36,351
edits
Eridanus: Difference between revisions
no edit summary
(Created page with "Eridanus is a constellation. It is represented as a river; its name is the Latin name for the Po River. It was one of the 48 constellations listed by the 2nd century astronome...") |
No edit summary |
||
| Line 1: | Line 1: | ||
Eridanus is a constellation. It is represented as a river; its name is the Latin name for the Po River. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations. It is the sixth largest of the modern constellations | Eridanus is a constellation. It is represented as a river; its name is the Latin name for the Po River. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations. It is the sixth largest of the modern constellations | ||
At its southern end is the magnitude 0.5 star Achernar, designated Alpha Eridani. 144 light-years from Earth, it is a blue-white hued main sequence star whose traditional name means "the river's end".Achernar is a very peculiar star because it is one of the flattest stars known. | |||
There are several other noteworthy stars in Eridanus, including some double stars. Beta Eridani, traditionally called Cursa, is a blue-white star of magnitude 2.8, 89 light-years from Earth. Its place to the south of Orion's foot gives it its name, which means "the footstool". Theta Eridani, called Acamar, is a binary star with blue-white components, distinguishable in small amateur telescopes and 161 light-years from Earth. The primary is of magnitude 3.2 and the secondary is of magnitude 4.3. 32 Eridani is a binary star 290 light-years from Earth. | |||
Epsilon Eridani is a star with one extrasolar planet similar to Jupiter. It is an orange-hued main-sequence star of magnitude 3.7, 10.5 light-years from Earth. Its one planet, with an approximate mass of one Jupiter mass, has a period of 7 years. | |||
The name Eridanus refers to the Po River, the main river of northern Italy. Its association with a river comes from the way its stars trace a tortuous path. In some star maps, Eridanus is depicted as a river flowing from the waters poured by [[Aquarius]]. In such maps, Aquarius is visualized as facing Eridanus, requiring a different perspective and a redesign of how the stars of Aquarius connect, so the water pours onto the same side as Eridanus. | |||
==Supervoid== | ==Supervoid== | ||
The Eridanus Supervoid is a large supervoid (an area of the universe devoid ofgalaxies) discovered as of 2007. At a diameter of about one billion light years it is the second largest known void, superseded only by the Giant Void in Canes Venatici. It was discovered by linking a "cold spot" in the cosmic microwave background to an absence of radio galaxies in data of the United States National Radio Astronomy Observatory's Very Large Array Sky Survey.There is some speculation that the void may be due to quantum entanglementbetween our universe and another. | The Eridanus Supervoid is a large supervoid (an area of the universe devoid ofgalaxies) discovered as of 2007. At a diameter of about one billion light years it is the second largest known void, superseded only by the Giant Void in Canes Venatici. It was discovered by linking a "cold spot" in the cosmic microwave background to an absence of radio galaxies in data of the United States National Radio Astronomy Observatory's Very Large Array Sky Survey.There is some speculation that the void may be due to quantum entanglementbetween our universe and another. | ||