Acrobase  

Καλώς ήρθατε στην AcroBase.
Δείτε εδώ τα πιο πρόσφατα μηνύματα από όλες τις περιοχές συζητήσεων, καθώς και όλες τις υπηρεσίες της AcroBase.
H εγγραφή σας είναι γρήγορη και εύκολη.

Επιστροφή   Acrobase > Ελεύθερος Χρόνος και Ψυχαγωγία > Καθημερινά ενημερωτικά θέματα
Ομάδες (Groups) Τοίχος Άρθρα acrobase.org Ημερολόγιο Φωτογραφίες Στατιστικά

Notices

Δεν έχετε δημιουργήσει όνομα χρήστη στην Acrobase.
Μπορείτε να το δημιουργήσετε εδώ

Απάντηση στο θέμα
 
Εργαλεία Θεμάτων Τρόποι εμφάνισης
  #811  
Παλιά 06-02-09, 09:33
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

Space Station in the Moon
Credit & Copyright: Eric J. Zbinden

Explanation: On February 2nd, a first quarter Moon shone in planet Earth's early evening sky. As seen from a location on the US west coast near Mt. Hamilton, California, the International Space Station also arched above the horizon, crossing in front of the Moon's sunlit surface. The space station's transit lasted 0.49 seconds. This sharp exposure, a well-timed telescopic image, recorded the space station during the transit against the background of the Moon's smooth Mare Serenitatis (Sea of Serenity). The orbital outpost was traveling northwest to southeast (from 2 o'clock to 8 o'clock) at a range of 389 kilometers or about 230 miles. Of course, the Moon itself was 1,000 times farther away. In the remarkable photo, the glinting station also offers a hint of the bluish reflection of earthlight.

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #812  
Παλιά 07-02-09, 08:53
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

Comet Lulin Tails
Credit & Copyright: Joseph Brimacombe

Explanation: Sweeping through the inner solar system, Comet Lulin is easily visible in both northern and southern hemispheres with binoculars or a small telescope. Recent changes in Lulin's lovely greenish coma and tails are featured in this two panel comparison of images taken on January 31st (top) and February 4th. Taken from dark New Mexico Skies, the images span over 2 degrees. In both views the comet sports an apparent antitail at the left -- the comet's dust tail appearing almost edge on from an earth-based perspective as it trails behind in Lulin's orbit. Extending to the right of the coma, away from the Sun, is the beautiful ion tail. Remarkably, as captured in the bottom panel, Comet Lulin's ion tail became disconnected on February 4, likely buffeted and torn away by magnetic fields in the solar wind. In 2007 NASA satellites recorded a similar disconnection event for Comet Encke. Don't worry, though. Comet tails can grow back.

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #813  
Παλιά 09-02-09, 08:18
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

Anemic Galaxy NGC 4921 at the Edge
Credit: NASA, ESA, K. Cook (LLNL)

Explanation: How far away is spiral galaxy NGC 4921? Although presently estimated to be about 320 million light years distant, a more precise determination could be coupled with its known recession speed to help humanity better calibrate the expansion rate of the entire visible universe. Toward this goal, this image was taken by the Hubble Space Telescope in order to help identify key stellar distance markers know as Cepheid variable stars. Since NGC 4921 is a member of the Coma Cluster of Galaxies, refining its distance would also allow a better distance determination to one of the largest NGC 4921 has been informally dubbed anemic because of its low rate of star formation and low surface brightness. The remarkably sharp image was made with Hubble's Advanced Camera for Surveys, currently in need of repair. Visible in the image are, from the center, a bright nucleus, a bright central bar, a prominent ring of dark dust, blue clusters of recently formed stars, several smaller companion galaxies, unrelated galaxies in the far distant universe, and unrelated stars in our Milky Way Galaxy.

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #814  
Παλιά 10-02-09, 09:18
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

Orion's Belt
Credit & Copyright: Martin Mutti, Astronomical Image Data Archive

Explanation: Alnitak, Alnilam, and Mintaka, are the bright bluish stars from east to west (left to right) along the diagonal in this gorgeous cosmic vista. Otherwise known as the Belt of Orion, these three blue supergiant stars are hotter and much more massive than the Sun. They lie about 1,500 light-years away, born of Orion's well-studied interstellar clouds. In fact, clouds of gas and dust adrift in this region have intriguing and some surprisingly familiar shapes, including the dark Horsehead Nebula and Flame Nebula near Alnitak at the lower left. The famous Orion Nebula itself lies off the bottom of this star field that covers about 4.5x3.5 degrees on the sky. This image was taken last month with a digital camera attached to a small telescope in Switzerland, and better matches human color perception than a more detailed composite taken over 15 years ago.

