Context:
Eta Aquariid meteor shower, associated with Halley’s Comet, occurred on the 5th and 6th of May 2024.
Eta Aquariid Meteor Shower:
- Occurs annually during early May characterised by its rapid meteors.
- Origin – From the debris left behind by Comet Halley, resulting in long-lasting, glowing tails.
- Visibility – 30-40 Eta Aquarid meteors per hour during peak (particularly from the Southern Hemisphere)
- Southern Hemisphere – It offers a more favourable viewing experience due to the higher position of the constellation Aquarius, the radiant of the meteor shower.
- Northern Hemisphere – Observers may witness “Earthgrazers”, long meteors skimming the horizon.
Comets:
- Comets: These are icy, early solar system remnants made of dust and rock, orbiting the Sun in elliptical paths.
- Behavior: When heated by the Sun, comets emit gas and dust, forming a glowing head and tail.
- Locations: NASA states that billions of comets orbit beyond Neptune, in the Kuiper Belt and distant Oort cloud.
Meteors are small particles of dust or rock, originating from comets or fragmented asteroids. They create short-lived streaks of light as they burn upon entering Earth’s atmosphere.
Related Important Terms:
- Meteoroid and Meteorite:
- Meteoroids are space rocks, varying from dust grains to small asteroids.
- They become meteors when entering Earth’s atmosphere at high speed and burning up.
- If a meteoroid reaches the ground without completely burning up, it’s called a meteorite.
- Constellation:
- A recognizable pattern of stars in the night sky.
- They have been used for navigation, storytelling, and timekeeping for centuries.
- Kuiper Belt:
- A region beyond Neptune’s orbit, home to thousands of icy objects.
- Includes dwarf planets like Pluto, comets, and Kuiper Belt Objects (KBOs).
- Oort Cloud:
- A giant, spherical cloud of icy objects that surrounds the solar system at a much greater distance than the Kuiper Belt.
- The source of long-period comets.
Source: Indian Express
Previous Year Question
Consider the following pairs:
Objects in space: Description
1. Cepheids: Giant clouds of dust and gas in space
2. Nebulae: Stars which brighten and dim periodically
3. Pulsars: Neutron stars that are formed when massive stars run out of fuel and collapse
How many of the above pairs are correctly matched?
[UPSC Civil Services Exam – 2023 Prelims]
(a) Only one
(b) Only two
(c) All three
(d) None
Answer: (a)
Explanation:
Pair 1 and 2 are not correctly matched.
Cepheids are actually a type of variable star that brightens and dims periodically, not giant clouds of dust and gas in space.
Nebulae are vast clouds of gas and dust in space, not stars that brighten and dim periodically.
