The question asks for a general term that encompasses various objects observed in the sky, such as stars, planets, and the moon. We need to identify the term that broadly classifies all natural objects existing in outer space.
B) Celestial objects. This is the correct term because it broadly refers to any natural object or entity that exists in outer space, including stars, planets, moons, asteroids, comets, and galaxies.
The question asks to identify the correct statements regarding ISRO's Mangalyaan mission. We need to evaluate each statement based on factual information about the Mars Orbiter Mission (MOM).
C) 1 and 3 only
Statements 1 and 3 are factually correct, while statement 2 is incorrect.
The question asks for the specific field of study that deals with celestial objects and related phenomena. We need to identify the correct scientific discipline from the given options.
Correct Option: A) Astronomy is the scientific discipline that studies celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside Earth's atmosphere (such as supernovae, gamma-ray bursts, and cosmic microwave background radiation).
The question asks for the scientific term used to describe the changing appearance of the Moon's illuminated portion as observed from Earth over the course of a month. This phenomenon is a fundamental concept in astronomy.
Correct Option: C) Phases of the moon. The term "phases of the moon" precisely describes the different shapes of the sunlit portion of the Moon as seen from Earth over approximately a month. These phases include the New Moon, Crescent, Quarter, Gibbous, and Full Moon, which occur in a predictable cycle.
The question asks about the phases of the moon and the duration of its cycle. We need to evaluate each statement based on our understanding of lunar phases and orbital mechanics.
C) (i) and (ii) only. Both statements (i) and (ii) accurately describe the waxing and waning phases of the moon, respectively.
The question asks to identify the motion of the Earth that corresponds to one rotation of the Moon on its axis. This requires understanding the synchronized motions of the Moon.
B) Revolution — The Moon's period of rotation on its axis is approximately 27.3 days, which is almost exactly the same as its orbital period (revolution) around the Earth. This is why we always see the same face of the Moon.