What is a Nebula?

A nebula is a giant cloud of dust and gas in space.

What is a Nebula?
Table of Contents

About Nebula:

  • A nebula is a giant cloud of dust and gas in space.
  • Some nebulae (more than one nebula) come from the gas and dust thrown out by the explosion of a dying star, such as a supernova.
  • Other nebulae are regions where new stars are beginning to form. For this reason, some nebulae are called “star nurseries.”
  • How do stars form in a nebula?
    • Nebulae are made of dust and gases—mostly hydrogen and helium.
    • The dust and gases in a nebula are very spread out, but gravity can slowly begin to pull together clumps of dust and gas.
    • As these clumps get bigger and bigger, their gravity gets stronger and stronger.
    • Eventually, the clump of dust and gas gets so big that it collapses from its own gravity. 
    • The collapse causes the material at the center of the cloud to heat up-and this hot core is the beginning of a star.
  • Nebulae existin the space between the stars—also known as interstellar space.
  • The closest known nebula to Earth is called the Helix Nebula. It is approximately 700 light-years away from Earth.
  • Nebulas come in many shapes and sizes and can be further divided into several subcategories, including planetary nebulas, supernova remnants, dark nebulas, and emission nebulas. 

Red Spider Nebula:

  • It is a planetary nebula located 3,000 light-years from Earth and can be found in the constellation of Sagittarius
  • It harbours one of the hottest stars known, which heats the gas around it to form shockwaves 62 billion miles (100 billion km) high. 

Q1: What is a Supernova?

A supernova is the name given to the cataclysmic explosion of a massive star. They are the largest explosion that takes place in space. It can emit more energy in a few seconds than our sun will radiate in its lifetime of billions of years. They’re also the primary source of heavy elements in the universe. On average, a supernova will occur once every 50 years in a galaxy the size of the Milky Way.

Source: Cosmic Spider: Nasa’s Hubble Captures Stunning Image Of The Red Spider Nebula’s Celestial Beauty

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