[phpBB Debug] PHP Warning: in file [ROOT]/phpbb/session.php on line 590: sizeof(): Parameter must be an array or an object that implements Countable
[phpBB Debug] PHP Warning: in file [ROOT]/phpbb/session.php on line 646: sizeof(): Parameter must be an array or an object that implements Countable
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 492: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 5133: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3843)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 5133: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3843)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 5133: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3843)
Εξωπλανήτης με γήινα χαρακτηριστικά - Σημαντική ανακάλυψη - sed.gr
[phpBB Debug] PHP Warning: in file [ROOT]/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1107: count(): Parameter must be an array or an object that implements Countable
ENGLEZOS
Site Admin
Δημοσιεύσεις: 1848
Εγγραφή: 26 Φεβ 2002, 03:00
[phpBB Debug] PHP Warning: in file [ROOT]/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1107: count(): Parameter must be an array or an object that implements Countable

30 Σεπ 2010, 17:04

Εξωπλανήτης με γήινα χαρακτηριστικά

Αμερικανοί αστρονόμοι ανακάλυψαν για πρώτη φορά έναν πλανήτη όπου είναι πολύ πιθανό να υπάρχει ζωή. Ο εξωπλανήτης, που πιθανώς διαθέτει βραχώδη επιφάνεια, ατμόσφαιρα και νερό, έχει το μέγεθος περίπου της γης, θα μπορούσε να είναι κατοικήσιμος λόγω της κατάλληλης θερμοκρασίας του και περιφέρεται γύρω από ένα κοντινό άστρο.

Οι επιστήμονες πιστεύουν ότι 20 έως 40 δισεκατομμύρια «γήινοι» εξωπλανήτες υπάρχουν μόνο στο γαλαξία μας και σιγά σιγά θα ανακαλύπτονται, καθώς εντείνεται η σχετική αστρονομική έρευνα.

Η ανακάλυψη, που παρουσιάζεται στο περιοδικό αστροφυσικής «Astrophysical Journal», έγινε μετά από 11 χρόνια παρατηρήσεων με τη βοήθεια του δέκα μέτρων τηλεσκοπίου Κεκ της Χαβάης από αστρονόμους του πανεπιστημίου της Καλιφόρνια Σάντα Κρουζ και του Ινστιτούτου Κάρνεγκι της Ουάσιγκτον, υπό τον καθηγητή αστρονομίας και αστροφυσικής Στίβεν Βογκτ.

Ο Gliese 581g περιστρέφεται σε σχεδόν κυκλική τροχιά κάθε 37 γήινες μέρες γύρω από ένα άστρο -νάνο μαζί με άλλους πέντε εξωπλανήτες. Βρίσκεται σε απόσταση «μόνο» 20 ετών φωτός από τη Γη στον αστερισμό του Ζυγού.

Ο πλανήτης φαίνεται να έχει τριπλάσια έως τετραπλάσια μάζα και διάμετρο μεγαλύτερη κατά 1,2 έως 1,4 φορές σε σχέση με τη Γη. Δεν είναι ούτε πολύ ζεστός, ούτε πολύ κρύος, πράγμα που τον τοποθετεί στην «ιδανική» ζώνη των κατοικήσιμων πλανητών, που θα μπορούσαν να φιλοξενούν κάποιες μορφές ζωής.

Όπως η Σελήνη, η μια πλευρά του εξωπλανήτη είναι «κλειδωμένη» και λούζεται μόνιμα στο φως του ήλιου, ενώ η άλλη βρίσκεται μόνιμα στο σκοτάδι.

Η πιο κατοικήσιμη περιοχή του πλανήτη θα είναι αυτή που αποτελεί το «σύνορο» ανάμεσα στις ζώνες του φωτός (με εκτιμώμενη θερμοκρασία 71 βαθμών Κελσίου) και του σκοταδιού (με θερμοκρασία μείον 34 βαθμών). Όμως, θα είναι δύσκολο οι επιστήμονες να μάθουν αν όντως ο συγκεκριμένος εξωπλανήτης φιλοξενεί ζωή, τουλάχιστον μέχρι να αναπτυχθούν νέες μέθοδοι και τεχνικές για την εξ αποστάσεως μελέτη ιχνών ζωής στην ατμόσφαιρα ενός τόσο μακρινού ουρανίου σώματος.

Μέχρι στιγμής έχουν βρεθεί περίπου 500 εξωπλανήτες, αλλά κανείς ως τώρα δεν φαινόταν να πληροί τις προϋποθέσεις για φιλοξενία ζωής.
Μπάμπης Εγγλέζος

[phpBB Debug] PHP Warning: in file [ROOT]/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1107: count(): Parameter must be an array or an object that implements Countable
[phpBB Debug] PHP Warning: in file [ROOT]/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1107: count(): Parameter must be an array or an object that implements Countable
[phpBB Debug] PHP Warning: in file [ROOT]/vendor/twig/twig/lib/Twig/Extension/Core.php on line 1107: count(): Parameter must be an array or an object that implements Countable

Επιστροφή στο

Μέλη σε σύνδεση

Μέλη σε αυτή την Δ. Συζήτηση: Δεν υπάρχουν εγγεγραμμένα μέλη και 2 επισκέπτες