ΜΗΧΑΝΙΣΜΟΣ ΤΩΝ ΑΝΤΙΚΥΘΗΡΩΝ: Η επανεκκίνηση ενός αρχαίου υπολογιστή

Στις 30 Νοεμβρίου 2006, ξεκίνησε στην Αθήνα μια διημερίδα κατά την οποία ανακοινώθηκαν τα αποτελέσματα της πρόσφατης διερεύνησης του Μηχανισμού των Αντικυθήρων, από μια πολυμελή και πολυδιάστατη θεματικά ομάδα ερευνητών. Την ίδια ημέρα δημοσιευόταν ένα ιστορικό άρθρο στο διεθνές περιοδικό Nature, με το οποίο καθιερώθηκε πλέον ο τρόπος λειτουργίας του Μηχανισμού. Η νέα διερεύνηση χρησιμοποίησε καινοτόμες τεχνικές με τις οποίες εντοπίσθηκαν άγνωστες μέχρι τώρα λεπτομέρειες της λειτουργία του Μηχανισμού και διαβάστηκαν, για πρώτη φορά μετά από 2000 χρόνια, μεγάλα τμήματα από το εγχειρίδιο χρήσεως που τον συνόδευε.
Με την αποκωδικοποίηση του Μηχανισμού των Αντικυθήρων αναθεωρείται και ξαναγράφεται η ιστορία της Τεχνολογίας. Η μελέτη του μοναδικού αυτού ευρήματος, που χρονολογείται πριν από δύο χιλιετίες, επιβεβαίωσε, όχι μόνο τις λιγοστές μέχρι τώρα γραπτές μαρτυρίες για τις άριστες γνώσεις των αρχαίων Ελλήνων στις δαιδαλώδεις κινήσεις των ουράνιων σωμάτων, αλλά και την ικανότητά τους να εφαρμόζουν τις γνώσεις αυτές σε τεχνολογικές συσκευές, που ακόμα και σήμερα θα δυσκολευόμαστε να κατασκευάσουμε. Η μελέτη των θραυσμάτων, που ανασύρθηκαν από το βυθό της θάλασσας πριν από 100 περίπου χρόνια, έχει δώσει μια νέα διάσταση στο ζήτημα της εξέλιξης της Τεχνολογίας δια μέσου των αιώνων. Για την κατασκευή του πρέπει να συνεργάστηκαν δύο μεγαλοφυΐες: ένας άριστος γνώστης και ερευνητής της επιστήμης της Αστρονομίας και ένας ταλαντούχος τεχνίτης με πολύ καλές γνώσεις Μαθηματικών.

Ας δούμε όμως πως εξελίχθηκε η ιστορία της ανακάλυψης και η μελέτη του Μηχανισμού:

Τη Μεγάλη Τρίτη του έτους 1900, δηλαδή στις 4 Απριλίου, σύμφωνα με το Ιουλιανό ημερολόγιο που ίσχυε στη χώρα μας μέχρι το 1923, Σύμιοι σφουγγαράδες, προερχόμενοι από την Αφρική, αναγκάστηκαν να αγκυροβολήσουν στα Αντικύθηρα λόγω σφοδρής θαλασσοταραχής. Εκεί, ορμώμενοι είτε από επαγγελματική περιέργεια είτε για να μαζέψουν νηστίσιμα θαλασσινά, βούτηξαν και σε βάθος 40-50 μέτρων, ανακάλυψαν έναν από τους πιο διάσημους θησαυρούς της αρχαιότητας. Προς μεγάλη τους έκπληξη βρέθηκαν μπροστά σε ένα αρχαίο ναυάγιο, διάσπαρτο στο βυθό της θάλασσας σε μήκος τουλάχιστον 55 μέτρων (δηλαδή επρόκειτο για ένα τεράστιο καράβι), με πλούσιο περιεχόμενο. Λίγους μήνες αργότερα, το Νοέμβριο του 1900, η Εφορεία Αρχαιοτήτων ξεκίνησε μια σειρά συστηματικών ενάλιων ανασκαφών, η οποία διήρκεσε μέχρι το Σεπτέμβριο του 1901. Κατά τη διάρκεια των ανασκαφών ανασύρθηκαν σημαντικά ευρήματα πολλά από τα οποία εκτίθενται σήμερα στο Εθνικό Αρχαιολογικό Μουσείο των Αθηνών, όπως ο Έφηβος των Αντικυθήρων, ο περίφημος Φιλόσοφος των Αντικυθήρων, κ.α.. Ανασύρθηκαν και πολλά άλλα αγάλματα, ορειχάλκινα ή μαρμάρινα, σκεύη διατροφής και διασκέδασης (π.χ. μια μικρή λύρα), αμφορείς, ξύλινα τμήματα του πλοίου, κ.α. Ανάμεσα στα ευρήματα ήταν και ο Μηχανισμός των Αντικυθήρων. Πιθανώς, όταν ανασύρθηκε έμοιαζε με ένα απολιθωμένο όγκο με δείγματα ορείχαλκου, στον οποίο υπήρχαν εμφανώς γρανάζια και γράμματα.

