Ο δορυφόρος Λ-Sat (Hellenic Satellite)

Ο δορυφόρος Λ-Sat (Hellenic Satellite) δημιουργήθηκε με επικεφαλής τον Μεσσήνιο Περικλή Παπαδόπουλο και «πετάξε» με τον πύραυλο Antares, ο οποίος μετέφερε το σκάφος Cygnus με επιστημονικό και υποστηρικτικό υλικό στο Διεθνή Διαστημικό Σταθμό (ISS). Το Cygnus έφτασε στον ISS στις 16 Ιουλίου.

Στόχος του δορυφόρου είναι να μελετήσει την επίδραση της κοσμικής ακτινοβολίας στο υλικό γραφένιο, όταν αυτό βρίσκεται σε συνθήκες χαμηλής γήινης τροχιάς.

Τον Λ-sat σχεδίασε και κατασκεύασε η διεθνής ελληνική επιστημονική/φοιτητική ομάδα που φέρει την ονομασία «Lambda Team», με έδρα τη Silicon Valley, στην Καλιφόρνια και η οποία στην ιστοσελίδα της προβάλλει το σλόγκαν «Ελληνικά μυαλά με δράση» (Greek Minds at Work). Όπως ανέφερε ο δρ. Παπαδόπουλος σε συνεντεύξεις που είχε παραχωρήσει σε ομογενειακά ΜΜΕ, το κόστος του «μικροδορυφόρου» ήταν περίπου 100.000 δολάρια. Σύμφωνα με τον ίδιο, η αποστολή του θα συνέβαλε μεταξύ άλλων και στην προστασία ελληνικών εμπορικών πλοίων από πειρατείες.

NanoRacks-Λ-Sat Hellenic Satellite (NanoRacks-Λ-Sat ) – 10.01.14

NanoRacks-Λ-Sat Hellenic Satellite (NanoRacks-Λ-Sat) is the first space-based experiment to study how the harsh radiation and vacuum of space affects graphene, a single-layer sheet of carbon atoms important in nanotechnology applications. The satellite, the first to be designed and built by Greek scientists, also demonstrates a communications platform that monitors Greek merchant ships and their crews in real-time, aiming to improve maritime security and thwart piracy.

The following content was provided by Periklis Papadopoulos, Ph.D., and is maintained in a database by the ISS Program Science Office.

Experiment Details
OpNom NanoRacks CubeSat Deployer

Principal Investigator(s)

• Periklis Papadopoulos, Ph.D., Hellenic Space Initiative, Santa Clara, CA, United States

Co-Investigator(s)/Collaborator(s)
Information Pending
Developer(s)
Columbia University, New York, NY, United States
San Jose State University, San Jose, CA, United States
University of the Peloponnese, , , Greece
University of the Aegean, , , Greece
NanoRacks, LLC, Webster, TX, United States
Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)
Sponsoring Organization
National Laboratory (NL)
Research Benefits
Earth Benefits, Scientific Discovery, Space Exploration

Research Overview

•  NanoRacks-Λ-Sat Hellenic Satellite (NanoRacks-Λ-Sat) is the first-ever Hellenic satellite designed and built by Greek scientists.
•  NanoRacks-Λ-Sat demonstrates the first of-its kind space qualification of the nanotechnology material “Graphene” and its direct exposure to solar radiation and extreme space environments.
• NanoRacks-Λ-Sat aims to mitigate risk to Hellenic ships and their crews from piracies at sea by demonstrating a communications platform that monitors, with real-time positioning, Hellenic merchant ships for maritime security.
• Space qualification of innovative advanced three-fault tolerant spacecraft hardware is also a goal of NanoRacks-Λ-Sat.
• NanoRacks-Λ-Sat address Science Technology Engineering and Math (STEM) educational objectives.

Description
During deployment all of the NanoRacks-Λ-Sat Hellenic Satellite (NanoRacks-Λ-Sat) electronics are turned off.  Forty minutes past deployment into its in-space flight, an imbedded timer, activates satellite operations.  NanoRacks-Λ-Sat, following deployment from the International Space Station (ISS), has an initial altitude varying between an estimated 413 km apogee and 381 km perigee with inclination of 51.6 degrees.  As a safety precaution, the NanoRacks CubeSat Deployer containing the CubeSat is pointed behind the ISS and angled down 45 degrees, and ejected with a velocity of about 1 meter/second placing the CubeSat into a nearly circular orbit.  The NanoRacks-Λ-Sat communications platform consists of an Iridium Short Burst Data (SBD) modem that establishes in-space links with the Iridium constellation.  In addition, it uses a UHF receiver and transmitter for up-linking commands and downlinking flight data.  A custom designed power system and main computer, built to meet three-fault tolerant space qualification requirements, operate all NanoRacks-Λ-Sat electronics.  Following successful deployment of the NanoRacks-Λ-Sat, communications are established by means of the stensat, to downlink the Graphene experimental data.  The iridium communication platform is also enabled to transmit and collect the Automatic Identification System (AIS) data form the commercial ships globally.  The NanoRacks-Λ-Sat orbital lifetime is calculated to be approximately 174 days after launch; designed to de-orbit (as required by orbital debris requirements) and disintegrate during reentry at the end-of-life of its mission.