Alberta satellite poised for orbit
Device will head to thermosphere to provide data on weather
With T-minus 41/2 months before the first Alberta-made satellite will be launched into space, members of the University of Alberta’s AlbertaSat team say they are ready for takeoff.
“It’s very exciting,” said Charles Nokes, project manager for the AlbertaSat team. “It’s been the culmination of 31/2 years of work, so it’s very exciting to see that come to fruition and actually get into space.”
Students at the University of Alberta have been working on a CubeSat — a satellite standard developed in 1999 for low-cost, cube-shaped satellites measuring 10 centimetres on a side — which will be launched into orbit with 50 other CubeSats as part of the QB50 mission. Each satellite is equipped with one of three sensors that will be dispersed through the Earth’s lower thermosphere to measure how it is affected by space weather events.
The thermosphere is a layer of Earth’s atmosphere above the stratosphere and mesosphere, between 90 kilometres and 700 kilometres above the surface of the Earth, filled with atoms and molecules that absorb large amounts of radiation from the sun.
Space weather events, such as solar flares, can cause a spike in the density of electrons in the thermosphere.
“The lower thermosphere kind of breathes, it expands and contracts, so by having 50 satellites working together taking measurements all around the Earth at the same time, researchers will be better able to understand and visualize what that looks like,” said Nokes.
According to Jan Thoemel, project manager of the QB50 mission, these fluctuations in the density of electrons in the thermosphere can interfere with satellite signals and even change the trajectory of satellites in orbit.
An example of the impact of these large space weather events on Earth was the March 13, 1989, geomagnetic storm that wiped out a large part of Hydro-Quebec’s power grid, leaving the province without power for nine hours.
While Thoemel said large weather events like that are rare, moderate storms can disrupt satellite signals, interfering with GPS and other systems used to monitor aircraft or satellites. Coupled with a lack of understanding of how the density of Earth’s thermosphere changes the trajectory of a satellite in orbit, in the event connection is lost with satellites during one of these solar events, Thoemel said there is a risk of catastrophic satellite collisions that could put even the International Space Station at risk.
“In our world, we depend more and more on the electronic means of these devices, and our dependency on these will only increase. Therefore, it is important that we understand the thermosphere,” Thoemel said.
Unfortunately, the density of electrons in the thermosphere cannot be measured from the surface of the Earth, and until this point scientists have had to rely on limited data taken from single points in the thermosphere at one time.
“What we can do (with the QB50 mission) is a multi-point measurement with these many satellites (and) many sensors. That has not been achieved before. Here we will be doing an unprecedented scientific campaign,” Thoemel said.
AlbertaSat’s satellite, the ExAlta 1, will also be equipped with a digital fluxgate magnetometer designed at the University of Alberta, which will measure how solar winds interact with Earth’s magnetic field.
Nokes said the Ex-Alta 1 has made it through the final tests and the AlbertaSat team is eagerly awaiting the QB50 mission launch on Dec. 13.
Should the launch go as planned, almost all of the 50 satellites — with a few being held for second launch that are set to go into a polar orbit — will arrive at the International Space Station, where astronauts will set the satellites adrift in the thermosphere.
The satellites will then send measurements from multiple points in the thermosphere back to researchers on Earth for anywhere between nine and 14 months before the satellites burn up in the atmosphere.
What we can do is a multipoint measurement with these many satellites ... That has not been achieved before. Here we will be doing an unprecedented scientific campaign.