ObservingObserving thethe UniverseUniverse :: aa TravelTravel ThroughThrough SpaceSpace andand TimeTime

Enrico Flamini Agenzia Spaziale Italiana Tokyo 2009 When you rise your head to the night sky, what your eyes are observing may be astonishing. However it is only a small portion of the electromagnetic spectrum of the Universe: the visible . But any electromagnetic signal, indipendently from its frequency, travels at the speed of light. When we observe a star or a galaxy we see the photons produced at the moment of their production, their travel could have been incredibly long: it may be lasted millions or billions of years.

Looking at the sky at frequencies much higher then visible, like in the X-ray or gamma-ray energy range, we can observe the so called “violent sky” where extremely energetic fenoena occurs.like Pulsar, quasars, AGN, Supernova CosmicCosmic RaysRays:: messengersmessengers fromfrom thethe extremeextreme universeuniverse We cannot see the deep universe at E > few TeV, since photons are attenuated through →e± on the CMB + IR backgrounds. But using cosmic rays we should be able to ‘see’ up to ~ 6 x 1010 GeV before they get attenuated by other interaction.

Sources Sources → Primordial origin Primordial

7 Redshift z = 0 (t = 13.7 Gyr = now ! )

Going to a frequency lower then the visible light, and cooling down the instrument nearby absolute zero, it’s possible to observe signals produced millions or billions of years ago: we may travel near the instant of the formation of our universe: 13.7 By. Redshift z = 1.4 (t = 4.7 Gyr)

Credits A. Cimatti Univ. Bologna Redshift z = 5.7 (t = 1 Gyr)

Credits A. Cimatti Univ. Bologna Redshift z = 18.3 (t = 0.21 Gyr)

Credits A. Cimatti Univ. Bologna Herschel and Planck launch with Ariane V – May 2009 Planck first light yields promising results

Just above the atmosphere

Our Solar System The man made spacecraft at the edge of our Solar System

Voyager 1 OurOur LimitsLimits :age:age andand speedspeed CassiniCassini--HuygensHuygens NASANASA-- ESAESA-- ASIASI

• Antenna

SaturnSaturn beforebefore andand afterafter CassiniCassini

Before Cassini arrival 18 moons were Known, to date, 52 moons have been officially named. In alphabetic order, they are: Aegir, Albiorix, Anthe, Atlas, Bebhionn, Bergelmir, Bestla, Calypso, Daphnis, Dione, Enceladus, Epimetheus, Erriapus, Farbauti, Fenrir, Fornjot, Greip, Hati, Helene, Hyperion, Hyrokkin, Iapetus, Ijiraq, Janus, Jarnsaxa, Kari, Kiviuq, Loge, Methone, Mimas, Mundilfari, Narvi, Paaliaq, Pallene, Pan, Pandora, Phoebe, Polydeuces, Prometheus, Rhea, Siarnaq, Skadi, Skoll, Surtur, Suttung, Tarqeq, Tarvos, Telesto, Tethys, Thrym, Titan and Ymir.

EnceladusEnceladus EnceladusEnceladus The Huygens descent on Titan NorthNorth PolarPolar RegionRegion Mosaic:Mosaic: EthaneEthane andand MethaneMethane LakesLakes Jupiter EUROPAEUROPA Mars For Robots Now….. tomorrow? Viking Lander 1

Impact of dust on atmospheric temperatures: -can reach 80 K during dust storm ! - can produce temperature inversionE. Flamini near surface E. Flamini Formation of water ice frost on the surface (Viking lander 2)

E. Flamini

PhoenixPhoenix MarsMars 3328 - 2202 2202 flight dir.

3328 flight dir.

Exomars the European Mars Explorer The Sample return

No future without imagination !

Thanks for you attention