  Monitor of All-sky X-ray Image (MAXI) is mounted on the International Space
Station (ISS). Since 2009 it has been scanning the whole sky in every 92
minutes with ISS rotation. Due to high particle background at high latitude
regions the carbon anodes of three GSC cameras were broken. We limit the GSC
operation to low-latitude region around equator. GSC is suffering a double high
background from Gamma-ray altimeter of Soyuz spacecraft. MAXI issued the
37-month catalog with 500 sources above ~0.6 mCrab in 4-10 keV. MAXI issued 133
to Astronomers Telegram and 44 to Gammaray burst Coordinated Network so far.
One GSC camera had a small gas leak by a micrometeorite. Since 2013 June, the
1.4 atm Xe pressure went down to 0.6 atm in 2014 May 23. By gradually reducing
the high voltage we keep using the proportional counter. SSC with X-ray CCD has
detected diffuse soft X-rays in the all-sky, such as Cygnus super bubble and
north polar spur, as well as it found a fast soft X-ray nova MAXI J0158-744.
Although we operate CCD with charge-injection, the energy resolution is
degrading. In the 4.5 years of operation MAXI discovered 6 of 12 new black
holes. The long-term behaviors of these sources can be classified into two
types of the outbursts, 3 Fast Rise Exponential Decay (FRED) and 3 Fast Rise
and Flat Top (FRFT). The cause of types is still unknown.
