Logo
Unionpedia
Communication
Get it on Google Play
New! Download Unionpedia on your Android™ device!
Install
Faster access than browser!
 

HD 157661

+ Save concept

HD 157661 is the Henry Draper Catalogue designation for a likely triple star in the southern constellation of Ara. [1]

15 relations: Angular distance, Apparent magnitude, Ara (constellation), B-type main-sequence star, Bright Star Catalogue, Constellation, Durchmusterung, Henry Draper Catalogue, Hipparcos, International Astronomical Union, Minute and second of arc, Monthly Notices of the Royal Astronomical Society, Parallax, Star system, Stellar classification.

Angular distance

In mathematics (in particular geometry and trigonometry) and all natural sciences (e.g. astronomy and geophysics), the angular distance (angular separation, apparent distance, or apparent separation) between two point objects, as viewed from a location different from either of these objects, is the angle of length between the two directions originating from the observer and pointing toward these two objects.

New!!: HD 157661 and Angular distance · See more »

Apparent magnitude

The apparent magnitude of a celestial object is a number that is a measure of its brightness as seen by an observer on Earth.

New!!: HD 157661 and Apparent magnitude · See more »

Ara (constellation)

Ara (Latin: "The Altar") is a southern constellation situated between Scorpius and Triangulum Australe.

New!!: HD 157661 and Ara (constellation) · See more »

B-type main-sequence star

A B-type main-sequence star (B V) is a main-sequence (hydrogen-burning) star of spectral type B and luminosity class V. These stars have from 2 to 16 times the mass of the Sun and surface temperatures between 10,000 and 30,000 K. B-type stars are extremely luminous and blue.

New!!: HD 157661 and B-type main-sequence star · See more »

Bright Star Catalogue

The Bright Star Catalogue, also known as the Yale Catalogue of Bright Stars or Yale Bright Star Catalogue, is a star catalogue that lists all stars of stellar magnitude 6.5 or brighter, which is roughly every star visible to the naked eye from Earth.

New!!: HD 157661 and Bright Star Catalogue · See more »

Christmas

Christmas is an annual festival commemorating the birth of Jesus Christ,Martindale, Cyril Charles.

New!!: HD 157661 and Christmas · See more »

Christmas and holiday season

The Christmas season, also called the festive season, or the holiday season (mainly in the U.S. and Canada; often simply called the holidays),, is an annually recurring period recognized in many Western and Western-influenced countries that is generally considered to run from late November to early January.

New!!: HD 157661 and Christmas and holiday season · See more »

Christmas Eve

Christmas Eve is the evening or entire day before Christmas Day, the festival commemorating the birth of Jesus.

New!!: HD 157661 and Christmas Eve · See more »

Christmas traditions

Christmas traditions vary from country to country.

New!!: HD 157661 and Christmas traditions · See more »

Constellation

A constellation is a group of stars that are considered to form imaginary outlines or meaningful patterns on the celestial sphere, typically representing animals, mythological people or gods, mythological creatures, or manufactured devices.

New!!: HD 157661 and Constellation · See more »

Durchmusterung

In astronomy, Durchmusterung or Bonner Durchmusterung (BD), is the comprehensive astrometric star catalogue of the whole sky, compiled by the Bonn Observatory (Germany) from 1859 to 1903.

New!!: HD 157661 and Durchmusterung · See more »

Henry Draper Catalogue

The Henry Draper Catalogue (HD) is an astronomical star catalogue published between 1918 and 1924, giving spectroscopic classifications for 225,300 stars; it was later expanded by the Henry Draper Extension (HDE), published between 1925 and 1936, which gave classifications for 46,850 more stars, and by the Henry Draper Extension Charts (HDEC), published from 1937 to 1949 in the form of charts, which gave classifications for 86,933 more stars.

New!!: HD 157661 and Henry Draper Catalogue · See more »

Hipparcos

Hipparcos was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993.

New!!: HD 157661 and Hipparcos · See more »

International Astronomical Union

The International Astronomical Union (IAU; Union astronomique internationale, UAI) is an international association of professional astronomers, at the PhD level and beyond, active in professional research and education in astronomy.

New!!: HD 157661 and International Astronomical Union · See more »

Minute and second of arc

A minute of arc, arcminute (arcmin), arc minute, or minute arc is a unit of angular measurement equal to of one degree.

New!!: HD 157661 and Minute and second of arc · See more »

Monthly Notices of the Royal Astronomical Society

Monthly Notices of the Royal Astronomical Society (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics.

New!!: HD 157661 and Monthly Notices of the Royal Astronomical Society · See more »

New Year

New Year is the time or day at which a new calendar year begins and the calendar's year count increments by one.

New!!: HD 157661 and New Year · See more »

New Year's Day

New Year's Day, also called simply New Year's or New Year, is observed on January 1, the first day of the year on the modern Gregorian calendar as well as the Julian calendar.

New!!: HD 157661 and New Year's Day · See more »

New Year's Eve

In the Gregorian calendar, New Year's Eve (also known as Old Year's Day or Saint Sylvester's Day in many countries), the last day of the year, is on 31 December which is the seventh day of Christmastide.

New!!: HD 157661 and New Year's Eve · See more »

Parallax

Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines.

New!!: HD 157661 and Parallax · See more »

Star system

A star system or stellar system is a small number of stars that orbit each other, bound by gravitational attraction.

New!!: HD 157661 and Star system · See more »

Stellar classification

In astronomy, stellar classification is the classification of stars based on their spectral characteristics.

New!!: HD 157661 and Stellar classification · See more »

2018

2018 has been designated as the third International Year of the Reef by the International Coral Reef Initiative.

New!!: HD 157661 and 2018 · See more »

2019

2019 (MMXIX) will be a common year starting on Tuesday of the Gregorian calendar, the 2019th year of the Common Era (CE) and Anno Domini (AD) designations, the 19th year of the 3rd millennium, the 19th year of the 21st century, and the 10th and last year of the 2010s decade.

New!!: HD 157661 and 2019 · See more »

Redirects here:

CCDM J17268-4550, H 4949, HIC 85389, HIP 85389, HJ 4949, HR 6477, IDS 17195-4545.

References

[1] https://en.wikipedia.org/wiki/HD_157661

OutgoingIncoming
Hey! We are on Facebook now! »