10 most difficult Sun riddles A list of Sun related questions that are most often answered incorrectly Astronomy quiz When was the photovoltaic cell invented?1839. The first experimental photovoltaic cell has been built by Edmund Becquerel, French physicist aged 19 at the time, in his father garage in 1839. In 1883 Charles Fritts created the first solid state cell. very hard 22% 1839183922%1883188332%1946194626%1958195818%Created by: smyru. Statistics based on 194 answers in 3 languages »energy riddles » What is the temperature of the center of the Sun?16 million degrees Celsius. The surface temperature is only 5500 degrees Celsius.very hard 24% 16 thousand degrees Celsius16 thousand degrees Celsius19%16 million degrees Celsius16 million degrees Celsius24%16 billion degrees Celsius16 billion degrees Celsius35%16 trillion degrees Celsius16 trillion degrees Celsius20%Created by: Tschuka. Statistics based on 513 answers in 3 languages »temperatures riddles » In what period of time does the Sun make a full turn around the center of the Milky Way?Within every 225 million years. The sun performs a full turn around the center of our galaxy during 225 million years.very hard 27% within every 225 million yearswithin every 225 million years27%within 250 million yearswithin 250 million years32%within 300 million yearswithin 300 million years23%within 350 million yearswithin 350 million years16%Created by: Tschuka. Statistics based on 833 answers in 3 languages »time riddles » How is the visible surface of the Sun called?Photosphere. The photosphere is a layer below which the Sun becomes opaque to visible light. It is tens to hundreds of kilometers thick, and is slightly less opaque than air on Earth. Because the upper part of the photosphere is cooler than the lower part, an image of the Sun appears brighter in the center than on the edge or limb of the solar disk, in a phenomenon known as limb darkening.very hard 32% chromospherechromosphere16%coronacorona38%stratospherestratosphere11%photospherephotosphere32%Created by: Ninjai. Statistics based on 2930 answers in 3 languages »universe riddles » The bright circle around the Sun seen in the picture is known as a halo. What causes it?Refraction of light in ice crystals. Halo is the name for a family of optical phenomena produced by light interacting with ice crystals suspended in the atmosphere. Halos can have many forms, ranging from colored or white rings to arcs and spots in the sky. Among the best known halo types are the circular halo (properly called the 22° halo), Other common optical phenomena involving water droplets rather than ice crystals include the glory and the rainbow. very hard 36% refraction of light in ice crystalsrefraction of light in ice crystals36%refraction in the lens of the eye or lensrefraction in the lens of the eye or lens31%refraction of light in water dropsrefraction of light in water drops25%reflections from the water surfacereflections from the water surface6%Created by: Tschuka. Statistics based on 9924 answers in 3 languages »atmosphere riddles » Which telescope was designed to detect exoplanets?The Kepler Space Telescope. Kepler is a space observatory launched by NASA to discover Earth-size planets orbiting other stars. Named after astronomer Johannes Kepler, the spacecraft was launched on March , 2009, in. Designed to survey a portion of our region of the Milky Way to discover Earth-size exoplanets in or near habitable zones and estimate how many of the billions of stars in the Milky Way have such planets, very hard 38% The Kepler Space TelescopeThe Kepler Space Telescope38%Space Chandra TelescopeSpace Chandra Telescope7%The Hubble Space TelescopeThe Hubble Space Telescope41%Atacama Large Millimeter / submillimeter Array (ALMA)Atacama Large Millimeter / submillimeter Array (ALMA)12%Created by: Tschuka. Statistics based on 3107 answers in 2 languages »astronautics 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 5563 answers in 3 languages »astronomy riddles » What type of plasma is Sun composed of?Hot. The Sun is a nearly perfect sphere of hot plasma, with internal convective motion that generates a magnetic field via a dynamo process. Hot plasmas (thermal plasmas) have electrons and the heavy particles at the same temperature, i.e. they are in thermal equilibrium with each other. Cold plasmas (nonthermal plasmas) on the other hand have the ions and neutrals at a much lower temperature, whereas electrons are much "hotter".hard 41% coldcold10%hothot41%ultracoldultracold20%none of the abovenone of the above27%Created by: Ninjai. Statistics based on 4695 answers in 2 languages »light riddles » What is larger on the sky: the Moon or the Sun? (by apparent size)Sometimes the Moon, sometimes the Sun. The Moon's orbit is elliptical, and its apparent diameter varies by 10%. This is why both total eclipses (if the Moon is larger) and annular eclipses (if the Sun is larger) happen.hard 43% the Sunthe Sun18%the Moonthe Moon23%both are identicalboth are identical14%sometimes the Moon, sometimes the Sunsometimes the Moon, sometimes the Sun43%Created by: pan Krzyżówka. Statistics based on 11849 answers in 3 languages »sky riddles » In which month is the Earth closest to the Sun?In January. Earth's perihelion occurs around January 3, and the aphelion around July 4. The distance change is about 3.5%, which gives 6.9% increase in solar energy reaching the Earth at perihelion relative to aphelion. Since the southern hemisphere is tilted toward the perihelion, the southern hemisphere receives more energy from the Sun than does the northern over the course of a year. hard 44% in Januaryin January44%in Marchin March6%in Junein June32%there is no differencethere is no difference15%Created by: globalquiz.org. Statistics based on 15447 answers in 5 languages »hard simple questions riddles » Play astronomy quiz and see all the questions.