Humanity took several significant leaps forward in the world of science this year, with two huge accomplishments in space exploration leading the way.

Scientists also made huge strides in genetics and medicine, while archaeologists uncovered new pieces of our species' ancient evolutionary history.

Here’s a look at some of the most significant scientific breakthroughs of 2015.

1. Water on Mars

Mars water

NASA researchers have finally answered the second-most asked question about Mars: Is there liquid water on the red planet?

We now know with near-certainty that there is, at least in the planet's summer months, based on data gathered by NASA’s Mars Reconnaissance Orbiter.

NASA announced the discovery on Sep. 28, ending decades of speculation. Frozen water had been confirmed on the planet back in 2008, but this was the first time rivulets of liquid water were identified.

"Mars is not the dry, arid planet that we thought of in the past," said Jim Green, NASA's director of planetary science.

Liquid water is thought to be one of the keys to answering that other, most-asked question about our planetary neighbour: Is there life on Mars?

It's also a key ingredient for potential manned missions to Mars, as water can be used for drinking, producing oxygen and making rocket fuel. NASA hopes to land humans on Mars sometime in the 2030s.

NASA had another Martian revelation in November, when it announced that Mars' atmosphere seems to have been stripped away by solar winds.

2. CRISPR technique allows gene editing

Gene editing

What if you could alter the genetic recipe for creating a plant, an animal or a human?

That science-fiction proposition is now startlingly close to reality, after a tremendous year of discovery using the new CRISPR gene-editing tool. The tool allows experts to edit genes with never-before-seen precision, using a chemical process to cut-and-paste the DNA of any living thing. That opens the door to all kinds of potential medical and biological breakthroughs, from treating cancer and HIV to mucking around with animal genes to make them more disease-resistant. However, it also introduces a whole host of ethical issues, with the possibility of editing human genes now very much in reach.

China leapt into the thick of that ethical debate this year, when researchers from that country announced they had deliberately edited the DNA of nonviable human embryos from a fertility clinic.

The fear among many scientists is that tinkering with human embryos could lead to a future of "designer babies," when parents would be able to select specific traits they want present in their unborn child.

Several top scientists met earlier this month to discuss the ethics behind CRISPR, which is already seeing widespread use within the scientific community.

The influential U.S. journal Science named CRISPR the breakthrough of the year.

3. New Horizons reaches Pluto

New Horizons' photo of Pluto

On July 14, NASA's New Horizons probe successfully completed a flyby of the dwarf planet Pluto, nine-and-a-half years after it launched form Earth. Pluto was the last (now dwarf) planet in the solar system to be visited by a NASA probe.

The spacecraft passed within 12,400 of Pluto's surface at 49,000 km/h, snapping a ream of pictures that it then beamed back home.

The photos revealed signs of recent geological activity on the dwarf planet's surface, including a young mountain range and nitrogen glaciers blanketing parts of the distant world.

Pluto atmosphere, surface features

New Horizons also captured photos of Charon, Pluto's largest moon, before setting course for its next destination: an asteroid at the edge of the solar system.

4. Canadian-developed Ebola vaccine proves effective

Ebola Vaccine

Necessity can be the mother of invention, so when a devastating Ebola outbreak hit West Africa, the need was great enough for scientists to rush development on a vaccine for the deadly virus.

Canada's National Microbiology Laboratory developed the vaccine and successfully demonstrated its effectiveness of its vaccine in July of this year. The vaccine – dubbed rVSV-ZEBOV and produced by Merck – proved effective in 100 per cent of people involved in a study in Guinea. It offers protection within six days, although it's unclear how long that protection lasts.

The vaccine helped the World Health Organization get the Ebola outbreak under control by the end of the summer.

5. First new antibiotic developed in 30 years


Doctors have been fighting bacterial infections with the same arsenal of antibiotics for a long, long time, and over that time, those infections have learned to fight back. Diseases like tuberculosis and Staphylococcus have developed resistances to some of the more commonly-used antibiotics, and the worry is that soon, other illnesses will mutate similar defenses, spawning an era of "superbugs."