Κατά τη δεκαετία του '70, ο περιηγητής Jacques Cousteau συνέβαλε στην ανασκαφή με το σκάφος του «Καλυψώ» και ομάδα εκπαιδευμένων δυτών, μεταξύ των οποίων και ο (φοιτητής τότε) Λευτέρης Τσαβλίρης. Ιδιαίτερα χρήσιμη για τη χρονολόγηση του ναυαγίου ήταν η εύρεση νομισμάτων από την Πέργαμο, κοπής μεταξύ 86-67 π.Χ., μερικών αγαλματιδίων και η ανέλκυση ενός μεγάλου ξύλινου τμήματος του καραβιού..
Ο Μηχανισμός είναι ένα εξαιρετικά πολύπλοκο αστρονομικό όργανο με τουλάχιστον 30 συνεργαζόμενα γρανάζια, η πολυπλοκότητα του οποίου είναι πολύ μεγαλύτερη από αυτήν όλων των συσκευών που κατασκευάστηκαν κατά την επόμενη χιλιετία. Κατασκευάστηκε κατά το δεύτερο ήμισυ του 2^ου π.Χ. αιώνα, πιθανότατα στη Ρόδο, όπου την εποχή αυτή, άνθιζε η επιστήμη της Αστρονομίας. Στη Ρόδο πέθανε το 120 π.Χ. ο μεγαλύτερος αστρονόμος της αρχαιότητας, ο Ίππαρχος. Εκεί έζησε, επίσης, ο γνωστότατος Στωικός φιλόσοφος και αστρονόμος,Ποσειδώνιος ο Ρόδιος.

EIKONA 1. Το κύριο θραύσμα A του Μηχανισμού των Αντικυθήρων, μεγίστης διαμέτρου περίπου 15 cm. Στο θραύσμα αυτό εντοπίσθηκαν τα 27 από τα 30 γνωστά γρανάζια του Μηχανισμού (Φωτό: K. Ξενικάκης).

Ο Derek de Solla Price ήταν ο πρώτος μελετητής του Μηχανισμού. Με τη συνεργασία του Χαράλαμπου Καράκαλου από το Ερευνητικό Κέντρο «Δημοκριτος» ο Price μελέτησε διεξοδικά το Μηχανισμό των Αντικυθήρων και το 1974 δημοσίευσε ένα εκτενές άρθρο στο περιοδικό Scientific American με τίτλο «Γρανάζια από τους Έλληνες». Στο άρθρο αυτό ισχυριζόταν ότι ο Μηχανισμός είναι ένα πολύπλοκο αστρονομικό όργανο, το οποίο μάλιστα περιείχε μια διάταξη γραναζιών, όπως αυτή που υπάρχει στα διαφορικά γρανάζια που χρησιμοποιούμε σήμερα στα αυτοκίνητά. Ο de Solla Price εργάστηκε πάνω από 30 χρόνια, μελετώντας το Μηχανισμό και στο άρθρο του αναφέρει επιγραμματικά ότι "είναι το παλαιότερο δείγμα επιστημονικής τεχνολογίας που διασώζεται μέχρι σήμερα και αλλάζει τελείως τις απόψεις μας για την αρχαία ελληνική τεχνολογία".
Τη σκυτάλη από τον Price πήραν στις αρχές του 1980 οι Alan Bromley και Michael Wright. Ο δεύτερος μάλιστα εξακολουθεί να μελετά εντατικά τo Μηχανισμό μέχρι σήμερα. Η ομάδα αυτή, μετά από πολυετή μελέτη, απέρριψε την ύπαρξη του διαφορικού γραναζιού και εισήγαγε μερικές καινοτόμες ιδέες για τη χρήση του Μηχανισμού. Για παράδειγμα, πρότεινε ότι οι κλίμακες στην όπισθεν πλευρά του Μηχανισμού, περιλαμβάνει μία σπειροειδή έλικα και όχι ομόκεντρους κύκλους. Τη σημασία αυτής της διαφοράς θα την αναλύσουμε παρακάτω.
Στις αρχές του 2001 μια ομάδα Ελλήνων και ξένων ερευνητών, στην οποία συμμετείχαν επιστήμονες από το Πανεπιστήμιου του Cardiff της Μ. Βρετανίας (Mike Edmunds, Antony Freeth), το Πανεπιστήμιο Αθηνών (Ξενοφών Μουσάς, Ιωάννης Μπιτσάκης) και το Πανεπιστήμιο Θεσσαλονίκης (Ιωάννης Σειραδάκης) δημιούργησαν την «Ομάδα Διερεύνησης του Μηχανισμού των Αντικυθήρων». Μετά από αλλεπάλληλες, άκαρπες αιτήσεις προς το Εθνικό Αρχαιολογικό Μουσείο (Μάρτιος 2001 - Αύγουστος 2004) η άδεια, τελικά, υπεγράφη από τον τότε Υπουργό Πολιτισμού Πέτρο Τατούλη, τον Απρίλιο 2005, μετά από προσωπική παρέμβασή του. Το έργο ετέθη υπό την αιγίδα του Υπουργείου Πολιτισμού και με την ευγενική χορηγία του Ιδρύματος Leverhulme της Μ. Βρετανίας πραγματοποιήθηκε μια νέα μελέτη του Μηχανισμού χρησιμοποιώντας σύγχρονα μέσα τεχνολογίας (π.χ. τομογραφία ακτίνων Χ με διακριτική ικανότητα 0.04 mm, οπτική φωτογράφηση με περιφερειακό φωτισμό, κ.α). Με την έναρξη των μετρήσεων, στην ομάδα συμμετείχαν η Ελένη Μάγκου και η Μαρία Ζαφειροπούλου από το Εθνικό Αρχαιολογικό Μουσείο των Αθηνών και αργότερα ο Αγαμέμνων Τσελίκας από το Μορφωτικό Ίδρυμα της Εθνικής Τραπέζης. Όπως αναφέρθηκε ήδη, στις 30 Νοεμβρίου (14 μήνες μετά την έναρξη της λήψη των μετρήσεων) η ερευνητική ομάδα ανακοίνωσε τα αποτελέσματα της μελέτης στο διεθνές περιοδικό "Nature" και συγχρόνως σε μια διημερίδα που έλαβε χώρα στην Αθήνα, σε συνεργασία με το Μορφωτικό Ίδρυμα της Εθνικής Τραπέζης.

EIKONA 2. Το θραύσμα 19 με την τεχνική PTM της Hewlett Packard. Διακρίνεται καθαρά τμήμα του εγχειριδίου χρήσεως του Μηχανισμού.

