2019: SPACE MISSIONS
Will Gater looks at the space missions and scientific endeavors that will dominate the coming year in astronomy
There are plenty of exciting missions, launches and encounters planned for the next 12 months – learn all about them here.
Ayear might be a fleeting moment in cosmic terms, but 2018 had it all when it came to astronomical advances, dramatic space launches and awe-inspiring revelations about the Universe. There was the spectacular first flight of SpaceX’s Falcon Heavy rocket, captivating results from the Gaia satellite, daring asteroid landings and the beginnings of an array of new space missions destined to study everything from Mercury to the Sun and even far-off alien worlds.
If you thought this exhilarating pace was going to slacken off in 2019, you’re very much mistaken. In fact, as the UK wakes up bleary-eyed on New Year’s Day, out in the distant reaches of the Solar System one of the year’s most anticipated events will be well underway: on 1 January NASA’s New Horizons probe will make a historic flyby of one of the numerous frozen objects in the Kuiper Belt, a vast swathe of icy bodies scattered across space beyond the planet Neptune. The object – officially catalogued as ‘2014 MU69’ but nicknamed ‘Ultima Thule’ by the NASA team – will be the farthest body that a man-made object has ever visited and promises to offer a window into the early Solar System and the conditions that formed the planets we know today.
Much of the excitement from this flyby comes from the unknown; and if New Horizons’ swoop past Pluto in >
July 2015 is anything to go by, there should be some thrilling moments when data and images from the probe reach Earth. For example, it’s not known for certain what shape Ultima Thule is – there’s a chance it could even be a binary object comprising two separate bodies. Then there’s the surface itself, which New Horizon’s cameras will image at highresolution; the spacecraft’s instruments should tell us what it’s made of, something that could hold important clues for understanding the history of our planetary neighbourhood.
While the Kuiper Belt might seem far distant from Earth, it’s right on our doorstep compared to some of the objects studied by the LIGO (Laser Interferometer Gravitational-Wave Observatory) and Virgo interferometers in the US and Europe. Gravitational waves are ripples in the fabric of space-time that can be produced by, among other things, cataclysmic phenomena such as the merging of neutron stars or black hole pairs. These cosmic ripples can travel immense distances across the Universe and their study is one of the most rapidly developing areas of astronomical research. In 2017 the field took a major leap forward when scientists detected gravitational waves from an 130 million year-old event – two neutron stars fusing – and so had enough time to alert astronomers, who then observed the event visually.
Professional astronomers had been alerted to look for the new glowing object by a private notification sent out by the researchers who had initially detected the gravitational ripples from the event. In 2019 the LIGO-Virgo teams will be making these alerts public so that astronomers everywhere – including dedicated amateurs with suitable optical and imaging equipment – can help make follow-up searches and observations of light sources associated with these enigmatic gravitational phenomena. If you’d like to find out more about the LIGO-Virgo ‘Open Public Alerts’ visit the LIGO webpage at www.ligo.org/ scientists/GWEMalerts.php.
Private enterprise takes off
Closer to home there’s one area of space exploration that’s set to see a great deal of activity in 2019 and that’s the work of various private companies developing vehicles capable of transporting astronauts into orbit. In particular, two firms – SpaceX and Boeing – have constructed spacecraft designed to ferry astronauts to the International Space Station from Florida, under the auspices of NASA’s Commercial Crew Program. SpaceX’s Crew Dragon capsule is scheduled to undergo its first test
flight – without astronauts inside – on a Falcon 9 rocket in January. That’ll be followed by a crewed launch, which is scheduled for sometime in June.
Similarly, Boeing has an uncrewed test of its Starliner spacecraft scheduled for March and another flight, with astronauts on board, pencilled in for August. All eyes will be on these tests as many in the US are hoping they will herald the moment when the country regains its ability to regularly launch astronauts from home turf – something it hasn’t been able to do for nearly eight years, following the retirement of the Space Shuttle.
One destination future commercial space missions may go to is our nearest neighbour, the Moon. In 2019 both the Chinese and Indian space agencies intend to send robotic missions to the Moon. In fact, at the time of writing the Chinese also have a lunar lander – Chang’e 4 – preparing for a launch in December 2018. The mission intends to touch down on the lunar far side, making it the first spacecraft to do so, and it will explore the South Pole-Aitken basin area with a 1.5m-long rover.
That mission will be followed in 2019 by Chang’e 5, which will send a sample-return probe to the lunar surface near Mons Rümker in the northwest of the nearside. Meanwhile the Indian Space Research Organisation (ISRO) is set to launch its Chandrayaan-2 lunar mission at the beginning of the year; it consists of a lander and rover as well as an orbiting lunar satellite. As with China’s Chang’e-4, the destination for the Chandrayaan-2 lander will be the Moon’s southern polar region.
Beyond the Moon, the asteroid belt will be another region of focus for robotic explorers in 2019. Both NASA and the Japanese Space Agency, JAXA, have spacecraft exploring asteroids this year. JAXA’s Hayabusa2 mission has already reached its target, a 900m-wide asteroid named ‘Ryugu’. In autumn
2018 it deployed several hopping probes to the surface of the asteroid including two ‘MINERVA-II-1’ landers, developed by JAXA and the University of Aizu, and the box-shaped MASCOT lander, built by CNES in France and DLR in Germany.
All of the landers were successful and returned extraordinary images showing fine details in the rocks that litter the surface landscape. The main Hayabusa2 spacecraft has been returning spectacular images of Ryugu of its own and in 2019 will jettison an ‘impactor’ toward the asteroid’s surface. The spacecraft will then approach the crater formed by the impactor and attempt to collect a sample of exposed subsurface material. If all goes to plan, it’s hoped Hayabusa2 will deliver the precious cargo to Earth in late 2020.
NASA’s OSIRIS-REx mission also has a sample-return capability and at the time of writing it is nearing arrival at its destination, the asteroid Bennu; 2019 will see the probe perform detailed photography and mapping of the shape and surface of Bennu ahead of its own sample collecting attempt, which is currently expected to occur in July of 2020.
Astronomers won’t just have their attention on our own planetary neighbourhood during 2019, though. NASA’s Transiting Exoplanet Survey Satellite (TESS) – which launched in April 2018 – will be scanning the skies looking for planets in other solar systems, orbiting in front of their parent stars; when these exoplanets do this they cause their star’s light to momentarily dim and it’s these small dips that TESS’s sensitive cameras will be on the look out for. TESS has already discovered its first extrasolar worlds using this method: a mini-Neptune-like planet orbiting a star 60 lightyears away and a scorched ‘hot Earth’ that rapidly circles a dwarf star 49 lightyears from us. And with the satellite set to survey 200,000 stars in its mission lifetime, it’s a pretty safe bet that 2019 will see it uncover even more.
In a similar vein, ESA is expected to launch its CHEOPS (CHaracterising ExOPlanets Satellite) mission sometime this year. Like TESS it will make studies of exoplanets that ‘transit’ in front of their stars. By making accurate measurements of the sizes of these distant worlds with CHEOPS, astronomers hope to learn more about their fundamental properties and how they formed and evolved.
So, among the many exciting moments we have to look forward to in space this year, 2019 could very well end with us not only having found an array of new alien worlds, but also learning more about others that spark the imagination and set up the possibility of even more thrilling discoveries in 2020 and beyond.