2.Question 2Why do we think that Enceladus seems less likely to have developed life than Europa (although, admittedly, we don't really know)?1 pointUnlike Europa, the ocean of Enceladus is not in contact with a rock core.Liquid water on Enceladus might be a recent phenomenon, giving insufficient time for life to evolveEnceladus does not have the complex organic materials known to be present on EuropaIt is difficult to imagine life evolving in an active plume.The low density of Enceladus suggests a rocky core which is too small to provide the heat required to have a liquid water layer.At the distance of Enceladus, the liquid water would be too cold for life

What makes Europa interesting to scientists?Group of answer choicesIt has a thick atmosphereIt has a liquid water ocean under its surfaceIt has many volcanoesThey have discovered people living there.

1.Question 1The existence of an ocean on Europa has been established from several different lines of evidence. First, spectroscopy of the surface shows that water ice is present. Second, gravitational measurements show that the upper layer of Europa is low density. The third line of evidence is the most convincing. What is this most convincing line of evidence?1 pointElectric currents within the ocean induce magnetic fields which have been measured.Many geological features suggest the presence of liquid underneath the ice.Europa has definitive evidence of plumes of water coming from the interior.When the surface ice shell of Europa flexes due to tidal forces, the magnitude of the effect is much larger than it would be for a thick solid shell.The faint hum of whale songs can be heard coming from underneath the iceEuropa has an oxygen atmosphere

Of Saturn’s 62 moons, the two most habitable for human life are Titan and Enceladus. They are very different from each other. For example, Titan is the second largest moon in our solar system, with a diameter of 2,575 kilometers. Tiny Enceladus has a diameter of only 500 kilometers. The atmosphere on Titan is thick and hazy, hiding surface features from most scientific instruments. Only its seasonal storms are visible. In contrast, the atmosphere on Enceladus is very thin. This means there is no air pressure or weather. However, scientists are better able to see what’s happening on its surface. Each of the moons  has a unique feature, as well. Titan is the only other place we know of in our solar system with liquids flowing across its surface. Enceladus doesn’t have liquids flowing on the surface, but there are geysers sending icy particles and water vapor into the sky at a speed of nearly 1,300 kilometers per hour.Which correct information from the text about Titan?Titan is the largest among all moons in solar system  blankTitan and Enceladus are more habitable than Saturn  blankTitan is more habitable because it has thick atmosphere and liquid on its surface  blankScientific instruments can see clearly the surface features of Titan  blank     √           Χ

Of Saturn’s 62 moons, the two most habitable for human life are Titan and Enceladus. They are very different from each other. For example, Titan is the second largest moon in our solar system, with a diameter of 2,575 kilometers. Tiny Enceladus has a diameter of only 500 kilometers. The atmosphere on Titan is thick and hazy, hiding surface features from most scientific instruments. Only its seasonal storms are visible. In contrast, the atmosphere on Enceladus is very thin. This means there is no air pressure or weather. However, scientists are better able to see what’s happening on its surface. Each of the moons  has a unique feature, as well. Titan is the only other place we know of in our solar system with liquids flowing across its surface. Enceladus doesn’t have liquids flowing on the surface, but there are geysers sending icy particles and water vapor into the sky at a speed of nearly 1,300 kilometers per hour.Which correct information from the text about Titan?Titan is the largest among all moons in solar system      Χ     Titan and Enceladus are more habitable than Saturn  blankTitan is more habitable because it has thick atmosphere and liquid on its surface  blankScientific instruments can see clearly the surface features of Titan      Χ          √           Χ

Is it likely that life ever existed on either Venus or Mars? Justify your answer in each case.