Context
Astronomers have recently identified ten unusual neutron stars near the center of the Milky Way.
About Neutron Stars
- Extremely dense and compact celestial objects formed from the collapse of a massive star’s core after it runs out of fuel.
- During this collapse, protons and electrons are crushed together, forming neutrons.
- If the collapsing core’s mass is between 1 and 3 solar masses, the newly-created neutrons can halt further collapse, resulting in a neutron star.
- Cores with masses exceeding this range continue to collapse into stellar-mass black holes .
- Are scattered throughout the galaxy in regions where stars are found.
- They can exist alone or in binary systems with a companion star.
- Have a diameter of about 20 km (12 miles).
- Mass ranging from 1.18 to 1.97 times that of the Sun, with most being around 1.35 times the Sun’s mass.
- Many neutron stars are likely undetectable due to insufficient radiation emission.
- Observational Phenomena of Neutron Stars
- Pulsars:Rotating neutron stars emitting regular radiation pulses (milliseconds to seconds).
- Rotating Radio Transients (RRATs):Emit single radio bursts irregularly (intervals: 4 minutes to 3 hours).
- Magnetars:Neutron stars with ultrahigh magnetic fields; emit X-ray and gamma-ray bursts.
Types of Stars- Based on Size and Luminosity:
- Main Sequence Stars: Most stars, including our Sun, fall into this category. They fuse hydrogen into helium in their cores.
- Giants and Supergiants: These are much larger and brighter than main sequence stars. They’ve exhausted their core hydrogen and are fusing heavier elements.
- White Dwarfs: These are small, dense remnants of stars that have exhausted their nuclear fuel.
- Neutron Stars: Extremely dense, small stars formed from the cores of massive stars after supernova explosions.
- Black Holes: Objects with such strong gravity that nothing, not even light, can escape.
Source:
Space.com
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
[UPSC Civil Services Exam – 2023 Prelims]
How many of the above pairs are correctly matched? (a) Only one
(b) Only two
(c) All three
(d) None
Answer: (d)