Τα αποτελέσματα της έρευνας, είναι εκπληκτικά: βρέθηκαν άγνωστες επιγραφές στο εσωτερικό του Μηχανισμού και διαβάστηκαν κείμενα χαμένα για πάνω από 2000 χρόνια! Η υψηλή διακριτική ικανότητα των μετρήσεων και η προσεκτική μελέτη των επιγραφών και των γραναζιών, επέτρεψε στην ερευνητική ομάδα να παρουσιάσει μια συνολική, κατά το δυνατόν, λύση στο μυστήριο της λειτουργίας του Μηχανισμού. Τα μέχρις στιγμής συμπεράσματα επιβεβαιώνουν ότι ο Μηχανισμός των Αντικυθήρων είναι ένα φορητό αστρονομικό όργανο, τόσο περίπλοκο που δεν είναι περίεργο πως θεωρείται ότι είναι ο πρώτος σύνθετος (αναλογικός) υπολογιστής που κατασκευάστηκε ποτέ. Ήταν δηλαδή ένα Laptop της εποχής του!
Ο Μηχανισμος των Αντικυθήρων εμπεριείχετο πιθανώς σε ένα ξύλινο κουτί (πυξίδα) διαστάσεων 30x20x10 εκ. και προστατευόταν με δύο ορειχάλκινες (μπρούτζινες) πλάκες (πορτούλες). Ο ορείχαλκος ήταν αρκετά μαλακός (περιείχε 4-10 % κασσίτερο). Στην μπροστινή πλευρά υπάρχουν δύο ομόκεντροι κύκλοι (εξωτερικός και εσωτερικός). Στην πίσω πλευρά υπάρχουν δύο σπειροειδείς έλικες (η πάνω, με 5 σπείρες, το συνολικό μήκος των οποίων διαιρείται σε 235 τμήματα και η κάτω, με 4 σπείρες, το συνολικό μήκος των οποίων διαιρείται σε 223 τμήματα). Δίπλα σε κάθε σπειροειδή έλικα υπάρχουν δύο μικροί κύκλοι με 4 υποδιαιρέσεις στον πάνω και 3 υποδιαιρέσεις στον κάτω.

EIKONA 3. Τμήμα της κάτω κλίμακας της πίσω όψης του Μηχανισμού των Αντικυθήρων μετά τη συναρμολόγηση των θραυσμάτων A, B, E και F. Η κλίμακα έχει 223 υποδιαιρέσεις (Περίοδος Σάρος των 223 μηνών). Σε πολλές από αυτές υπάρχουν σύμβολα, που υποδεικνύουν την πιθανότητα να συμβεί έκλειψη αυτόν το μηνα.

Ο χειριστής του Μηχανισμού, μπορούσε να επιλέξει, με τη βοήθεια ενός δείκτη μια οποιαδήποτε ημέρα από τις 365 που περιείχε ο εξωτερικός ετήσιος κύκλος της μπροστινής πλευράς του Μηχανισμού. Ο δείκτης αυτός έφερε πιθανώς στη μύτη του ένα «χρυσούν σφαιρίον», που περιγράφεται στις επιγραφές με οδηγίες χρήσεως, που πλουσιοπάροχα έφερε ο Μηχανισμός. Η επιλογή της ημέρας γινόταν με τη βοήθεια ενός μικρού περιστρεφόμενου στροφείου (μανιβέλας). Κάθε ημέρα, βέβαια, ο Ήλιος βρίσκεται σε μια ορισμένη θέση στον κύκλο των 12 ζωδιακών αστερισμών, που αναγράφονταν σε ένα εσωτερικό ομόκεντρο (προς τον ετήσιο) ζωδιακό κύκλο. Τα δίσεκτα έτη λαμβάνονταν υπόψη, μετατοπίζοντας τη θέση του ετήσιου κύκλου ως προς το ζωδιακό κατά μία ημέρα κάθε 4 έτη.
Κατά την επιλογή της ημερομηνίας με το στροφείο, τουλάχιστον πέντε άλλοι δείκτες κινούνταν και έδειχναν:

• Στη μπροστινή πλευρά: τη θέση της Σελήνης ανάμεσα στους ζωδιακούς αστερισμούς (και τη φάση αυτής με τη βοήθεια ενός (αργυρού) «ελάσσονος σφαιρίου»).
• Στην πάνω σπειροειδή έλικα της πίσω πλευράς: τη μηνιαία θέση της Σελήνης στην περίοδο του Μέτωνος (235 μήνες της Σελήνης, που με αρκετά καλή προσέγγιση διαρκούν 19 έτη μείον ένα τέταρτο της ημέρας) και στον αντίστοιχο μικρό κύκλο τη θέση της στην περίοδο του Καλλίπου (που είναι ίση με 75 έτη, δηλαδή 4 x 19 = 76 έτη μείον μία ημέρα). Μετά από μία πλήρη περίοδο του Μέτωνος η Σελήνη παρουσιάζει την ίδια φάση την ίδια ημέρα του έτους. Η περίοδος του Καλλίπου είναι μια καλύτερη προσέγγιση της περιόδου του Μέτωνος.
• Στην κάτω σπειροειδή έλικα της πίσω πλευράς ο δείκτης έδειχνε την περίοδο Saros, η οποία διαρκεί 223 μήνες (18 έτη και 11 ημέρες). Με την περίοδο Saros μπορούσε ο χειριστής να βρει την πιθανότητα να συμβούν ηλιακές ή σεληνιακές εκλείψεις. Για να έχουμε έκλειψη (Ηλίου ή Σελήνης) πρέπει ο Ήλιος, η Σελήνη και η Γη να βρίσκονται περίπου σε ευθεία γραμμή. Αυτό συμβαίνει τουλάχιστον δύο φορές το χρόνο. Επειδή η διεύθυνση της ευθείας αυτής περιστρέφεται στον ουρανό και κάνει μια πλήρη περιστροφή σε 223 μήνες (περίοδος Saros), εξυπακούεται ότι η διαδοχή των εκλείψεων επαναλαμβάνεται κάθε 223 μήνες. Επομένως, γνωρίζοντας ο χειριστής εκλείψεις του παρελθόντος, ήταν σε θέση να προβλέψει μελλοντικές εκλείψεις. Πράγματι, σε μερικά από τα 223 τμήματα (που αντιστοιχούσαν σε μήνες που έγιναν εκλείψεις) υπάρχουν συμβολικές επιγραφές, που αναφέρουν την ημέρα και την ώρα εκλείψεων!

