Renewed activity from GX 399-4

Further to the alert by Markwardt et al. (ATel #1945), the Swift-BAT scaled map transient analysis and the RXTE Galactic bulge scans indicate that GX 339-4 is entering another epoch of activity. Within the RXTE-PCA energy band the source has attained its brightest state since the 2007 major outburst. Monitoring over the coming weeks will reveal whether this source continues to brighten towards a major outburst or undergoes one of its more common minor high state episodes.