Look up. Do you see a satellite? Probably not, but it might be looking at you. Alternatively, it could be looking out into the universe.
With the number of satellites whizzing over our heads increasing at an astonishing rate, Cosmos looks back at our favourite five satellites this year.
Here’s looking at you, kid
The question of who owns the space above our heads has been a scorching and contentious topic this year.
Clusters of satellites, known as constellations (a slightly ironic term, given their potential to ultimately block the pictures in the skies our ancestors have traced for millennia) – will provide valuable communications essential for our digital evolution… or clutter up the sky – depending on your viewpoint.
September this year saw the launch of AST SpaceMobile’s Bluewalker 3 on SpaceX’s Falcon 9 rocket, the largest commercial communications satellite in low-Earth orbit. The giant solar panels were unfurled a few months later and reports of sightings poured in from amateur and professional astronomers alike.
This is an interesting space to watch as various commercial, research and public interests are negotiated.
Slow-mo space crash
Like watching a braking train slam into a hapless car stuck on the tracks, millions of people tuned in to see the impact of the Double Asteroid Redirection Test (DART) spacecraft on the innocently waiting asteroid moonlet, tiny Dimorphos.
Agenzia Spaziale Italiana’s LICIACube (Light Italian CubeSat for Imaging Asteroids), a small cubesat armed with twin cameras, ‘LUKE’ (LICIACube Unit Key Explorer) and ‘LEIA’ (LICIACube Explorer Imaging for Asteroid) was there to record the gory impact in incredible detail.
Weather satellite captures more than expected
Over the past few years, Betelgeuse, the iconic red supergiant, caused a flurry of excitement amongst astronomers who originally thought perhaps its dimming could be an indication of an impending supernova.
Infrared and optical observations from Himawari-8 – a weather satellite operated by the Japan Meteorological Agency – proved to be ideal for probing Betelgeuse’s dimming, with researchers discovering that a large dust cloud hanging around the star was likely partly responsible for the phenomenon.
Hunting from space
NASA’s Orbiting Carbon Observatory 2 (OCO-2) and OCO-3 (the latter of which is attached to the International Space Station) are two satellites demonstrating the potential of satellites to help hold polluters accountable.
The satellites monitor carbon emissions from space in real time and the data can then be matched to those reported by emitters – such as power plants.
Although there are still challenges – being unable to see emissions through cloud cover or when plumes pass over water bodies or mountains, for instance – expect to see the next generation of monitoring satellites helping guide climate policy decisions.
Faster flood data
Many parts of Australia have experienced devastating flooding over the past few years and key to a good response is the ability to accurately monitor and model the often-unpredictable behaviour of rising waters.
An Australian team has combined radar and optical imaging from a number of Earth-observation satellites such as Capella (radar), Planet Inc. and NASA’s VIIRS (both optical), developing a better way to map flooding even through atmospheric interference such as smoke, clouds and storms.
This novel approach could help authorities characterise risk, more rapidly warn communities and assess damage and direct response post-flood event.