Observation of the X1.0 flare and the filament eruption. (a) Angular locations of the Sun, the flare site, and STEREO, with respect to the Earth. (b) GOES soft X-ray flux. (c)–(f) Observations of the filament motion during the eruption from SDO/AIA and STEREO-A/EUVI with wavelengths of 304 Å, 171 Å, 131 Å, and 195 Å, respectively. The first row displays a clear J-shaped filament that remains stable before the flare onset. The second row shows that the filament starts to rise up quickly. The third row presents the eruption of the filament and the flare ribbons. An animation of SDO/AIA observation with cadence of 1 min is attached.