Είναι προφανές ότι ο Μηχανισμός των Αντικυθήρων ήταν ένα πολύπλοκο όργανο. Έτσι δεν είναι περίεργο ότι συνοδευόταν και από ένα εκτεταμένο και αναλυτικό εγχειρίδιο χρήσεως (user's manual). Οι προστατευτικές πλάκες που αναφέρθηκαν παραπάνω ήταν γεμάτες με επιγραφές. Μέχρι τώρα έχουν διαβαστεί περίπου 1200 εγχάρακτα γράμματα, όλα της ελληνικής αλφαβήτου, τα οποία βεβαίως, σχηματίζουν λέξεις και προτάσεις, που αναφέρονται σε αστρονομικούς, γεωγραφικούς και τεχνικούς όρους. Το ύψος των περισσοτέρων γραμμάτων είναι, κατά μέσο όρο, 2.17 χιλιοστά. Φαίνεται ότι ήταν σμιλευμένα με πολύ λεπτά εργαλεία.
Σημαντική είναι η ανακάλυψη της λέξης «ΙΣΠΑΝΙΑ», ανάμεσα στις επιγραφές, που πιθανώς αποτελεί την πρώτη γραπτή χρήση της λέξεως. Οι αρχαίοι Έλληνες χρησιμοποιούσαν τη λέξη «ΕΣΠΕΡΙΑ» (επειδή βρίσκεται δυτικά της χώρας μας, προς τη διεύθυνση που δύει ο Ήλιος την εσπέρα), ή «ΗΒΗΡΙΑ». Η λέξη «ΙΣΠΑΝΙΑ» είναι, βέβαια, αρχαιότατη, αλλά χρησιμοποιήθηκε επισήμως, για πρώτη φορά από τους Ρωμαίους.
Επίσης εντοπίσθηκε η λέξη «ΦΑΡΟΣ» (προφανώς της Αλεξάνδρειας). Με άλλα λόγια στο εγχειρίδιο χρήσεως γίνονται αναφορές για ένα μεγάλο εύρος πόλεων της Μεσογείου. Στις πόλεις αυτές ίσως χρησιμοποιείτο ο Μηχανισμός.

Ο Μηχανισμός των Αντικυθήρων, ιδιαίτερα μετά το διημερίδα των Αθηνών, έχει κινήσει το παγκόσμιο ενδιαφέρον τόσο του επιστημονικού κόσμου όσο και του κοινού. Γι' αυτό η Ομάδα Διερεύνησης του Μηχανισμού των Αντικυθήρων έχει δημιουργήσει την ιστοσελίδα:http://www.antikythera-mechanism.gr για την πληροφόρηση του κοινού και των ειδικών. Είναι προφανές, από τη σύντομη αυτή περιγραφή, ότι ο Μηχανισμός των Αντικυθήρων αποτελεί ένα σημαντικότατο τεκμήριο για τις ικανότητες των αρχαίων Ελλήνων. Πιστεύουμε ότι η συμβολή του στην εξέλιξη της Τεχνολογίας είναι τόσο σημαντική όσο και η Ακρόπολις για την εξέλιξη της Αρχιτεκτονικής. Ελπίζουμε ότι σύντομα, λαμβάνοντας υπόψη τις γνώσεις που αποκτήσαμε για το θαυμάσιο όσο και αινιγματικό αυτό αντικείμενο με τη νέα μελέτη, θα μπορέσουμε να εκδώσουμε σχετικά φυλλάδια και βιβλία για το Μηχανισμό, να διανείμουμε σε όλα τα σχολεία της χώρας μας ένα DVD με κείμενα εικόνες και βίντεο και να κατασκευάσουμε ένα ακριβέστερο τριδιάστατο αντίγραφο του πρωτοτύπου, προβάλλοντας με τον καλύτερο τρόπο τόσο την επιστημονική όσο και την τεχνολογική κατάρτιση των αρχαίων Ελλήνων.

(photos and video)Parts of Germany have been hit by violent storms resulting in severe flooding and mudslides.

Parts of Germany have been hit by violent storms resulting in severe flooding and mudslides. At least four people are feared dead from the torrential overnight rains. Over 7,000 firefighters and other emergency response teams have been activated to deal with the aftermath.

At least three people have lost their lives as extreme weather, including flash floods, hail storms and lightning storms wreaked havoc in southern Germany on Sunday evening. The states of Baden-Württemberg and Bavaria were struggling to cope with the results of destructive storms on Monday morning. In Schwäbisch Gmünd in Baden-Württemberg a firefighter died on Sunday while trying to dig a stranded person out of trouble. The person he was trying to save is also likely dead, authorities said on Sunday evening. In Heilbronn, meanwhile, police also confirmed that one person died after being trapped in an underground garage during flooding. "We are using all the resources we have," a police spokesperson in the town said of the flooding. "It's not looking good here, it's looking really bad." Videos uploaded to the internet show torrential rain and powerful flash floods dragging everything that wasn't fixed to the ground with them. he number of casualties has not yet been confirmed by the state interior ministry in Baden-Württemberg. Police in the wealthy south-western state took thousands of emergency calls. In Ulm alone authorities recorded 490 emergency calls in a five-hour period. In Biberach a landslide dragged trees and mud onto an industrial area. The Autobahn between Giengen und Oberkochen had to been shut down after hail stones covered it to ankle height, with snow ploughs brought in to clear the asphalt. In the town of Künzelsau the major talked of a "natural disaster" after several roads had to be closed down while debris was cleared away. Particularly badly affected was the town of Braunsbach in the north of Baden-Württemberg. Local police spoke of wide-scale destruction after a river burst its banks. Video footage from the town shows the terrifying strength of the flooding as it surged through the streets. Much of the area had to be evacuated but there were no deaths reported. In Bavaria storms also caused massive damage. In Ansbach whole streets were flooded and powerful water flows ripped cars along with them. Some houses north of the town were so badly damaged that they could now collapse. Emergency services are now working to prop up the structures.

