1. How many planets are in our solar system?
Answer: b) 8 (Mercury to Neptune; Pluto is a dwarf planet)
2. Which is the smallest planet in the solar system?
Answer: b) Mercury (Diameter: 4,900 km; Pluto is not a planet)
3. Which planet has the shortest day?
Answer: b) Jupiter (Rotates in 10 hours)
4. The hottest planet in the solar system is:
Answer: b) Venus (Due to CO₂ greenhouse effect)
5. Which planet is called "Earth's Twin"?
Answer: b) Venus (Similar size and mass)
6. Which planet has the most moons?
Answer: b) Saturn
7. Jupiter's largest moon is:
Answer: c) Ganymede (Largest in the solar system)
8. Which planet has prominent rings?
Answer: c) Saturn (Made of ice and dust)
9. The moon Titan orbits:
Answer: b) Saturn
10. Which planet has no moons?
Answer: c) Both a & b (Mercury & Venus are moonless)
11. The brightest star in the night sky is:
Answer: b) Sirius (Also called the "Dog Star")
12. A shooting star is a:
Answer: b) Meteor (Burns in Earth's mesosphere)
13. The asteroid belt is between:
Answer: b) Mars-Jupiter
14. Which is non-luminous?
Answer: b) Moon (Reflects sunlight)
15. The Kuiper Belt lies beyond:
Answer: d) Neptune
16. The Big Bang occurred ~_____ years ago.
Answer: b) 13.6 billion
17. The Nebular Theory explains:
Answer: b) Solar System origin (Proposed by Kant & Laplace)
18. Who discovered Uranus?
Answer: b) Herschel (1781)
19. Dark energy causes the universe to:
Answer: b) Expand (Accelerated expansion)
20. Cosmology is the study of:
Answer: c) Universe
21. Aditya-L1 studies:
Answer: b) Sun (ISRO's solar mission)
22. Pluto was reclassified in:
Answer: b) 2006 (By IAU)
23. Pandit Jasraj has a minor planet named after him called:
Answer: a) 300128 (From his birthdate: 28 Jan 1930)
24. Light from the Sun reaches Earth in ~____.
Answer: b) 8 min (8 min 20 sec at light speed)
25. The coldest planet is:
Answer: b) Uranus (Avg. temp: −224°C)
26. Venus rotates:
Answer: a) Clockwise (Retrograde rotation)
27. Mars' moons are:
Answer: b) Phobos & Deimos
28. Jupiter's Great Red Spot is a:
Answer: b) Storm (Giant anticyclone)
29. The Sun's outer layer is called:
Answer: b) Corona (Visible during eclipses)
30. Which planet is tilted 98°?
Answer: b) Uranus (Rolls on its side)
31. Terrestrial planets are:
Answer: a) Rocky & small (Mercury, Venus, Earth, Mars)
32. Jovian planets are:
Answer: c) Gaseous giants (Jupiter, Saturn, Uranus, Neptune)
33. Which planet is least dense?
Answer: b) Saturn (Could float in water!)
34. The "Green Planet" is:
Answer: b) Uranus (Methane gives greenish hue)
35. Neptune's discovery involved:
Answer: b) Math predictions (1846 by Galle & Le Verrier)
36. The closest star to Earth (after the Sun) is:
Answer: b) Proxima Centauri (4.24 light-years)
37. 1 light-year ≈ ____ km.
Answer: a) 9.46 trillion (9.46 × 10¹² km)
38. The largest constellation is:
Answer: b) Hydra
39. The Sun's core temperature is ~____.
Answer: c) 15.7 million K
40. The Milky Way is a:
Answer: b) Galaxy (Our home galaxy)
41. Which planet has sulfuric acid clouds?
Answer: b) Venus (H₂SO₄ clouds)
42. Olympus Mons, the largest volcano, is on:
Answer: b) Mars
43. The only planet with liquid water is:
Answer: a) Earth
44. Which planet has a "Great Dark Spot"?
Answer: b) Neptune (Similar to Jupiter's Great Red Spot)
45. The Sun's mass is ____% of the solar system's mass.
Answer: c) 99%
46. India's IIA (Indian Institute of Astrophysics) is headquartered in:
Answer: b) Bangalore
47. The Moon's gravity is ____ Earth's gravity.
Answer: b) 1/6th
48. Which planet is named after the Roman god of war?
Answer: b) Mars
49. Light from the Moon reaches Earth in ~____.
Answer: b) 1.26 sec
50. The farthest planet from the Sun is:
Answer: b) Neptune (Pluto is a dwarf planet)
51. Which planet is known as the "Rolling Planet" due to its extreme axial tilt?
Answer: b) Uranus (Tilted at 98°, rotating on its side)
52. The only moon in the solar system with a substantial atmosphere is:
Answer: c) Titan (Saturn's moon, with nitrogen-rich atmosphere)
53. Which gas dominates the atmosphere of Venus?
Answer: c) Carbon Dioxide (96.5%, causing extreme greenhouse effect)
54. The Cassini Division is a gap in the rings of:
Answer: b) Saturn (Discovered by Giovanni Cassini in 1675)
55. Which planet has the fastest winds in the solar system?
Answer: b) Neptune (Winds up to 2,100 km/h)
56. The "Oort Cloud" is hypothesized to be the source of:
Answer: b) Comets (Located far beyond the Kuiper Belt)
57. Which spacecraft discovered Uranus' rings in 1977?
Answer: a) Voyager 2 (First close-up images of Uranus)
58. The term "Goldilocks Zone" refers to:
Answer: b) The habitable zone around a star (Where liquid water can exist)
59. Which Indian mission studied Mars?
Answer: b) Mangalyaan (India's Mars Orbiter Mission, 2013)
60. The "Pillars of Creation" are part of which nebula?
Answer: b) Eagle Nebula (Famous Hubble Telescope image)