10 most difficult universe riddles A list of universe related questions that are most often answered incorrectly Astronomy quiz The celestial sphere is divided into ...88 constellations. The current list of 88 constellations recognized by the International Astronomical Union since 1922 is based on the 48 listed by Ptolemy in his Almagest in the 2nd century, with early modern modifications and additions In 1930, the boundaries between the 88 constellations were devised by Eugène Delporte along vertical and horizontal lines of right ascension and declination.very hard 23% 22 constellations22 constellations17%44 constellations44 constellations34%66 constellations66 constellations24%88 constellations88 constellations23%Created by: Tschuka . Statistics based on 1312 answers in 2 languages »astronomy riddles » What was the most beautiful comet of the second half of the twentieth century, with two tails visible to the naked eye?Comet Hale-Bopp. Hale–Bopp was discovered on July 23, 1995 separately by Alan Hale and Thomas Bopp prior to it becoming naked-eye visible on Earth. Comet Hale-Boppit was visible to the naked eye for a record 18 months, twice as long as the previous record holder, the Great Comet of 1811. Accordingly, Hale–Bopp was dubbed the Great Comet of 1997.very hard 25% Halley's cometHalley's comet59%Comet McNaughtComet McNaught6%Comet Hale-BoppComet Hale-Bopp25%There was no such cometThere was no such comet7%Created by: Tschuka . Statistics based on 1128 answers in 2 languages »space riddles » Which of the constellations is the largest? (seen from the ground) Hydra is the largest of the 88 modern constellations, measuring 1303 square degrees. Also one of the longest at over 100 degrees, It has a long history, having been included among the 48 constellations listed by the 2nd century astronomer Ptolemy. It is commonly represented as a water snake. very hard 26% Big DogBig Dog10%HydraHydra26%OrionOrion25%Great BearGreat Bear37%Created by: Tschuka . Statistics based on 1449 answers in 2 languages »stars riddles » The idea that the nascent universe passes through the phase of exponential expansion, which was driven by the positive density of vacuum energy, is called;Cosmic inflation. Alan Guth formally proposed the idea of cosmic inflation in 1981, the idea that the nascent universe passed through a phase of exponential expansion that was driven by a positive vacuum energy density (negative vacuum pressure).very hard 27% Cosmic inflationCosmic inflation27%Grand unification theoryGrand unification theory25%Theory of SupersymmetryTheory of Supersymmetry15%All answers are correct.All answers are correct.31%Created by: Tschuka . Statistics based on 4667 answers in 2 languages »physics riddles » Which of the following cosmic structures is the largest?Galaxy filaments are the largest known structures in the universe. They group galaxy superclusters, which in turn are formed by cluster composed of galaxies. Hercules–Corona Borealis Great Wall is considered the largest known structure of Universe. It is estimated to span 10 billions light years. very hard 32% GalaxyGalaxy25%Galaxy filamentGalaxy filament32%Galaxy clusterGalaxy cluster3%SuperclusterSupercluster39%Created by: smyru. Statistics based on 4102 answers in 2 languages »astronomy riddles » What is the source of the most powerful release of energy in the universe, second in scale only to the Big Bang?Gamma-ray bursts are the brightest in the universe, even brighter than the glare of quasars, second only to the brightness and power of the Big Bang. It is believed that arise during disruption of stars by black holes.very hard 33% supermassive starssupermassive stars4%quasarsquasars19%gamma-ray burstgamma-ray burst33%supernovasupernova42%Created by: Krzysztof Moskal. Statistics based on 4070 answers in 2 languages »astronomy riddles » The Sun activity increases during every ...11 years. Basic period of time in which the activity of Sun is increasing is 11 years. It is visible on the chart.very hard 39% 5 years5 years13%11 years11 years39%22 years22 years18%1300 years1300 years28%Created by: Katarzyna Dąbrowska. Statistics based on 5210 answers in 2 languages »Sun riddles » 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.hard 42% supergiant starssupergiant stars7%novaenovae3%supernovaesupernovae46%quasarsquasars42%Created by: globalquiz.org. Statistics based on 12463 answers in 2 languages »time riddles » What object collided with Earth according to the giant impact hypothesis?A planet. According to the giant impact hypothesis Earth once collided with a planet of Mars size usually referred to as Theia, a titaness of Greek mythology, mother of Selene - Moon goddess, which is to reflect the believe the collision was an origin of the Moon. hard 47% a cometa comet10%a moona moon8%an asteroid an asteroid 33%a planeta planet47%Created by: smyru. Statistics based on 7647 answers in 2 languages »Earth riddles » What properties do sunspots have?Lower temperature and strong magnetic field. Sunspots are temporary phenomena on the Sun's photosphere that appear as spots darker than the surrounding areas. They are regions of reduced surface temperature caused by concentrations of magnetic field flux that inhibit convection.hard 47% Lower temperature and strong electric fieldLower temperature and strong electric field12%Higher temperatureHigher temperature20%Lower temperature and strong magnetic fieldLower temperature and strong magnetic field47%These are holes in the photosphereThese are holes in the photosphere19%Created by: Tschuka . Statistics based on 1290 answers in 2 languages »astronomy riddles » Play astronomy quiz and see all the questions.