Infrared Astronomy

JAXA Akari was a space-based infrared astronomical observatory launched by the Japan Aerospace Exploration Agency (JAXA) on February 21, 2006. The mission was designed to study the sky in the mid- to far-infrared wavelength range, which is not observable from the ground due to atmospheric absorption. In this article, we will discuss the details of the JAXA Akari mission, including its launching date, objectives, technical specifications, cost, and achievements.

Launching Date:

JAXA Akari was launched on February 21, 2006, from the Uchinoura Space Center in Japan. The observatory was launched aboard an M-V rocket, which is a three-stage solid-fuel rocket designed and built by JAXA. The launch was successful, and the observatory was placed into a sun-synchronous orbit at an altitude of approximately 700 kilometers above the Earth's surface.

Objectives:

The primary objective of the JAXA Akari mission was to conduct a comprehensive survey of the sky in the mid- to far-infrared wavelength range. This survey aimed to improve our understanding of the formation and evolution of stars and galaxies, as well as the structure and chemical composition of the interstellar medium. Additionally, the mission aimed to search for new classes of astronomical objects, such as brown dwarfs and dusty galaxies.

Technical Specifications:

JAXA Akari was equipped with a 68.5 cm diameter telescope, which was cooled to a temperature of approximately 6 Kelvin using a liquid helium cooling system. The observatory carried two scientific instruments: the Far-Infrared Surveyor (FIS) and the Infrared Camera (IRC). The FIS covered a wavelength range of 50 to 180 micrometers, while the IRC covered a range of 2.4 to 26 micrometers. The observatory had a field of view of approximately 10 arcminutes for the FIS and 10x10 arcminutes for the IRC.

Cost:

The total cost of the JAXA Akari mission was approximately 14.5 billion yen (approximately $130 million USD). This includes the cost of the observatory, launch vehicle, and mission operations.

Achievements:

The JAXA Akari mission was highly successful, and its achievements include:

Comprehensive survey of the sky: JAXA Akari conducted the first comprehensive survey of the entire sky in the mid- to far-infrared wavelength range. The survey produced a catalog of over 1,000,000 sources, which is a significant increase from the previous surveys conducted by the Infrared Astronomical Satellite (IRAS) in 1983.

Discovery of new classes of astronomical objects: JAXA Akari discovered several new classes of astronomical objects, including ultra-luminous infrared galaxies, hot debris disks, and faint dusty galaxies.

Improved understanding of star formation: JAXA Akari's observations of star-forming regions provided new insights into the physical processes involved in star formation. The observatory observed the earliest stages of star formation, including the formation of protostars and the evolution of protoplanetary disks.

Mapping of the interstellar medium: JAXA Akari's observations of the interstellar medium provided detailed maps of the distribution of dust and gas in our galaxy. These maps have provided important insights into the structure and chemical composition of the interstellar medium.

Legacy for future missions: JAXA Akari's comprehensive survey of the sky and its discovery of new classes of astronomical objects have provided a valuable legacy for future missions in the field of infrared astronomy.

In conclusion, the JAXA Akari mission was a highly successful space-based infrared astronomical observatory launched by the Japan Aerospace Exploration Agency (JAXA) in 2006. The mission was designed to survey the sky in the mid- to far-infrared wavelength range, which is not observable from the ground due to atmospheric absorption. JAXA Akari's observations have significantly advanced our understanding of the formation and evolution of stars and galaxies, as well as the structure and chemical composition of the interstellar medium. The observatory's achievements, including the discovery of new classes of astronomical objects and the mapping of the interstellar medium, have provided a valuable legacy for future missions in the field of infrared astronomy. JAXA Akari operated for five years, during which it completed its primary mission objectives and contributed significantly to the advancement of infrared astronomy. In November 2011, JAXA officially terminated the mission due to the depletion of its liquid helium coolant. However, the observatory's legacy continues to influence and inspire current and future generations of scientists in the field of astronomy.