We present an update on the results of our monitoring observations of the X-ray remnant of supernova ( SN ) 1987A with the Chandra X-Ray Observatory .
As of 2002 December , we have performed a total of seven observations of SN 1987A , which allows us to monitor the details of the earliest stage of the supernova remnant evolution in X-rays .
The high angular resolution images from the latest data reveal developments of new X-ray bright spots in the northwestern and the southwestern portions of the remnant as well as changes on the eastern side .
The observed soft X-ray flux is increasing more rapidly than ever , and the latest 0.5 - 2 keV band flux ( f _ { X } \sim 6 \times 10 ^ { -13 } ergs cm ^ { -2 } s ^ { -1 } ) is four times brighter than three years earlier when this monitoring began .
The overall X-ray emission is primarily from the blast wave shock with kT \sim 2.4 keV .
As the blast wave approaches the dense circumstellar material , the contribution from the decelerated slow shock ( kT \sim 
0.22 keV ) to the observed X-ray emission is becoming significant .
The increase of this slow shock contribution over the last two years is particularly noticeable in the western half of the remnant .
These results indicate that the shock front is now reaching the main body of the inner circumstellar ring and that SN 1987A will be a complete ring with dramatic brightening in coming years .
Based on the best-fit two-shock spectral model , we derive approximate densities of the X-ray-emitting regions ( n _ { e } \sim 235 cm ^ { -3 } for the fast shock and n _ { e } \sim 7500 cm ^ { -3 } for the slow shock ) .
There is no direct observational evidence to date for a neutron star associated with supernova remnant 1987A .
We obtain an upper limit on the observed X-ray luminosity of any embedded point source ( L _ { X } \leq 1.5 \times 10 ^ { 34 } ergs s ^ { -1 } ) in the 2 - 10 keV band .
The X-ray remnant continues to expand linearly at a rate of 4167 km s ^ { -1 } .