Floods have lashed southern Germany, killing at least four people and causing an underground carpark to collapse. The town of Schwäbisch Gmünd was the worst hit, with a volunteer firefighter drowning while trying to rescue a flood victim, Deutsche Welle reports. Two people died after a carpark filled with water and caved in. Scores of cars were submerged, while the strength of the water washed others down flooded streets. Hundreds of people have been evacuated across the state of Baden-Wuerttemberg, which borders France and Switzerland. The flood waters reportedly rose four metres within just minutes. It is not yet known how much rain has fallen across Baden-Wuerttemberg. Wild weather has lashed parts of Germany over the weekend, with more than 30 people taken to hospital in the western village of Hoppstaedten when lightning struck the pitch at the end of a children's football match. Three adults were seriously injured including the 45-year-old referee who was hit directly and had to be resuscitated before being rushed to hospital by helicopter, AFP reports.

ΕΠΙΣΚΕΨΗ ΠΟΥΤΙΝ ΣΤΟ ΑΓΙΟΝ ΟΡΟΣ-PHOTOS VIDEO

Chile's salt flat

The Sentinel-2A satellite takes us to the diverse landscape of the eastern Atacama desert in South America. The region pictured lies around 200km east of the Chilean city of Antofagasta on the Pacific coast (not pictured), and is virtually devoid of vegetation.
 At the top of the image we can see part of Chile’s largest salt flat, the Salar de Atacama. With an average elevation of some 2300 m above sea level, it is formed by waters flowing down from the Andes, which, having no drainage outlets, are forced to evaporate, leaving salt deposits.
 It is the world’s largest and purest active source of lithium, containing some 30% of the world's lithium reserve base, and providing almost 30% of the world’s lithium carbonate supply.
 The bright turquoise rectangles and squares visible along the top part of the image are evaporation ponds. Subsurface salt brines are pumped from beneath the saline crust in two different areas. In one of them, extracted salt brines have unrivalled concentration levels of potassium and lithium. In the other, the brines obtained contain high concentrations of sulphate and boron.
 In the lower right part of the image we can see the Socompa stratovolcano, known for its ‘debris avalanche deposit’ where the land collapsed on its western rim some 7000 years ago. The area has since been partially filled by lava, and we can see dark lava flows around the volcano.
 The multispectral instrument on Sentinel-2 uses parts of the infrared spectrum to analyse mineral composition where vegetation is sporadic. In this false-colour image, the intense shades of brown and orange come from the use of an infrared part of the spectrum leading to an exaggeration of colour intensity.
 This image – also featured on the Earth from Space video programme – was captured by Sentinel-2A on 8 March. The satellite is the first in the twin satellite Sentinel-2 mission for Europe’s Copernicus programme, and carries a wide-swath high-resolution multispectral imager with 13 spectral bands, for a new angle on our land and vegetation.

Συνέντευξη τύπου: Βλαντιμίρ Πούτιν - Αλέξης Τσίπρας (ΜΕΓΑΡΟ ΜΑΞΙΜΟΥ) 27.5.2016

President Barack Obama delivers remarks at the National Convention Center in Hanoi, Vietnam, May 24, 2016. PHOTO

President Barack Obama delivers remarks at the National Convention Center in Hanoi, Vietnam, May 24, 2016.

President Barack Obama takes a tour of the Jade Pagoda in Ho Chi Minh City, Vietnam, May 24, 2016. Duong Ngoc Dung, Professor of Philosophy, Ho Chi Minh City University of Social Sciences and Humanities and the head Abbot accompany him

People wave from along the street as President Barack Obama passed by in a motorcade after arriving in Ho Chi Minh City, Vietnam, May 24, 2016.

President Barack Obama talks with performers at the conclusion of a State Luncheon at the International Convention Center in Hanoi, Vietnam, May 23, 2016.

Guantanamo Bay: The remaining detainees

BY THOMAS JOSCELYN | May 24, 2016 | tjoscelyn@gmail.com | @thomasjoscelyn

Editor’s note: Below is Thomas Joscelyn’s testimony to the House Committee on Oversight and Government Reform, Subcommittee on National Security, on the remaining detainees held at Guantanamo Bay. For the PDF with footnotes, click here.

Chairman DeSantis, Ranking Member Lynch, and other members of the committee, thank you for inviting me to testify today. I have been writing about Guantanamo and the detainees held there for more than a decade and I visited the detention facility in 2008. I have reviewed most, if not almost all, of the publicly available files created by the U.S. government on the individual detainees, as well as the habeas decisions issued by the courts. This material constitutes thousands of pages of source files, which I have summarized in databases containing dozens of variables on most of the men who have been detained. The Guantanamo detainees are a regular part of my coverage at The Long War Journal, which was among the first publications to report that former detainee Ibrahim al Qosi, who is a senior al Qaeda figure, had rejoined the fight.

The key points in my testimony today are as follows:

Guantanamo has always posed risk management problems for the U.S. government. Early on, U.S. officials decided to divide the detainee population into categories based on risk. This process was incredibly difficult as it must take into account numerous factors, including sometimes murky, contradictory or uncorroborated intelligence. This process hasn’t been perfect, as some detainees were misidentified as low threats, transferred or released, and then rejoined the jihad in a significant capacity. In addition, in some cases detainees were misidentified as being more senior in jihadist organizations than they really were.

