Space questions This is a list of recently added questions about space. What is entropy?It is a measure of the disorder in a closed system. It is a measure of the disorder or randomness in a closed system. The second law of thermodynamics states that if isolated thermodynamic system spontaneously evolves into another state of equilibrium, its entropy will always increase. The term was invented by Rudolf Clausius.Created by: Władysław Pękalaphysics riddles »hard 49% It is a measure of the disorder in a closed system.It is a measure of the disorder in a closed system.1128It is a measure of system's sizeIt is a measure of system's size258Both answers are correctBoth answers are correct467None of above answersNone of above answers441 Which planet of the solar system has the smallest surface?Mercury has a surface of 75x10^6 km^2, which is equal to 14,7% of Earth' surface.Created by: lanusienkaplanets riddles »easy 77% MercuryMercury2221VenusVenus267EarthEarth126MarsMars243 What is the name of first in history cosmic tourist (astrotourist)?Dennis Tito. Dennis Anthony Tito is an American engineer and multimillionaire, most widely known as the first space tourist to fund his own trip into space. Tito paid a reported $20 million to the Russian Federal Space Agency.Created by: Paweł Kołodziejczyktourism riddles »very hard 39% Neil Alden ArmstrongNeil Alden Armstrong1018Guy LalibertéGuy Laliberté410Dennis TitoDennis Tito1312Richard GarriottRichard Garriott619 How many times is Jupiter's volume larger than Earth's volume?1,321 times. Jupiter is so big, that it is almost the size of a star. The smallest known red dwarf is just 16 percent larger in diameter than Jupiter.Created by: K.R.A.C.Solar System riddles »hard 56% 800 times800 times8251,321 times1,321 times265050 times50 times42410,000 times10,000 times793 What are the most luminous objects in the universe?Quasars. A quasar is an extremely energetic source of radiation powered by accretion disc around galaxy's central supermassive black hole. Quasars were much more common in the early universe, as all known quasars are extremely distant.Created by: globalquiz.orglight riddles »hard 40% supergiant starssupergiant stars568novaenovae263supernovaesupernovae2983quasarsquasars2642 How long did it take Apollo 11 flight to reach the Moon? 3 days. It took 1 minute of flight to reach Mach 1 and 12 minutes to enter Earth's orbit. After one and a half orbits, the third-stage engine pushed the spacecraft onto its three-day long travel to the Moon.Created by: Hitter smasherrockets riddles »average 61% 30 minutes30 minutes3263 hours3 hours11323 days3 days444330 days30 days1320 Play astronomy quiz and see all the questions.