Europa

          Europa is the moon of Jupiter,it is slightly smaller than our moon, but still is the 6th largest moon.It is made of silicate and has a layer of frozen water and has liquid under the frozen water.

This was discovered because of the fleeting plumes of liquid. As it has liquid which is rich in minerals  in it,it may be  home to many sea life. The liquid under the ice layer remains liquid because of the tidal flexing which is similar to plate tectonics.

     The Galileo mission, launched in 1989, provided the bulk of current data on Europa. No spacecraft has yet landed on Europa, but its intriguing characteristics have led to several ambitious exploration proposals. The European Space Agency's Jupiter Icy Moon Explorer (JUICE) is a mission to Europa that is due to launch in 2022. NASA's proposed Europa Clipper mission may be launched in the mid-2020 s.                                                                                                                                                                                                                       
                         

1996 by Galileo spacecraft. Discovered by Galileo Galilei Simon Marius Discovery date 8 January 1610[1] Designations Alternative names Jupiter II Adjectives Europan Orbital characteristics[3] Epoch 8 January 2004 Periapsis 664862 km[a] Apoapsis 676938 km[b] Mean orbitradius 670900 km[2] Eccentricity 0.009[2] Orbital period 3.551181 d[2] Averageorbital speed 13.740 km/s[2] Inclination 0.470° (to Jupiter's equator) 1.791° (to the ecliptic)[2] Satellite of Jupiter Physical characteristics Mean radius 1560.8±0.5 km (0.245 Earths)[4] Surface area 3.09×107 km2 (0.061 Earths)[c] Volume 1.593×1010 km3 (0.015 Earths)[d] Mass (4.799844±0.000013)×1022 kg(0.008 Earths)[4] Mean density 3.013±0.005 g/cm3[4] Surface gravity 1.314 m/s2 (0.134 g)[e] Escape velocity 2.025 km/s[f] Rotation period Synchronous[5] Axial tilt 0.1°[6] Albedo 0.67 ± 0.03[4] Surface temp. min mean max Surface ≈ 50 K[7] 102 K (−171.15°C) 125 K Apparent magnitude 5.29 (opposition)[4] Atmosphere Surface pressure 0.1 µPa (10−12 bar)[8]

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