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #815  
Παλιά 11-02-09, 10:14
Το avatar του χρήστη pazo
pazo Ο χρήστης pazo δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: Σήμερα 10:23
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

Orion's Belt Continued
Credit & Copyright: Alan Smallbone

Explanation: Yesterday's skyscape featured Alnitak, Alnilam, and Mintaka, the stars of Orion's Belt. Today's also presents the easternmost belt star, Alnitak, at the bottom right of the field, surrounded by the well-known Horsehead and Flame nebulae. But this view sweeps farther to the east (left) and north (top) detailing subtler cosmic clouds of gas and dust scattered through the fertile, nebula rich region. The scene is anchored at the top left by the eerie blue glow and ominous dark dust lanes of reflection nebula M78. Like the Horsehead, the Flame, and the Orion Nebula itself, M78 is a readily visible part of the large Orion Molecular Cloud complex some 1,500 light-years distant.

Πηγή
__________________
VmF Skisters of Mercy ©
An eye for an eye, will make us all blind... Mahatma Ghandi
Απάντηση με παράθεση
  #816  
Παλιά 12-02-09, 09:43
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

Zodiacal Light Vs. Milky Way
Credit & Copyright: Daniel López, IAC

Explanation: Two fundamental planes of planet Earth's sky compete for attention in this remarkable wide-angle vista, recorded on January 23rd. Arcing above the horizon and into the night at the left is a beautiful band of Zodiacal Light - sunlight scattered by dust in the solar system's ecliptic plane. Its opponent on the right is composed of the faint stars, dust clouds, and nebulae along the plane of our Milky Way Galaxy. Both celestial bands stand above the domes and towers of the Teide Observatory on the island of Tenerife. Also out to play in the pristine, dark skies over the Canary Islands, are brilliant Venus (lower left), the distant Andromeda Galaxy (near center), and the lovely Pleiades star cluster (top center). Of course, seasoned skygazers might even spot M33, the California Nebula, IC1805, and the double star cluster of Perseus. (Need some help? Just slide your cursor over the picture.)

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #817  
Παλιά 14-02-09, 10:20
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

IC 1805: The Heart Nebula
Credit & Copyright: Daniel Marquardt

Explanation: Sprawling across almost 200 light-years, emission nebula IC 1805 is a mix of glowing interstellar gas and dark dust clouds. Derived from its Valentine's-Day-approved shape, its nickname is the Heart Nebula. About 7,500 light-years away in the Perseus spiral arm of our galaxy, stars were born in IC 1805. In fact, near the cosmic heart's center are the massive hot stars of a newborn star cluster also known as Melotte 15, about 1.5 million years young. A little ironically, the Heart Nebula is located in the constellation Cassiopeia. From Greek mythology, the northern constellation is named for a vain and boastful queen. This deep view of the region around the Heart Nebula, cropped from a larger mosaic, spans about 2.5 degrees on the sky or about 5 times the diameter of the Full Moon.

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #818  
Παλιά 15-02-09, 09:15
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας


Antarctic Ice Shelf Vista
Credit & Copyright: Helmut Rott (U. Innsbruck)

Explanation: It's all gone but the mountains. Most of the sprawling landscape of ice that lies between the mountains visible above has now disintegrated. The above picture was taken in Antarctica from the top of Grey Nunatak, one of three Seal Nunatak mountains that border the Larsen B Ice-Shelf. The other two nunataks are visible in the picture taken in 1994. Over the past several years large chunks of the 200-meter thick Larsen B Ice-Shelf have been breaking off and disintegrating. The cause is the local high temperatures of recent years, part of a planet wide climate change called global warming. Over the past few years, the area that has disintegrated is roughly the size of Luxembourg. As ice-shelves break up, they unblock other ice sheets that fall onto the ocean, raising sea levels everywhere. Scientists are watching the much-larger Ross Ice Shelf, which, if it fully collapses, could cause global sea levels to rise five meters over the next few hundred years.

