Monitor of All-Sky X-Ray Image (MAXI)
Research Area: Astrophysics
Expedition(s): 19-ongoing
Principal Investigator(s): ● Masaru Matsuoka, PhD, Institute of Physical and Chemical
Research, Saitama, Japan
RESEARCH OBJECTIVES
Monitor of All-Sky X-Ray Image (MAXI) is an all-sky X-ray monitor located on the Japanese
Experimental Module’s Exposed Facility of the International Space Station (ISS). MAXI looks for
galactic transient phenomena in the X-ray spectrum of the sky. When interesting phenomena
are discovered, the
information is made
available to astronomers
around the world.
EARTH BENEFIT
The all-sky X-ray pictures
obtained with MAXI are very
useful in furthering science
education. Images have
already appeared in a
planetarium program, a
Japanese physics textbook,
and a United States
astronomy textbook.
SPACE BENEFIT
The X-ray charge-coupled device (CCD) camera technology developed for MAXI was used on the
Hayabusa spacecraft that returned samples from a near Earth asteroid in 2010.
RESULTS
BLACK HOLE CANDIDATES
MAXI has a distinctive capability of monitoring the outbursts of black hole binaries from
beginning to end. MAXI is particularly useful in discovering and monitoring the very early phase
of outbursts. MAXI discovered 5 new black hole candidates, named MAXI J1659− 152 (Negoro
2010), MAXI J1543−564 (Negoro 2011a), MAXI J1836−194 (Negoro 2011b), MAXI J1305− 704
(Sato 2012), and MAXI J1910−057 (Usui 2012). Since the activation of MAXI, half of all new
black hole candidates have been discovered by MAXI.
All-sky image with Monitor of All-sky X-ray Image (MAXI) Gas Slit Camera
(GSC). The 1.5 year data was used. The black hole candidates detected with
MAXI are shown with the names. JAXA image.