Definitions for h ii region
h ii region

WiktionaryRate this definition:0.0 / 0 votes

1. H II regionnoun

   A large nebula of gas and plasma of glowing low density in which star formation has recently taken place.

WikipediaRate this definition:0.0 / 0 votes

1. H II region

   An H II region or HII region is a region of interstellar atomic hydrogen that is ionized. It is typically in a molecular cloud of partially ionized gas in which star formation has recently taken place, with a size ranging from one to hundreds of light years, and density from a few to about a million particles per cubic centimetre. The Orion Nebula, now known to be an H II region, was observed in 1610 by Nicolas-Claude Fabri de Peiresc by telescope, the first such object discovered. The regions may be of any shape because the distribution of the stars and gas inside them is irregular. The short-lived blue stars created in these regions emit copious amounts of ultraviolet light that ionize the surrounding gas. H II regions—sometimes several hundred light-years across—are often associated with giant molecular clouds. They often appear clumpy and filamentary, sometimes showing intricate shapes such as the Horsehead Nebula. H II regions may give birth to thousands of stars over a period of several million years. In the end, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster disperse the gases of the H II region, leaving a cluster of stars which have formed. H II regions can be observed at considerable distances in the universe, and the study of extragalactic H II regions is important in determining the distances and chemical composition of galaxies. Spiral and irregular galaxies contain many H II regions, while elliptical galaxies are almost devoid of them. In spiral galaxies, including our Milky Way, H II regions are concentrated in the spiral arms, while in irregular galaxies they are distributed chaotically. Some galaxies contain huge H II regions, which may contain tens of thousands of stars. Examples include the 30 Doradus region in the Large Magellanic Cloud and NGC 604 in the Triangulum Galaxy.

WikidataRate this definition:0.0 / 0 votes

1. H II region

   An H II region is a large, low-density cloud of partially ionized gas in which star formation has recently taken place. The short-lived, blue stars forged in these regions emit copious amounts of ultraviolet light, that ionize the surrounding gas. H II regions—sometimes several hundred light-years across—are often associated with giant molecular clouds. The first known H II region was the Orion Nebula, which was discovered in 1610 by Nicolas-Claude Fabri de Peiresc. H II regions are named for the large amount of ionised atomic hydrogen they contain, referred to as H II, pronounced H-two by astronomers. Such regions have extremely diverse shapes, because the distribution of the stars and gas inside them is irregular. They often appear clumpy and filamentary, sometimes showing bizarre shapes such as the Horsehead Nebula. H II regions may give birth to thousands of stars over a period of several million years. In the end, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster will disperse the gases of the H II region, leaving behind a cluster of birthed stars such as the Pleiades.

How to pronounce h ii region?

1. Alex

   US English

   David

   US English

   Mark

   US English

   Daniel

   British

   Libby

   British

   Mia

   British

   Karen

   Australian

   Hayley

   Australian

   Natasha

   Australian

   Veena

   Indian

   Priya

   Indian

   Neerja

   Indian

   Zira

   US English

   Oliver

   British

   Wendy

   British

   Fred

   US English

   Tessa

   South African

How to say h ii region in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of h ii region in Chaldean Numerology is: 3

2. Pythagorean Numerology

   The numerical value of h ii region in Pythagorean Numerology is: 4

Examples of h ii region in a Sentence

1. Mike Pence:

   There's no question North Korea represents the most dangerous and most immediate threat in the Asia-Pacific and President Trump is determined to confront that threat by marshaling unprecedented cooperation with allies in the region and China and the world, that kind of economic and diplomatic pressure will result we hope in the regime in Pyongyang forfeiting their ambitions, forfeiting their nuclear weapons program and join the family of nations.

2. President Barack Obama:

   I don't think that there are a lot of folks in. the region who are disappointed that Assad is no longer in possession of one of the biggest stockpiles of chemical weapons of any country on earth, those have been eliminated.

3. Justine Walker:

   What we’re seeing now is a bit more about messaging to the region and indicating the seriousness of these sanctions.

4. State John Kerry on Tuesday:

   Completing the TPP would send a message throughout the region, as well as the world, that America is and will continue to be a leading force for prosperity and security in the Asia Pacific.

5. Ida Lauterbach:

   I decided that higher wages and better job prospects aren't as important as my home region, which is why I will return as soon as the possibility arises.

References

1. ^ Wiktionary
   https://en.wiktionary.org/wiki/H_Ii_Region
2. ^ Wikipedia
   https://en.wikipedia.org/wiki/H_Ii_Region
3. ^ Wikidata
   https://www.wikidata.org/w/index.php?search=h ii region