Even so, various bodies in the U.S. government have collected significant intelligence on most of the detainees. And the detainees’ dossiers have been reviewed multiple times by U.S. officials.

In January 2010, President Obama’s Guantanamo Review Task Force finished its work on the detainee population. It should be noted that the task force did not recommend any of the 240 detainees it evaluated be outright released.

Instead, the task force approved for “transfer,” or eventual transfer after “conditional detention,” 156 of the 240 detainees it reviewed — that is, nearly two-thirds of the detainee population. The task force made it clear that the term “transfer” was “used to mean release from confinement subject to appropriate security measures.” The term “release” was “used to mean release from confinement without the need for continuing security measures in the receiving country.” Again, no detainees were approved for outright release. In other words, the task force determined that there was at least some risk involved in the detainee transfers.

As of May 19, 2016, 80 detainees remain at Guantanamo. Only 15 of them were approved for transfer by President Obama’s task force. The majority of the detainees, 65 in all, were either referred for prosecution or slated for continued detention under the law of war (2001 Authorization for Use of Military Force). Therefore, the detainee population today is mostly comprised of detainees who President Obama’s own task force deemed too dangerous to transfer.

The Obama administration has established a Periodic Review Board (PRB) process to evaluate the cases of the 65 detainees previously deemed too dangerous to transfer. The PRB has issued 28 decisions thus far. The PRB has approved for transfer – again, subject to “appropriate security measures” – 21 of the 28 detainees. In some cases, detainees were approved for transfer by the PRB just months after the PRB itself ruled that continued detention remained necessary to mitigate the threat posed by the detainee. In the remaining seven instances, the PRB concluded that detention remained necessary.

In its most recent assessment, the Office of the Director of National Intelligence said that 204 former detainees were “confirmed” or “suspected” of reengaging in jihadist activities. The overwhelming majority of these recidivists were transferred or released by the Bush administration. But the number of recidivists transferred by the Obama administration has begun to climb as well, and it is likely only a matter of time until more of them are considered recidivists.

In sum, the U.S. government has taken on more and more risk in approving detainee transfers. The government seeks to mitigate this risk and some of its practices are likely somewhat effective (such as transferring detainees to countries that are not currently embroiled in jihadist insurgencies). Still, history shows that it is often difficult for the U.S. government to ensure that “appropriate security measures” are enacted by host countries.

Overview of the Guantanamo Detainee Population

President Obama’s Guantanamo Review Task Force noted in its final report, which was submitted in January 2010, that it had “reached decisions on the appropriate disposition of all 240 detainees” who were held as of January 2009 and “subject to” President Obama’s Executive Order. Below is a brief overview of the task force’s decisions for these 240 detainees. This is intended to be used as a comparison to the current population, which is also summarized below.

The task force approved 126 of the 240 detainees (52.5%) for transfer. Another 30 Yemeni detainees (12.5%) were placed in “conditional detention,” meaning they could be transferred if certain conditions were met. Therefore, the task force’s plan called for the eventual transfer of nearly two-thirds of the detainee population (65%). These detainees are represented in the green and yellow slices of the pie chart below.

The remaining detainees were either referred for prosecution (36 detainees, or 15% of the population) or slated for continued detention under the 2001 Authorization for Use of Military Force (48 detainees, or 20% of the detainees). Those referred for prosecution in either a court or a military commission are represented in the blue slice of the pie chart below. The detainees slated for continued law of war detention are represented in the red slice.

Although President Obama’s interagency task force approved nearly two-thirds of the detainees for transfer, its decisions did not mean that these same detainees were considered innocents who posed no threat. It is often reported that these same detainees were “cleared for release,” but that is not accurate. As the task force made clear, “appropriate security measures” needed to be put in place.

“It is important to emphasize that a decision to approve a detainee for transfer does not reflect a decision that the detainee poses no threat or no risk of recidivism,” the task force’s final report reads. The task force continued:

Rather, the decision reflects the best predictive judgment of senior government officials, based on the available information, that any threat posed by the detainee can be sufficiently mitigated through feasible and appropriate security measures in the receiving country. Indeed, all transfer decisions were made subject to the implementation of appropriate security measures in the receiving country, and extensive discussions are conducted with the receiving country about such security measures before any transfer is implemented.

In other words, many of the detainees approved for transfer were thought to pose at least some risk. 

The task force also explained that its transfer decisions did not reflect a conclusion that the detainees were improperly held in the first place. “It is also important to emphasize that a decision to approve a detainee for transfer does not equate to a judgment that the government lacked legal authority to hold the detainee,” the task force’s participants wrote. The task force continued:

To be sure, in some cases the review participants had concerns about the strength of the evidence against a detainee and the government’s ability to defend his detention in court, and considered those factors, among others, in deciding whether to approve the detainee for transfer. For many of the detainees approved for transfer, however, the review participants found there to be reliable evidence that the detainee had engaged in conduct providing a lawful basis for his detention. The review participants nonetheless considered these detainees appropriate candidates for transfer from a threat perspective, in light of their limited skills, minor organizational roles, or other factors.

As mentioned above, 30 Yemeni detainees were placed in “conditional detention.” Their status was more nuanced than much reporting lets on and they were not “cleared for release” as is sometimes reported. The task force found these Yemeni men could be transferred if the “security situation improves in Yemen,” “an appropriate rehabilitation program becomes available,” or “an appropriate third-country resettlement option becomes available.” The task force considered the Yemenis placed in “conditional detention” to be a lower risk than the detainees slated for continued detention under the 2001 AUMF, but they were also thought to be more of a threat than the Yemenis approved for outright transfer. Even if one of the three security conditions was “satisfied,” the task force said, the 29 Yemenis “approved for transfer would receive priority for any transfer options over the 30 Yemeni detainees approved for conditional detention.”

