nebulae, nebulæ, or nebulas) is an interstellar cloud of dust, hydrogen, helium and other ionized gases. Originally, nebula was a name for any diffuse astronomical object, including galaxies beyond the Milky Way. The Andromeda Galaxy, for instance, was once referred to as the Andromeda Nebula (and spiral galaxies in general as "spiral nebulae") before the true nature of galaxies was confirmed in the early 20th century by Vesto Slipher, Edwin Hubble and others.
Most nebulae are of vast size, even hundreds of light years in diameter.[3] Although denser than the space surrounding them, most nebulae are far less dense than any vacuum created on Earth – a nebular cloud the size of the Earth would have a total mass of only a few kilograms. Many nebulae are visible due to their fluorescence caused by the embedded hot stars, while others are so diffuse they can only be detected with long exposures and special filters. Some nebulae, are variably illuminated by T Tauri variable stars. Nebulae are often star-forming regions, such as in the "Pillars of Creation" in the Eagle Nebula. In these regions the formations of gas, dust, and other materials "clump" together to form denser regions, which attract further matter, and eventually will become dense enough to form stars. The remaining material is then believed to form planets and other planetary system objects.
The range of objects called nebula are very diverse, have diverse origins, and final ends.
Contents <span> [hide] </span><span><span>1Observational history</span><span>2Formation</span><span><span>3Types of nebulae</span><span><span>3.1Classical types</span><span>3.2Diffuse nebulae</span><span><span>3.3Planetary nebulae</span><span>3.3.1Protoplanetary nebula</span></span><span>3.4Supernova remnants</span></span></span><span><span>4Notable named nebulae</span><span>4.1Nebula catalogs</span></span><span>5See also</span><span>6References</span><span>7<span>External links
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Thermodynamics is the branch of physical science which deals with the relationship between heat and other forms of energy like chemical energy, mechanical or electrical. Here are examples of thermodynamics that are commonly seen in everyday living: When you accidentally wrecked or bumped your car, you came out alive and just slightly hurt, because it was the car that that absorbed the energy of the impact. Another example is that, during cooking. When you are cooking, the heat is being transferred to the pan and then to the food that you are cooking.
the purpose of fuses and circuit breakers is (first answer)
Answer:
<em>Force B</em>
Explanation:
<u>Friction Force
</u>
It's a force that appears when an object is tried to move on a rough surface. There are two cases: when the object is at rest, we have the friction static coefficient and when the object is already moving, we have the dynamic coefficient. The static coefficient is usually greater than the second because it's harder to overcome the friction when the object is at rest.
We are told that John pushes the bed to the left with enough force to overcome the force of friction. If the movement is intended to be to the left side, the friction force appears to the right, since it always opposes to the movement. Thus the force B is the one who represents the friction force in this situation
D. Yield signs is the answer
