Exploring the solar system—the best of what you can look out for in 2016
NASA’s Juno probe will be the fastest object humanity has ever created when it approaches Jupiter. Credit: NASA/JPL-Caltech
This year is shaping up to be another exciting one for space after a bonanza of discoveries and celestial events in 2015.
One of my hoped-for highlights of 2016, NASA’s Insight mission, has unfortunately been scrubbed due to a serious leak in last stage testing. But here are three of my particular favourite space missions to watch out for as well as some key night sky events to try and experience throughout 2016.
The first stage is a joint Trace Gas Orbiter (TGO) and Schiaparellilander which will launch in March (to arrive by October). The technologies demonstrated by Schiaparelli will then be used for a rover to land in any interesting sites identified by TGO as the next stage in ExoMars.
The orbiter will spend five years attempting to “sniff” out those gases in the Martian atmosphere such as methane that break down over time, with any trace amounts indicating a process of creation on Mars. Whether biological (that is, expelled by microbial life) or geological in nature will be investigated throughout the ExoMars programme.
A key story for 2016 will be the investigation of Jupiter by NASA’s Juno mission. As the enormous gravity of Jupiter pulls the spacecraft to ever higher speeds, ultimately travelling at more than 70km per second, Juno will become the fastest craft in human history.
It will fire its rockets to slow down and then enter one of the most challenging orbits ever attempted, skimming as low as just 5,000km above the cloud tops, ducking below the intense – and damaging – radiation belts of Jupiter to study the gas giant as never before. To put that in perspective, if Jupiter were a soccer ball, Juno would be skimming less than a centimetre off the surface.
The aim is to see if there’s water in the atmosphere (revealing the conditions from which the gas giants formed), to study the gas giant’s magnetic and gravitational field and the nature of the interior.
Thousands of kilometres of clouds crush the core to extraordinary pressures that might form a planet-sized diamond (as Arthur C. Clarke once wrote) or more likely a core of superconducting metallic hydrogen that powers the enormous magnetic field of the planet.
It will be deorbited in Februrary 2018 after 37 death-defying orbits threading through the incredibly dangerous radiation belts.
The latest telescope on Earth could hardly look more different to those that use light (be it visible or radio waves) but LIGO is searching the skies for colliding black holes, with the telltale signals as ripples in the very fabric of spacetime itself. These gravitational waves are Einstein’s final prediction and are yet to be verified.
As a gravitational wave passes through you, you’d be stretched one way becoming thinner and then as the wave continues through you are squashed and fattened. Since this doesn’t visibly appear to happen we can guess that the stretching and squashing is tiny. The expected change is less than the thickness of an atom in a ruler a million kilometres long.
To measure this incomprehensibly tiny change we use lasers (technically an interferometer bouncing two lasers back and forth) in different locations on Earth to triangulate the position to a few degrees on the sky (the width of a few full moons).
Discovering these waves will allow us to see the universe with an entirely new sense, as distinct from hearing to seeing. In 2016, humanity will gaze with entirely new eyes into the cosmos.
There are also some fantastic sights in the sky to watch out for in 2016.
Southeast Asia and Africa will get to enjoy the more visually impressive solar eclipses, with Australia, Europe and the United States missing out (although everyone can enjoy the stunning meteor showers).
These are selected from a more exhaustive list of all the motions of the planets and other celestial highlights. If not mentioned, all times and viewing directions are from an Australian perspective.
January 20 to February 20
All five planets visible to naked eye – Mercury, Venus, Mars, Jupiter and Saturn – will appear in morning sky. This is the first time since 2005 and should be something we can all manage to see without telescopes.
Jupiter at opposition
This the best time to see the gas giant as it forms a direct line with the sun – Earth – Jupiter. Similar to a full moon, Jupiter will be entirely illuminated by the sun making it appear brighter than any other time this year.
With binoculars you should easily discern the four largest (Galilean) moons sitting in a line either side of the planet.
Total solar eclipse
The total solar eclipse will be visible from central Indonesia and some Pacific Islands. Neighbouring regions, such as Northern Australia and Southeast Asia, will see a partial eclipse but protective eyewear should be used at all times. Check the NASA predicted track.
Eta Aquarids meteor shower
May 6 to 7
Eta Aquarids is a particularly good meteor shower with up to 60 meteors per hour at its peak in the southern hemisphere (the northern hemisphere might see half this). This meteor shower is from the Earth running through the dust tail of Halley’s comet.
The new moon will mean even more of the faintest shooting stars are visible. Look towards the constellation Aquarius after midnight.
Transit of Mercury across the sun
Mercury will pass between the Earth and the sun, with the dark disk of the planet visible across the face of the sun. There will not be another transit of Mercury until 2019 and then the next one will be in 2039.
This can only be seen with specialised protective eyewear and a telescope, including a pinhole camera. Unfortunately, this will not be visible from Australia but will be seen in most of the rest of the world, in particular the eastern United States and eastern South America.