The Rosetta spacecraft has just witnessed a dramatic comet outburst.
The European Space Agency (ESA) has recently released images captured by the Rosetta probe showing a bright burst of light coming from the comet 67P/Churyumov-Gerasimenko. According to scientists, the eruption may have been caused by a landslide. In these images, ESA shows the eruption in half-hour intervals while the comet rotates.
"Over the last year, Rosetta has shown that although activity can be prolonged, when it comes to outbursts, the timing is highly unpredictable, so catching an event like this was pure luck," Matt Taylor, ESA's Rosetta project scientist, said in a news release.
"By happy coincidence, we were pointing the majority of instruments at the comet at this time, and having these simultaneous measurements provides us with the most complete set of data on an outburst ever collected."
Rosetta's OSIRIS wide-angled camera captured the outburst, which happened in Feb. 19 in the Atum region of the comet when the spacecraft had been 35 kilometers from the comet. Rosetta's instruments, including its cameras, dust collectors, and gas and plasma analyzers, had been observing the comet. The probe had detected an increase in ultraviolet light reflected by the comet, dust, plasma and gas, as well as a 30-degree rise in temperature of the surrounding gas.
A detailed analysis of the phenomenon is described in a paper authored by Eberhard Grün of the Max-Planck Institute for Nuclear Physics in Heidelberg, which will be published in the journal Monthly Notices of the Royal Astronomical Society.
"From Rosetta's observations, we believe the outburst originated from a steep slope on the comet's large lobe, in the Atum region," Grün said in a statement.
According to Grün, the outburst may have been triggered by a landslide. The outburst began when the area emerged from the shadow, which suggests that thermal stresses in the surface material caused a landslide that exposed fresh water ice to direct solar illumination. The ice immediately turned to gas, pulling the dust around to form a cloud of debris as seen by OSIRIS.
In November 2014, Rosetta launched on a mission to dispatch the Philae lander on the comet surface. However, the agency lost contact with Philae and shut down its communications link with the lander.
Rosetta is being prepared for a controlled landing on the comet as it moves into the outer solar system. On Sept. 30, ESA will crash the spacecraft into the comet's surface to capture close-up photographs and data from the comet, officially ending the mission.