There were few follow-up studies for decades. Then the 1995 launch of the
Solar and Heliospheric Observatory (SOHO) led to observation of coronal waves, which cause Moreton waves. Moreton waves were a research topic again. (SOHO's
EIT instrument discovered another, different wave type called "EIT waves".)[5] The reality of Moreton waves (also known as fast-mode
MHD waves) has also been confirmed by the two
Solar Terrestrial Relations Observatory (STEREO) spacecraft. They observed a 100,000-km-high wave of hot plasma and magnetism, moving at 250 km/s, in conjunction with a big
coronal mass ejection in February 2009.[6][7]
Moreton measured the waves propagating at a
speed of 500–1500 km/s.[6] Yutaka Uchida interpreted Moreton waves as MHD fast mode shock waves propagating in the corona.[8] He links them to type II radio bursts, which are radio-wave discharges created when coronal mass ejections accelerate shocks.[9]
Moreton waves can be observed primarily in the
Hα band.[10]
^Sakurai, Takashi (3 September 2002).
"SolarNews Newsletter". Solar Physics Division, American Astronomical Society. Archived from
the original on 27 August 2011. Retrieved 15 June 2011.