NASA has announced that it is going forward with its Ionospheric Connection Explorer (ICON). Scheduled to launch in 2017, the orbital mission aims to study the effects of the lower atmosphere on the ionosphere and its impact on the Earth’s surface.
Starting 85 km (53 mi) up and ranging out to 600 km (370 mi), the ionosphere might seem more like a resident of a crossword puzzle than a factor in everyday life to most of us, but disturbances in it can have huge effects on communication, GPS navigation, and many other technologies that rely on radio. The region is a near-vacuum on the edge of space where the tenuous atmosphere is ionized by solar radiation. The charged atoms that make it up act as a reflector that allows shortwave transmissions to bounce over the horizon, as well as a barrier that satellite broadcasts must punch through. However the nature of the ionosphere is far from stable and a major concern for researchers in space weather is to find ways of predicting the ionosphere’s behavior.
Until recently, it was thought that the only real factors affecting the ionosphere are the Sun and the Earth’s magnetic field. But NASA says that recent observations show that the movements of the lower layers of the atmosphere have a strong effect as well. According to the space agency, ultraviolet images show bright areas in the ionosphere that correspond to daily cycles and seasons in the lower altitudes that could indicate a link between activity in the ionosphere and common weather events.
To better understand the ionosphere, ICON will be set in a 360 mi (580 km) high orbit, where it can maintain observations of the edge of space (62 mi/100 km), and up to 250 mi (400 km). The hope is that by gathering enough data, it will one day be possible to predict disturbances in the upper regions as easily as terrestrial weather is forecast.
ICON’s suite of four instruments include the Michelson Interferometer for Global High-Resolution Thermospheric Imaging (MIGHTI) for measuring the speed and temperature of neutrally charged particles in the Earth’s atmosphere, a Ion Velocity Meter for measuring the speed of charged particles, and a pair of spectroscopes operating in the extreme and far ultraviolet spectra for identifying to composition of charged and neutral particles.
NASA says that ICON’s critical design review is scheduled for 2015 with the launch date set at before October 2017.
Source: NASA
