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Nebula

(Last edited: Monday, 5 June 2023, 1:56 PM)



Source

Kirk, A. (2015, April 25). The Mighty Orion Nebula from New Zealand. flickr. https://www.flickr.com/photos/67481624@N05/17243621226

Short Definition: 

Any kind of giant cloud that includes miscellaneous gas and dust; especially hydrogen, cosmic dust, and helium located in outer space.

Detailed Definition

As the basic components of galaxies, nebulae were stars before they formed. During the formation phase of these stars, the gases released into space initiate a fusion reaction with hydrogen atoms and form the foundations of a new star. Thus, the universe continues to expand.

Etymology:  

Ancient Greek (νεφέλη nephélē): Cloud

Sample Sentences:

'Today the term nebula generally refers exclusively to the interstellar medium.'

'A nebula that is visible to the human eye from Earth would appear larger, but no brighter, from close by.'

Translations of Terms/Concepts into Partner Languages:

French:

Nébuleuse

Italian:

Nebulosa

German:

Nebel

Polish:

Mgławica

Turkish:

Nebula

Links to Videos/Articles:

https://spacecenter.org/what-is-a-nebula/

https://spaceplace.nasa.gov/nebula/en/

https://www.space.com/nebula-definition-types

https://www.britannica.com/science/nebula


Neutron star

(Last edited: Friday, 28 April 2023, 6:09 PM)


Short Definition:

A Neutron star is a celestial body and is the collapsed core of a massive supergiant star that had a total mass of about 10-25 solar masses. Compared to other stellar objects, they are much smaller and much denser. Not counting black holes or hypothetical stellar objects, they are the densest stellar object in the universe.

Detailed Definition:

A Neutron stars is a stellar object, which is only a few kilometres in diameter, but has the mass of a star. So even compared to others stellar objects they have a mind-boggling density and are even so dense, that they are on the cusp of becoming a black hole. Stars hold an equilibrium between the force of gravity forcing plasma inwards, which in turn enables fusion of hydrogen to helium, and this releases energy that pushes outwards. So the equilibrium is directly linked to the amount of hydrogen available in stars. Breaking this equilibrium in our sun would result in it transforming to a red giant and then to a white dwarf. In those massive supergiant stars, gravity will prevail and will compress the core to the density of an atomic nucleus, which in turn forces heavier elements to fuse, and thus the outer layer will get bigger by a factor of x100. After a time the heavier elements are fused to iron and can not be fused any more, so the fusion activity will cease, and the star will collapse to its core. Electrons and Protons will be forced into each other and form Neutrons as dense as in atomic nuclei, where nuclei are so densely packed, they form a layer that is called nuclear pasta. Another interesting property is that they are spinning really fast, which empowers their magnet fields and gives them the strongest magnet field in our universe.

Etymology:

Neutron from Ne and uterà neutral +on ending from ion subatomic particle suffix

Star from Proto-Indo-European roothstḗr

Sample Sentence(s):

The physics in the core of the Neutron stars are still largely unknown and are still subject of speculation.

 Scientists were able to detect gravitational waves of two merging Neutron stars and confirmed the theory of Albert Einstein.

French:

Étoile à neutrons

German:

Neutronenstern

Polish:

Gwiazda neutronowa

Swedish:

Neutronstjärna

Links to Videos/Articles:

https://www.youtube.com/watch?v=udFxKZRyQt4&list=PLFs4vir_WsTwEd-nJgVJCZPNL3HALHHpF&index=16

https://www.nasa.gov/mission_pages/GLAST/science/neutron_stars.html