Astronomy and Cosmology

The distance between stars is measured in light-years, which is the distance light travels in one year. Sound doesn't travel through the vacuum of space, and electromagnetic waves include light itself.

Stars are primarily composed of plasma, which is the fourth state of matter. At the extremely high temperatures in stars, gas becomes ionized and exists as plasma.

The Milky Way Galaxy is classified as a spiral galaxy. It has a barred spiral structure with distinct spiral arms emanating from a central bar.

Active galaxies are believed to have supermassive black holes at their centers. The enormous energy output from active galactic nuclei is best explained by matter accreting onto these black holes.

The Andromeda Galaxy is designated as Messier 31 or M31 in Charles Messier's catalog of astronomical objects. It is the nearest major spiral galaxy to the Milky Way.

The Andromeda Galaxy is the nearest major galaxy to the Milky Way. While the Large Magellanic Cloud is closer, it is a satellite dwarf galaxy, not a major galaxy like Andromeda.

The Big Bang produced primarily hydrogen and helium, the two lightest elements. These formed from the cooling of the initial hot, dense state of the universe. Heavier elements were later produced in stars.

Comet McNaught (C/2006 P1) was the brightest comet visible from Earth in over 30 years when it appeared in early 2007. It reached magnitude -5, making it visible even during daylight hours, and was particularly spectacular in the southern hemisphere.

Comet McNaught (C/2006 P1) was the brightest comet visible from Earth in over 30 years when it appeared in early 2007. It reached magnitude -5, making it visible even during daylight hours, and was particularly spectacular in the southern hemisphere.

Splendor, Karizma, and CBZ are all motorcycles from Hero/Hero Honda. Pulsar is from Bajaj Auto, making it the odd one out by manufacturer.

Brown dwarfs are substellar objects that are not massive enough to sustain hydrogen fusion in their cores (unlike main sequence stars) but are more massive than planets. They're essentially 'failed stars' - gas masses that never ignited. Black holes are collapsed stellar remnants, nebulas are gas clouds, and asteroids are rocky bodies.

A pulsar is a highly magnetized, rotating neutron star that emits beams of electromagnetic radiation, giving the appearance of pulsing radiation. Meteorites are space rocks that reach Earth's surface, nebulae are clouds of gas and dust, and black holes absorb all light.

Runaway stars are stars moving through space at unusually high velocities, often exceeding 200 km/s, typically ejected from their original systems. The other options are humorous or made-up names, not astronomical terms.

A pulsar is a highly magnetized rotating neutron star that emits beams of electromagnetic radiation from its magnetic poles, appearing as regular pulses of energy when observed. They were first discovered in 1967 and are some of the most energetic objects in the universe. Meteorites and nebulae don't emit excessive radiation, while black holes absorb light rather than emit it.

Runaway stars are stars that move at exceptionally high velocities through space, often exceeding 200 km per second. They are typically ejected from their original locations due to gravitational interactions or supernova explosions. The term is used in astronomy for these high-velocity stellar objects.