Right Ascension

The stars on the celestial sphere are like places on the globe.These Places can be located on the globe using latitude and longitude. Longitude says how far the place is east or west along the Earth’s equator; latitude says how far a place is north or south of the Earth’s equator.

Right ascension (RA) is like longitude. It locates where a star is along the celestial equator. The zero point of longitude has been chosen to be where the line straight down from the Greenwich Observatory in England meets the equator. The zero point for right ascension is the vernal equinox. To find the right ascension of a star follow an hour circle “straight down” from the star to the celestial equator. The angle from the vernal equinox eastward to the foot of that hour circle is the star’s right ascension.

There is one oddity in right ascension: the unit used to report the angle. Right ascensions are always recorded in terms of hours, minutes, and seconds. One hour of right ascension (1h) is 15°. Since 24×15°=360°, there are 24h of right ascension around the celestial equator. The reason for this oddity is that the celestial sphere makes one full rotation (24h of RA) in one day (24 hours of time). Thus the celestial sphere advances about 1h of RA in an hour of time.




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Legacy and Meaning

Orlando Espinosa

The positive influence we have on others gives life some kind of legacy and meaning. Build something that outlives you!

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CFP – TICYUrb June 2018


Call for Papers and Posters:

The TICYUrb (Third International Conference of Young Urban Researchers) is an international event that aims to echo frontier research, artistic works and professional practice related to different urban contexts around the world, under an environment of vibrant dialog between academia and society.
The conference is split in ten tracks: Collectivecity (the right to the city: 50 years later), Productcity (the city as a product), Divercity (diversity in the city), Fractalcity (the city amid policies), Ucity (utopias and dystopias), Fearcity (in-security), Metacity (ways of thinking and making city), Transitcity (migrations and racism), RiskCity (risks in the city) and City O’clock (24 hours in the city). We encourage the submission of theoretical and empirical works about these topics. TICYUrb wish to act as a bridge between social, human, natural and all other scientific domains, so every paper will be welcomed and accepted for consideration.
We encourage the…

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Hurricane Maria threatens Puerto Rico, other Caribbean islands

Dear Kitty. Some blog

This music video says about itself:

West Side Story – Maria (Carreras)

19 December 2012


Tony: Josep Carreras

Conductor: Leonard Bernstein
Music: Leonard Bernstein
Lyrics: Stephen Sondheim

Maria is a very widespread women’s name; with variations in some languages like Mary in English and Mariam in Arabic.

In the song Maria in the musical West Side Story, it stands for a lovely Puerto Rican girl whom the character Tony falls in love with.

The Maria we read about these days has also to do with Puerto Rico, but is far from lovely.

From the Rolling Harbour Abaco blog about the Bahamas:


September 19, 2017

In the life of a massive Cat. 5 hurricane, a lot can happen over 24 hours. One source reports ‘mind-boggling devastation’ on Dominica. Other islands on the storm’s path are braced for their…

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