It should also be noted that the Bush administration approved some of these same detainees for transfer. The task force’s final report states that 59 of them “had been approved by the prior administration for transfer or release.” An additional 11 detainees were “ordered released by a federal court” as a result of habeas litigation. Thus, the task force reported, “a total of 70 detainees subject to the review were either approved for transfer during the prior administration or ordered released by a federal court.”

Given that the task force approved 156 detainees for transfer (including the Yemen detainees approved for eventual transfer after “conditional detention”), this means that President Obama’s interagency body approved an additional 86 detainees for transfer.

Overview of the current Guantanamo detainee population

Since the task force finished its final report, the detainee population has been reduced, primarily due to transfers, but also other reasons. Most of the detainees approved for transfer have been transferred.

80 detainees remain at Guantanamo today.

The pie chart above summarizes the detainee population as of May 19, 2016. Comparing it to the previous chart reveals how the situation has evolved.

Just four (4) of the remaining detainees were approved for transfer by the task force and 11 additional Yemenis were placed in “conditional detention.” This means that only 15 of the remaining 80 detainees (18.75%) were approved for transfer by the task force. The remaining 65 (81.25%) were either slated for prosecution or have been successfully prosecuted (32 detainees), or they were placed in continued detention under the 2001 AUMF (33 detainees).

The evolution of the detainee population is best seen by comparing the two charts. Whereas the green (approved for transfer) and yellow (conditional detention) slices dominated the pie in 2009, the blue and red slices account for most of the pie chart today.

According to the Guantanamo Review Task Force, the 33 detainees remaining at Guantanamo who were placed in continued detention under the laws of war “were determined to be too dangerous to transfer but not feasible for prosecution.”Detainees were placed in detention under the AUMF “only if (1) the detainee poses a national security threat that cannot be sufficiently mitigated through feasible and appropriate security measures; (2) prosecution of the detainee by the federal government is not feasible in any forum; and (3) continued detention without criminal charges is lawful.”

The decision to prosecute 32 of the remaining detainees was based on “standards used by federal prosecutors across the country.” The task force reported that cases were referred for prosecution “if the detainee’s conduct constitutes a federal offense and the potentially available admissible evidence will probably be sufficient to obtain and sustain a conviction—unless prosecution should be declined because no substantial federal interest would be served by prosecution.” The task force also listed “[k]ey factors in making this determination,” such as “the nature and seriousness of the offense; the detainee’s culpability in connection with the offense; the detainee’s willingness to cooperate in the investigation or prosecution of others; and the probable sentence or other consequences if the detainee is convicted.”

In sum, more than four out of every five (65 detainees) of the remaining 80 detainees were considered too dangerous to transfer by President Obama’s task force.

Overview of the Periodic Review Board (PRB) process

President Obama’s March 7, 2011 Executive Order (EO) 13567 established a Periodic Review Board (PRB) process “to review whether continued detention of particular individuals held at Guantanamo remains necessary to protect against a continuing significant threat to the security of the United States.” The PRB is “a discretionary, administrative interagency process” and its “decision-making panel consists of one senior official from the Departments of Defense, Homeland Security, Justice, and State; the Joint Staff, and the Office of the Director of National Intelligence.” There are four stages of review listed on the PRB’s website: “initial review,” “file review,” “full review,” and “subsequent full review.”

Thus far, 28 detainees have had their initial reviews completed. Four (4) of these 28 detainees subsequently had their “full review” completed as well. The decisions are publicly available on the PRB’s website. A review of these unclassified files revealed the following:

President Obama’s Guantanamo Review Task Force previously determined that 24 of these detainees should remain in continued detention under the 2001 AUMF. That is, these 24 detainees were considered “too dangerous to transfer but not feasible for prosecution.” The remaining four (4) detainees were referred for prosecution. Thus, the task force did not approve any of them for transfer.

In 21 of the 28 cases, the PRB determined that detention was “no longer necessary” or “does not remain necessary” to mitigate the threat posed by the individual detainee. This means that the PRB has approved 21 detainees for transfer who were previously denied transfer by the task force. Nine (9) of these 21 detainees have since been transferred.

In approving the transfer of these 21 detainees, the PRB notes that the “standard security assurances” or “appropriate security assurances” must be enacted by the receiving country, as determined by the Guantanamo Detainee Transfer Working Group. This language reflects the fact that the detainees are not being approved for outright release, and the PRB recognizes at least some level of risk is involved. The PRB’s decisions often cite reasons why the officials believe this risk can be mitigated (ranging from the detainee’s stated desire to start a new life, to medical conditions, to a family support network). Still, the language of the PRB’s decisions takes into account that the transfers are not, in general, risk free.

The PRB has approved for transfer all four detainees who have gone through the “full review” process. In each instance, not only was the detainee considered “too dangerous” to transfer by the Guantanamo Review Task Force, but he had also been previously denied transfer by the PRB itself. A brief overview of one of these decisions follows:

Abdel Malik Ahmed Abdel Wahab Al Rahabi (Internment Serial Number 37): On March 5, 2014, the PRB determined that “continued law of war detention of [Rahabi] remains necessary to protect against a continuing significant threat to the security of the United States.” The PRB cited Rahabi’s “significant ties to al-Qa’ida, including his past role as a bodyguard for Usama Bin Ladin and a prior relationship with the current amir of al-Qa’ida in the Arabian Peninsula.” In addition, the PRB cited Rahabi’s “experience fighting on the frontlines, possible selection for a hijacking plot, and significant training” as reasons for the PRB’s “concern.” In March 2014, the PRB did not think that the risks posed by Rahabi could be sufficiently mitigated. In December 2014, however, the PRB found the risks he presented could be “adequately mitigated” based on the testimony of Rahabi and his family members.

