Himiko is a large gas cloud found at redshift of z=6.6 that predates similar

Lyman-alpha blob In astronomy, a Lyman-alpha blob (LAB) is a huge concentration of a gas emitting the Lyman-alpha emission line. LABs are some of the largest known individual objects in the Universe. Some of these gaseous structures are more than 400,000 light ...

s. At the time of its discovery in 2009, researchers said it "may represent the most massive object ever discovered in the early universe". It is located in

Cetus Cetus () is a constellation, sometimes called 'the whale' in English. The Cetus was a sea monster in Greek mythology which both Perseus and Heracles needed to slay. Cetus is in the region of the sky that contains other water-related constellat ...

at redshift z=6.595, about 12.9 billion

light years A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...

from Earth, or about miles ( kilometers).

Characteristics

This nebular gas cloud is thought to be a

protogalaxy In physical cosmology, a protogalaxy, which could also be called a "primeval galaxy", is a cloud of gas which is forming into a galaxy. It is believed that the rate of star formation during this period of galactic evolution will determine whethe ...

, caught in the act of formation. There have been no spectroscopic signatures of anything other than hydrogen or helium, and its luminance cannot be ascribed to gravitational lensing, black holes or exterior excitation. The lack of any chemical signatures other than hydrogen and helium illustrate the extreme primitiveness of the object, and early enough so as not to be polluted by carbon signatures from young stars.

Size

It is 55,000 light years across (half the diameter of our galaxy), and at the time of discovery, said to "hold more than 10 times as much mass as the next largest object found in the early universe, or roughly the equivalent mass of 40 billion Suns".

Discovery

Masami Ouchi, a researcher at the Carnegie Institution in Pasadena, California, stated "I have never heard about any imilarobjects that could be resolved at this distance... 's kind of record-breaking."

Name

The object was named by a Japanese scientist after the 3rd-century Japanese shaman queen

Himiko , also known as , was a shamaness-queen of Yamatai-koku in . Early Chinese dynastic histories chronicle tributary relations between Queen Himiko and the Cao Wei Kingdom (220–265) and record that the Yayoi period people chose her as ruler fol ...

References

External links