But humans made a breakthrough in the fight against disease early this year, with the discovery of a new antibiotic called Teixobactin. Scientists at Northeastern University in Massachusetts successfully used the drug to treat mice infected with drug-resistant diseases, and hope to begin human trials within the next two years. If effective, the antibiotic could become an effective means of killing many drug-resistant diseases.

Teixobactin was developed by inserting an electronic chip into bacteria-laden soil.

6. 'Home-brewed' painkillers

Generic pills, painkillers, medications

Canadian and U.S. researchers announced in May that they have developed a way to "home brew" the chemical building blocks of painkillers such as codeine and morphine, using genetically modified yeast.

Most painkillers are currently produced by harvesting rare chemicals from government-regulated plants such as the poppy, but this breakthrough could make it easier to produce the drugs on the cheap. However, the study has raised some big ethical concerns over the potential that drug-producing yeast could fall into the hands of the drug trade, thereby making it easy for dealers to produce vast quantities of addictive substances.

7. Ancient fossils shed light on human ancestors


Researchers made two major fossil discoveries in 2015, which help trace out humanity's evolution through the ages.

In March, scientists announced they had discovered the oldest known fossil of a human ancestor, thought to be about 2.8 million years old, in Ethiopia. They've traced the fossil, a jawbone, back to an early point on humanity's evolutionary tree, shortly after it diverged from our more ape-like ancestors.

Two months later, it was revealed that another, even older set of pre-human fossils had been discovered, dating back an estimated 3.3 million to 3.5 million years. The fossils were the lower jaw, jaw fragments and teeth of Australopithecus deyiremeda, one of the species thought to have contributed to the evolution of humans in Africa.

It's still unclear how this ancestor fits into humanity's evolutionary history.

Then, in September, the discovery of another ape-like creature was announced, after a large collection of bones was found in a South African cave. The remains belonged to a creature dubbed homo naledi, which demonstrated a mix of human and ape-like traits.


Experts called the remains "weird" and "bizarre," and were not sure whether it is a direct ancestor of humans.

8. MRSA treatment rediscovered in ancient text

The British Library Bald's Leechbook

Call this one a breakthrough 1,000 years in the making.

A university professor in Britain has deciphered an ancient (and disgusting) method for treating eye infections that researchers say is as effective, if not more so, than modern antibiotics.

The concoction is made from a stomach-churning mix of garlic, wine, leeks and cow’s bile, and it only works if it’s left to stand in a brass container for nine days.

The mixture was found to be highly effective at wiping out MRSA, a bacterial strain that causes thousands of infections often occurring in hospitals.

The ancient potion was found in “Bald’s Leechbook,” a ninth-century textbook written in Old English and preserved in the British Library.

9. Canadian implant grants perfect vision

Bionic Lens

In cyborg news, a Canadian optometrist developed an eye implant this year that could eliminate the need for glasses altogether, while bestowing the patient with better than 20/20 vision.

B.C.'s Dr. Gareth Webb unveiled his Bionic Lens in May, with the promise that it can grant perfect vision "no matter how crummy your eyes are."

The lens is implanted using a procedure identical to cataract surgery, which takes about eight minutes to complete. Webb's company, Ocumetics Technology Corp., spent eight years and about $3 million developing the lens.

The Bionic Lens could be available as early as 2017, pending clinical trials.

10. Cancer testing on a drop of blood

Blood test generic

Scientists developed a test this year that will allow them to identify many different types of cancers in a person, using just a single drop of blood.

Researchers at the University of Victoria announced on Nov. 17 that they had developed the new testing method, and that it was already being used to test for thyroid cancer at the Mayo Clinic in the U.S.

The test entails collecting a drop of blood on a piece of filtered paper and running it through a battery of tests at a laboratory. The tests can detect markers for cardiovascular diseases, diabetes and signs of ovarian and prostate cancers.

A team of Swedish-based researchers at Umea University also announced in November that they have come up with a test to detect cancer, using only a single drop of blood. Their test uses ultraviolet light to measure damage to DNA in white blood cells.