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #819  
Παλιά 16-02-09, 09:03
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

The Great Carina Nebula
Credit: European Southern Observatory

Explanation: A jewel of the southern sky, the Great Carina Nebula, aka NGC 3372, spans over 300 light-years, one of our Galaxy's largest star forming regions. Like the smaller, more northerly Great Orion Nebula, the Carina Nebula is easily visible to the unaided eye, though at a distance of 7,500 light-years it is some 5 times farther away. This stunning telescopic view from the 2.2-meter ESO/MPG telescope La Silla Observatory in Chile reveals remarkable details of the region's glowing filaments of interstellar gas and dark cosmic dust clouds. The Carina Nebula is home to young, extremely massive stars, including the still enigmatic variable Eta Carinae, a star with well over 100 times the mass of the Sun. Eta Carinae is the bright star left of the central dark notch in this field and near the dusty Keyhole Nebula (NGC 3324).

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #820  
Παλιά 17-02-09, 09:33
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

Unusual Red Glow Over Minnesota
Credit & Copyright: Tyler Blessing

Explanation: What in heaven's blazes is that? When landing in Minneapolis, Minnesota, USA in 2002, just after his flight descended below cloud level in the early evening, passenger Tyler Blessing saw and photographed "huge curved sheets of glowing light extending from cloud to ground." The glow appeared unlike other unusual lights more typically seen, including crepuscular rays, anticrepuscular rays and the glory. A leading possibility, mentioned initially by the photographer, is that the light sheets are setting sunlight scattered off of falling rain. Alternatively, the phenomenon could just be a peculiar window reflection. APOD readers, who have previously shown an impressive ability to pool their collective intelligence to create a better understanding of photographed sky anomalies, are invited to discuss this online. It might help to know that EXIF data indicates that the image was captured on 2002 September 23 at about 8:07 pm in the evening (local time), and that the camera was reported to be pointing north of west at that time. The oval on the ground, visible in the lower right of the above image, is Canterbury Downs race track.

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #821  
Παλιά 18-02-09, 09:50
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

Satellites Collide in Low Earth Orbit
Illustration Credit & Copyright: Analytical Graphics, Inc.

Explanation: How often do satellites collide? Although minuscule space debris may strike any satellite on occasion, the first known collision between time two full satellites occurred only last week. Even though thousands of satellites have been launched, the low collision rate is caused by the great vastness of space. Last week, however, a defunct Russian communications satellite named Cosmos 2251 smashed right into an operational US communications satellite named Iridium 33 over Siberia, Russia. Both satellites were destroyed. The sheer number of massive particles in a dispersing debris cloud, depicted in an inset image above, increases the risk that other operating satellites might be struck by a harmful fast-moving projectile. The collision occurred in low Earth orbit only 750 kilometers up, a height shared by many satellites but significantly higher than the 350-km high human-occupied International Space Station. Since satellites may disintegrate when struck by fast-moving space junk, the crash focuses concern that a future dramatic satellite collision may one day start an ablation cascade of increasingly more collisions. The result could then render future human space flights increasingly risky and expensive satellite lifetimes increasingly short.

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #822  
Παλιά 19-02-09, 09:19
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας


Mauna Kea Milky Way Panorama
Credit & Copyright: Wally Pacholka (TWAN)

Explanation: Aloha and welcome to a breathtaking skyscape. The dreamlike panoramic view looks out from the 4,200 meter volcanic summit of Mauna Kea, Hawai'i, across a layer of clouds toward a starry night sky and the rising Milky Way. Anchoring the scene on the far left is the dome of the Canada-France-Hawaii Telescope (CFHT), with north star Polaris shining beyond the dome to the right. Farther right, headed by bright star Deneb, the Northern Cross asterism is embedded along the plane of the Milky Way as it peeks above the horizon. Both Northern Cross and brilliant white Vega hang over a foreground grouping of cinder cones. Near the center are the reddish nebulae, stars and dust clouds of the central Milky Way. Below, illumination from the city lights of Hilo creates an eerie, greenish glow in the clouds. Red supergiant star Antares shines above the Milky Way's central bulge while bright Alpha Centauri lies still farther right, along the dusty galactic plane. Finally, at the far right is the large Gemini North Observatory. The compact group of stars known as the Southern Cross is just left of the telescope dome. Need some help identifying the stars? Just slide your cursor over the picture, or download this smaller, labeled panorama.

