MAXI News are updated every other week. Please visit News tab.

 The top image is "MAXI 10-year all-sky X-ray image" obtained with the Gas Slit Camera (GSC) (10 years) and Solid-state Slit Camera (SSC) (2 years) in 2009-2020. The colors indicate X-ray energy bands : soft (0.7-1 keV [SSC] + 2-4 keV[GSC] ) in red, middle (4-8 keV) in green, and hard (8-16 keV) in blue.  Roughly  1000 sources as well as the galactic ridge emission and faint diffuse structures are detected (visit 3MAXI catalog in Publication tab). Red sources are mostly supernova remnants. Orange sources are low-mass X-ray binaries and cluster of galaxies, and bule ones are mostly binary X-ray pulsars and AGNs. Both 1650V and 1550V data are used. Thanks to the deeper exposure fainter extra-galactic objects have become recognized.

The 4hour update was upgraded to the 3hour update ver7Lrkn 3h (2023.7.6)
The daily light curve of ver7L was updated to ver7.7L (2022.12.15)
MAXI stopped at 2025 Oct 12 23:01 UT due to a hardware problem. MAXI resumed observation at 2025 Oct 17 6:26 UT.
MAXI shut down suddenly at 2022 June 21 6:07 UT. It is the same phenomenon as in June 3. MAXI restarted on June 23 6:45 UT.
Data processor hang up on 2022 June 3 5:05 UT. MAXI restarted on June 7 4:43UT.
There was no data between 2022 January 8 00:43 UT and January 13, 3:50 UT due to a JEM trouble.
We recovered from the bad data problem of 2019 December - 2020 January. (2020.Feb.1.)

The 4-hour update ver6Lrkn was replaced by ver7Lrkn (2020.6.19)

The daily ver3 data was replaced by ver6L (2019.7.1), and by ver7L (2020.5.14)

MAXI Process version 3rkn was replaced by 6Lrkn. This version is updated every 4 hours and properly handles the gas-leaking camera (A-camera 0). It raises the efficiency for northern sources which A-camera 0 sometiems observe. (2019.5.20)

MAXI Process version 6m is open. This version properly handles the degraded cameras (A-camera 3 and B-camera0) and gas-leaking camera (A-camera 0). It raises the efficiency for northern sources which A/B-camera 0 and A-camera 3 sometiems observe. (2019.5.20)

MAXI obsevation was stopped from 2019 October 18 4:50 UT to 21 7:00 due to ISS power reduction operation.

MAXI discovery paper of MAXI J1535-571 (2018.9.20)

-->jump to Nakahira et al. PASJ 70 (2018).
-->jump to JAXA/ISS page (Japanese).

On September 2, 2017 the bright X-ray nova MAXI J1535-571 appeared.
Visit MAXI XXXX monitor tab in the left column.
On March 11, 2018 the bright X-ray nova MAXI J1820+070 appeared.
On January 26, 2019 the bright X-ray nova MAXI J1348-630 appeared.
Also visit MAXI-BAT hardness ratio page .

MAXI による中性子星合体からのX線放射の観測
 MAXI observations of X-ray counterpart of the first neutron star merger GW170817

Notice of erratum:
In the archived MAXI/GSC light-curve data, version 1.4, which had been released since 2012 November to 2013 April 24, the errors on the flux had been incorrectly stored. (They were the halves of those suppoed to be.) The erratum was fixed on 2013 April 26. If you have these light curve data, please download the latest one from our archive page, again.  
We apologize for causing the inconvenience.
(2013, April 24)

The same erratum as the above had been revived since 2013 July 22 to 2013 December 20.
We fixed the bug on 2013 December 21. If you have downloaded the light curve data, please update it on our archive site, again.
We apologize for the inconvenience. 
(2013 December 21)

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