I have previously written about another one of these cases, that of Fayez al Kandari.The differences between the PRB’s decisions in 2014 and 2015 are striking. In July 2014, the PRB concluded that Kandari “almost certainly retains an extremist mindset and had close ties with high-level al Qaeda leaders in the past.” The PRB was also skeptical of Kuwait’s ability to handle a detainee such as Kandari, noting “a lack of history regarding the efficacy of the rehabilitation program Kuwait will implement for a detainee with his particular mindset.” The PRB said it “appreciate[d] the efforts of the Kuwaiti government and encourages the officials at the Al Salam Rehabilitation Center to continue to work with the detainee at Guantanamo.” In September 2015, however, the PRB claimed that Kandari had “demonstrated a willingness to examine his religious beliefs and engaged more openly with the Board.” The PRB “noted [Kandari’s] willingness to engage with Kuwaiti officials and rehabilitation center staff members, comply with security requirements, and disassociate with negative influences since his last hearing.” In 2015, the PRB also said that Kandari’s “threat can be adequately mitigated by the Kuwaiti government’s commitment to require and maintain the detainee’s participation in a rehabilitation program and to implement robust security measures to include monitoring and travel restrictions.”

In seven (7) of the 28 cases the PRB ruled that continued detention “remains necessary.” In some of the more recent cases, the PRB has cited the detainees’ ties to senior al Qaeda personnel who have plotted against the West.

The number of recidivists continues to rise

In March, the Office of the Director of National Intelligence (ODNI) released the most current statistics on recidivism. The figures are as of January 15, 2016.

The number of former Guantanamo detainees confirmed or suspected of rejoining the jihad has grown to 204, according to the ODNI. Nearly two-thirds of the jihadists, 128 in total, are at-large. The remaining 76 ex-detainees have been killed, died of natural causes, or were re-captured.

The overwhelming majority of the ex-detainees on the ODNI’s recidivist list, 185 out of 204 (91 percent), were transferred or released during the Bush administration. An additional 19 recidivists (7 confirmed, 12 suspected) were freed from Guantanamo during President Obama’s tenure.

The U.S. government’s list of one-time Guantanamo detainees who have rejoined the fight has grown significantly since 2008, when the first statistics were made public.

In June 2008, the Department of Defense reported that 37 former detainees were confirmed or suspected of returning to the fight. On Jan. 13, 2009, a Pentagon spokesman said that number had climbed to 61. In April 2009, the Pentagon told the press that same metric had risen further to 74.

The estimated number of recidivists more than doubled between April 2009 and October 2010, when the ODNI released an updated analysis saying that 150 former detainees were on the list. Since then, the ODNI’s assessment has climbed further, leading to the latest figure of 204 former detainees confirmed or suspected of rejoining jihadist networks.

The ODNI tracks former Guantanamo detainees who are involved in both “terrorist” and “insurgent” activities, including those thought to be “planning terrorist operations, conducting a terrorist or insurgent attack against Coalition or host-nation forces or civilians, conducting a suicide bombing, financing terrorist operations, recruiting others for terrorist operations, and arranging for movement of individuals involved in terrorist operations.”

The U.S. intelligence community’s assessment does not include those jihadists who have communicated with other former detainees or “past terrorist associates” about “non-nefarious activities.” The production of anti-American propaganda is not enough to be considered a recidivist either, according to the ODNI.

In order to be considered a “confirmed” recidivist, a “preponderance of information” must identify “a specific former GTMO detainee as directly involved in terrorist or insurgent activities.” The “suspected” category requires “[p]lausible but unverified or single-source reporting” that identifies a “specific former GTMO detainee” as being “directly involved in terrorist or insurgent activities.”

The current estimate includes 118 “confirmed” and 86 “suspected” recidivists, for a total of 204. Therefore, the reengagement rate is approximately 30 percent. However, this rate may be misleading.

It is likely that U.S. intelligence does not track all of the jihadists who were once held at Guantanamo, so even more former detainees could have rejoined terrorist or insurgent groups without the ODNI’s knowledge. There is also a lag time in the ODNI’s reporting. “A February 2010 review of GTMO detainees’ release dates compared to first reporting of confirmed or suspected reengagement shows about 2.5 years between leaving GTMO and the first identified reengagement reports,” the ODNI previously reported. It is possible, too, that some of the “suspected” recidivists aren’t really engaged in jihadist activities.

Former Guantanamo detainees have served jihadist groups in a variety of capacities, ranging from suicide bombers to leadership positions. Both the Taliban and al Qaeda have filled senior roles with alumni from the detention facility in Cuba.

Ibrahim al Qosi, who was held at Guantanamo from 2002 to 2014, reemerged as one of al Qaeda in the Arabian Peninsula’s (AQAP) most prominent figures late last year. Qosi received a favorable plea deal from prosecutors in the military commission system in 2010. Two years later, he was sent to his native country of Sudan. Since December 2015, AQAP has released several messages featuring Qosi.

Another Guantanamo alumnus, Hamed Abderrahaman Ahmed, was arrested by Spanish authorities in February and charged with running a recruiting network for the Islamic State. Ahmed was held in Cuba from February 2002 to February 2004, when he was transferred to Spain. He was allegedly operating a jihadist network in the city of Ceuta, which borders Morocco on the North African coast, at the time of his arrest.

The Obama administration notes that the number of confirmed or suspected recidivists transferred since early 2009 is much lower than the figure from the Bush years. This is, of course, true. One factor is that many of the Obama administration’s transfers have been to countries where the jihadists are not waging insurgencies. This is, on balance, a smart way to transfer otherwise risky detainees. It means that former detainees who may wish to rejoin the jihad will have a more difficult time doing so. We can hope that these detainees choose to follow a different path in the new country where they were placed. However, this may also only serve to delay some detainees’ recidivism. Given that President Obama’s task force previously determined that none of detainees should be outright released, and most of the remaining detainees were deemed too dangerous to transfer, we should expect the number of recidivists to continue to rise.