imaged on 27 July 2009 with Hubble's Wide Field Camera 3 in ultraviolet and visible light. Filters that isolate emissions from oxygen, helium, hydrogen, nitrogen and sulphur from the planetary nebula were used to create this composite image. These Hubble observations of the planetary nebula NGC 6302 are part of the Hubble Servicing Mission 4 Early Release Observations.https://exastra.blog/wp-content/uploads/2017/02/nebulosa-eschimese-copy.jpgnebulosa-eschimese-copyNebulosa dell'Eschimese fotografata da Hubble Space Telescope. Credit: NASA/ESA/Hubblehttps://exastra.blog/wp-content/uploads/2017/02/nebulosa-clessidra-copy.jpgnebulosa-clessidra-copyNebulosa Clessidra vista da Hubble Space Telescope. Credit: NASA/ESA/Hubblehttps://exastra.blog/wp-content/uploads/2017/02/eso1532a-copy.jpgThe planetary nebula ESO 378-1ESO 378-1: è stata catturata dal VLT (Very Large Telescope) dell’ESO nel nord del Cile. Crediti: ESO2017-02-10T09:18:54+00:00monthlyhttps://exastra.blog/2017/01/25/scripta-manent/https://exastra.blog/wp-content/uploads/2017/01/61wgyz6tgwl-_sx404_bo1204203200_.jpg61wgyz6tgwl-_sx404_bo1204203200_https://exastra.blog/wp-content/uploads/2017/01/610x2sdb2tl-_sx404_bo1204203200_.jpg610x2sdb2tl-_sx404_bo1204203200_https://exastra.blog/wp-content/uploads/2017/01/51nlnwve90l-_sx327_bo1204203200_.jpg51nlnwve90l-_sx327_bo1204203200_2017-02-05T22:16:22+00:00monthlyhttps://exastra.blog/2017/02/01/pellicola-2-0/https://exastra.blog/wp-content/uploads/2017/02/qsi_500_series_filter_wheel.jpgqsi_500_series_filter_wheelhttps://exastra.blog/wp-content/uploads/2017/02/moraviang4.jpgmoraviang4https://exastra.blog/wp-content/uploads/2017/02/point-and-shoot-camera.jpgpoint-and-shoot-camerahttps://exastra.blog/wp-content/uploads/2017/02/dslr_liveview.jpgdslr_liveviewhttps://exastra.blog/wp-content/uploads/2017/02/sviluppo.jpgsviluppohttps://exastra.blog/wp-content/uploads/2017/02/sviluppopellicola_04.jpgsviluppopellicola_04https://exastra.blog/wp-content/uploads/2017/02/additiva.gifadditivahttps://exastra.blog/wp-content/uploads/2017/02/iklhfnwstcwdv1uc-huge_.jpgiklhfnwstcwdv1uc-huge_https://exastra.blog/wp-content/uploads/2017/02/canon-sensore-da-250-megapixel.jpgcanon-sensore-da-250-megapixelhttps://exastra.blog/wp-content/uploads/2017/02/praktica_mtl3_924.jpgpraktica_mtl3_9242017-02-01T17:28:04+00:00monthlyhttps://exastra.blog/2017/01/26/the-dark-side-of-the-moon/https://exastra.blog/wp-content/uploads/2017/01/ha-hargb-comparison-astrophotography.jpgha-hargb-comparison-astrophotographyhttps://exastra.blog/wp-content/uploads/2017/01/strum121h.jpgstrum121hhttps://exastra.blog/wp-content/uploads/2017/01/pink-floyd-the-dark-side-of-the-moon-promo-back.jpgpink-floyd-the-dark-side-of-the-moon-promo-backhttps://exastra.blog/wp-content/uploads/2017/01/pink-floyd-dark-side-of-the-moon.jpgpink-floyd-dark-side-of-the-moonhttps://exastra.blog/wp-content/uploads/2017/01/bayerpattern.jpegbayerpatternhttps://exastra.blog/wp-content/uploads/2017/01/chipincamera.jpgchipincamerahttps://exastra.blog/wp-content/uploads/2017/01/2000px-em_spectrum_properties_it-svg.png2000px-em_spectrum_properties_it-svghttps://exastra.blog/wp-content/uploads/2017/01/rhjhhsm.jpgrhjhhsmhttps://exastra.blog/wp-content/uploads/2017/01/em_spectrum_properties_edit-svg.pngem_spectrum_properties_edit-svg2017-01-26T16:35:28+00:00monthlyhttps://exastra.blog/2017/01/25/mi-ritrovai-per-una-selva-oscura/https://exastra.blog/wp-content/uploads/2017/01/mainimage_orion_nebula_m42.jpgmainimage_orion_nebula_m42https://exastra.blog/wp-content/uploads/2017/01/img_9955_n.jpgimg_9955_n2017-01-25T12:50:44+00:00monthlyhttps://exastra.blog/chi-sono/2017-01-24T11:40:55+00:00weekly0.6https://exastra.blog/contatti/2017-01-24T11:38:47+00:00weekly0.6https://exastra.blogdaily1.02020-12-26T09:54:10+00:00