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #823  
Παλιά 20-02-09, 09:39
Το avatar του χρήστη pazo
pazo Ο χρήστης pazo δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: Σήμερα 10:23
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

Snake in the Dark
Credit & Copyright: Stéphane Guisard (Los Cielos de Chile)

Explanation: Dark nebulae snake across a gorgeous expanse of stars in this telescopic view toward the pronounceable constellation Ophiuchus and the center of our Milky Way Galaxy. In fact, the twisting central shape seen here is well known as the Snake Nebula. It is also listed as Barnard 72 (B72), one of 182 dark markings of the sky cataloged in the early 20th century by astronomer E. E. Barnard. Unlike bright emission nebulae and star clusters, Barnard's nebulae are interstellar dark clouds of obscuring gas and dust. Their shapes are visible in cosmic silhouette because they lie in the foreground along the line of sight to rich star fields and glowing stellar nurseries near the plane of our Galaxy. Many of Barnard's dark nebulae are themselves likely sites of future star formation. Barnard 72 is about 650 light years away. With bluish star 44 Ophiuchi at bottom left, the intriguing star field spans nearly 2 degrees or almost 20 light-years at the estimated distance of the Snake Nebula.

Πηγή
__________________
VmF Skisters of Mercy ©
An eye for an eye, will make us all blind... Mahatma Ghandi
Απάντηση με παράθεση
  #824  
Παλιά 21-02-09, 09:47
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

The Swift View of Comet Lulin
Credit: NASA, Swift, Univ. Leicester, DSS (STScI/AURUA),
Dennis Bodewits (NASA/GSFC), et al.

Explanation: Now growing brighter, Comet Lulin is headed for its closest approach to planet Earth early next week. But the comet's greenish glow, familiar to earthbound skygazers, is replaced by false colors in this premier view from the orbiting Swift satellite. Image data from the Swift detectors, normally intended to follow cosmic gamma-ray bursts, were recorded on January 28. The data are combined here, along with a sky survey image of background stars, to show optical and ultraviolet light in green-blue hues and x-rays from the comet in red. The result maps remarkable x-ray emission on the comet's sunward side as incoming solar wind ions interact with gases in the swollen coma. It also shows substantial ultraviolet emission opposite the Sun, in the direction of motion and the comet's tail. The ultraviolet emission is from the OH molecule derived from the breakup of water, an indicator of the copius amounts of water produced by this extremely active comet. In fact, astronomers estimate Lulin was releasing about 800 gallons of water each second, enough to fill an Olympic-size swimming pool in less than 15 minutes.

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
  #825  
Παλιά 22-02-09, 09:36
Το avatar του χρήστη Xenios
Xenios Ο χρήστης Xenios δεν είναι συνδεδεμένος
Administrator
 

Τελευταία φορά Online: 12-11-16 11:12
Φύλο: Άντρας

Κάντε κλικ στην φωτογραφία για μεγάλη ανάλυση

Orion Nebula: The Hubble View
Credit: NASA, ESA, M. Robberto (STScI/ESA) et al.

Explanation: Few cosmic vistas excite the imagination like the Orion Nebula. Also known as M42, the nebula's glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud only 1,500 light-years away. The Orion Nebula offers one of the best opportunities to study how stars are born partly because it is the nearest large star-forming region, but also because the nebula's energetic stars have blown away obscuring gas and dust clouds that would otherwise block our view - providing an intimate look at a range of ongoing stages of starbirth and evolution. This detailed image of the Orion Nebula is the sharpest ever, constructed using data from the Hubble Space Telescope's Advanced Camera for Surveys and the European Southern Observatory's La Silla 2.2 meter telescope. The mosaic contains a billion pixels at full resolution and reveals about 3,000 stars.

Πηγή
__________________
όταν γράφεται η ιστορία της ζωής σου,
μην αφήνεις κανέναν να κρατάει την πένα
Απάντηση με παράθεση
Απάντηση στο θέμα


Συνδεδεμένοι χρήστες που διαβάζουν αυτό το θέμα: 6 (0 μέλη και 6 επισκέπτες)
 
Εργαλεία Θεμάτων
Τρόποι εμφάνισης

Δικαιώματα - Επιλογές
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is σε λειτουργία
Τα Smilies είναι σε λειτουργία
Ο κώδικας [IMG] είναι σε λειτουργία
Ο κώδικας HTML είναι σε λειτουργία

Που θέλετε να σας πάμε;


Όλες οι ώρες είναι GMT +3. Η ώρα τώρα είναι 19:29.



Forum engine powered by : vBulletin Version 3.8.2
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.