It's been an incredibly busy year in space exploration full of amazing discoveries, the capturing of unprecedented imagery, the emergence of bold new theories and the occasional mission failure.

For some it might seem like humanity has lost its appetite for adventurous space missions since the glory days of the Apollo missions and the Moon landing. But nothing could be further from the truth as 2016 provided some truly monumental moments from our continued push into the final frontier.

Here are some of the most exciting.


Thanks to NASA's Kepler Telescope which has been busily scanning 150,000 stars for signs of orbiting bodies in recent years, we've discovered that on average every star has at least one planet if not many more circling it.


In May, the US space agency revealed it had found a further 1284 new planets, more than doubling the number of known exoplanets in the universe. And the most important part: nine of them could theoretically be habitable.

"This announcement more than doubles the number of confirmed planets from Kepler," said Ellen Stofan at the time, chief scientist at NASA Headquarters in Washington. "This gives us hope that somewhere out there, around a star much like ours, we can eventually discover another Earth."

Scientists said the calculations made this year suggest there could be tens of billions of habitable planets in the Milky Way.

Fast forward to August, and astronomers think they have the best candidate for a nearby Earth-like planet, or "Second Earth".

The planet dubbed Proxima B is orbiting our closest star named Proxima Centauri, a red dwarf star that's just four light years away.

Proxima B is orbiting in the "goldilocks zone" of Proxima Centauri, which means it's close enough to the star that water would not freeze, but far away enough so that water wouldn't boil.

Now scientists are trying to figure out a way of getting a robotic probe to the planet to see if it is home to alien organisms, although sadly it is not a mission many of us will live to see.


the Juno probe had successfully entered the orbit of the biggest planet in our solar system - Jupiter - in 2016. Photo / 123rf
the Juno probe had successfully entered the orbit of the biggest planet in our solar system - Jupiter - in 2016. Photo / 123rf

"Welcome to Jupiter."


Those were the words that ushered in a mixture of relief and celebration for NASA scientists in July as they received confirmation that the Juno probe had successfully entered the orbit of the biggest planet in our solar system.

After a tense 35-minute decent, the probe entered Jupiter's orbit five years after launching in 2011.

The data-gathering spacecraft will spend the next 14 months orbiting the planet and sucking up crucial information, giving scientists insights into questions about Jupiter's atmosphere and core.

Jupiter's composition is more of a mystery than anything else. Scientists currently believe the gaseous planet has a dense central core that may be surrounded by a layer of metallic hydrogen, with another layer of molecular hydrogen on top.

Juno will get so close to Jupiter's inhospitable environment that it will be able to study its atmosphere giving unprecedented insight into its origins as well as the origins of other planets in our solar system, including Earth.

By better understanding Jupiter's chemistry we will understand "what our solar system was like billions of years ago," NASA's Michelle Thaller said.

The huge gas planet was likely the first planet formed and had a major impact on the formation of other planets.


This year provided the most compelling evidence yet that our solar system may have a ninth planet, about 10 times the mass of Earth, lurking far beyond Neptune.

The notorious Planet 9 has not been directly observed but researchers at the California Institute of Technology used computer simulations of the orbits of several distant objects beyond Neptune to show the possible presence of the unseen planet.

"Although we were initially quite sceptical that this planet could exist, as we continued to investigate its orbit and what it would mean for the outer solar system, we become increasingly convinced that it is out there," said Konstantin Batygin who presented the computer modelling evidence in January along with fellow Caltech astronomer Mike Brown.

Even though it's believed to be 10 times the size of Earth, it has likely escaped the gaze of telescopes because it is so far away from the Sun.

In October another group of scientists added to speculation by publishing a paper in the Astrophysical journal claiming Planet 9 is responsible for the perceived tilt of the Sun.

Some scientists have even predicted we will find the elusive Planet 9 within 16 months.


Photo / 123rf
Photo / 123rf

There are at least two trillion galaxies - 10 times more than scientists thought - that exist within the observable universe. And we can't even see most of them.

The unfathomable dimension and contents of our world never cease to amaze, and this year scientists showed you can never underestimate the universe.

Using the Hubble Space Telescope a group of international astronomers compiled 20 years of images from the observatory, and other international observatories, to create a 3D model of the 200 billion galaxies already estimated to exist.

But the model instead revealed that there are at least one trillion eight hundred billion more out there. Only 10 per cent of these are visible to us even with our strongest telescopes.

"It boggles the mind that over 90 per cent of the galaxies in the universe have yet to be studied," said Christopher Conselice, who led the study published in October in The Astrophysical journal.


Sadly not all the efforts of space exploration this year were triumphs.

Once again, Mars proved a tricky beast for Europe's space agencies to conquer. In October the ESA and the Russian space agency tried to put an exploratory lander dubbed Schiaparelli on the surface of Mars.

Instead they lost contact with the lander and after days of worried suspense they concluded it crash landed on the planet's rocky terrain.

Pictures later taken by NASA's Mars Reconnaissance Orbiter showed a black spot in the area where the Schiaparelli lander was meant to touch down, confirming fear the lander had crash landed on the Martian surface in a fiery failure. The spacecraft reportedly flew into Mars at 540 kilometres per hour instead of gently gliding to a stop, after a computer misjudged its altitude, scientists said in November.

But there is a silver lining.

The botched touchdown was effectively a test run to pave the way for a larger future rover to be launched in 2020.

As such, European space officials have insisted that any problems encountered by Schiaparelli were part of the trial-run and would inform the design of the future rover.

The rover is due for launch in 2020 and will drill up to two metres deep to search for remains of past life, or evidence of current activity.

"In some ways, we're lucky that this weakness in the navigation system was discovered on the test landing, before the second mission," ESA's Schiaparelli manager Thierry Blancquaert said.


In December NASA's Saturn-orbiting spacecraft, Cassini, began an unprecedented mission to skim the planet's rings. Photo / 123rf
In December NASA's Saturn-orbiting spacecraft, Cassini, began an unprecedented mission to skim the planet's rings. Photo / 123rf

In December NASA's Saturn-orbiting spacecraft, Cassini, began an unprecedented mission to skim the planet's rings.

Launched nearly 20 years ago, Cassini will swoop down through the outer edge of rings every seven days. The spacecraft should make 20 dives through April, observing some of Saturn's many mini moons and even sampling ring particles and gases.

In September 2017 Cassini will carry out its final act by plunging into Saturn's atmosphere and will hopefully send back important data to NASA scientists before being swallowed up by the harsh celestial environment.

"This is it, the beginning of the end of our historic exploration of Saturn. Let these images - and those to come - remind you that we've lived a bold and daring adventure around the solar system's most magnificent planet," said Carolyn Porco, Cassini imaging team lead at Space Science Institute in Colorado.