Science

NASA Satellites To Depart On Journey To Earth’s Upper Atmosphere

Thus far, information about the far reaches of Earth’s upper atmosphere has been limited. Ars Technica reports that the last time we really got a good look at Earth’s ionosphere was back in 1972 – and it’s time to collect data using modern equipment. Two NASA-sponsored satellites are headed into Earth’s upper atmosphere to obtain information on the data and temperature of this relatively unstudied area surrounding our planet.

Earth's upper atmosphere
Image source: YouTube Video Screenshot

Earth’s Upper Atmosphere

The Earth’s upper atmosphere, known as the ionosphere, is an area in near-earth space made up of charged particles. These particles coexist with neutral gases in the same area that are sometimes shaped due to weather events occuring in lower portion of the atmosphere.

As mentioned above, we have a surprising amount of gaps in our knowledge about Earth’s upper atmosphere, and the Global-Scale Observations of the Limb and Disk (GOLD) mission is scheduled to launch later this month in hopes to address this issue.

Sarah Jones, a scientist involved with the GOLD mission, spoke this week in a NASA briefing, stating that “[NASA would] really like to be able to tease out the effects form the Sun above and the Earth below…The ionosphere is a really dynamic place.”

Previous theories in the scientific community imagined that the Sun’s radiation was the main influence on the Earth’s upper atmosphere, but recent knowledge suggests that the weather on the planet’s surface may actually have a significant effect as well. The GOLD mission will attempt to confirm these thoughts while providing greater insight into the ionosphere as a whole.

GOLD Mission Satellites

The GOLD mission is actually carried out on incredibly small “microwave-sized” satellites, and those devices will be carried into Earth’s upper atmosphere by a much larger commercial satellite – the SES-14. This is the first time that NASA has included a satellite on an expedition launched from a private company, and was apparently decided on as a cost-saving measure. With these savings, the price of the journey to Earth’s upper atmosphere is capped at $55 million – a significant amount of money, but far less than it would cost if NASA were to launch the satellites on their own.

The GOLD satellites have already been delivered to Kourou, in French Guiana, for a launch scheduled on January 25th. It will take a few months for the payload to reach its target geostationary orbit at 35000 km above Earth, at which point it will have a wide view of Earth’s western hemisphere.

The GOLD satellite will then use an ultraviolet-imaging spectrograph to take images of Earth’s upper atmosphere and break the images down by wavelength. These wavelengths will give scientists valuable information about temperature, density, and composition at that point in time. The Earth’s upper atmosphere will be imaged every 30 minutes, which will also give us a good sense of how the ionosphere is changing.

In addition to expanding our academic knowledge, the GOLD mission will provide a practical understanding of how ions and electrons garble radio signals that move through the upper atmosphere from one part of the Earth to another. This new understanding will help us improve communication systems for several industries – most notably the military – which makes this journey to Earth’s upper atmosphere a worthwhile affair.