As always, science had a great year. There have been many important discoveries and developments, and below you can find the ones that generated the most media attention.
10. Water on Mars
The existence of water on Mars has been a subject of constant debate for decades. We already knew that the planet had ice and steam, but the presence of liquid water, while likely, had not yet been established.
That changed in October when NASA announced that the Curiosity rover found evidence of liquid water flows on Mars. Scientists are unsure of the source, but know that water passes through canyons and crater walls during the summer months.
The process of analyzing this water, however, will be slow and methodical. There is concern that Earth microbes infect the site, which is why the current rover will not analyze water flows even if it finds them. The new challenge for researchers will be to develop a truly “clean” and sterile spacecraft for future study.
9. Noah's Ark Project
Despite its name, Noah's Ark Project will not gather copies of all the animals on earth - just their DNA. Researchers at Moscow State University in Russia want to build the largest genetic repository in history. The project was announced in late 2014 and started its first phase in 2015, with the hope of being completed in 2018.
Although the Russian project is the largest of its kind, there are similar ones. The Millennium Seed Bank is the largest plant conservation program, and the Frozen Ark Project in Britain stores the DNA of endangered species. In Washington, USA, the National Museum of Natural History currently houses the largest biorepository in the world, with over 4.2 million samples.
The installation of Noah's Ark Project will measure almost 430 square kilometers when completed. Cellular material will be cryogenically frozen and stored, perhaps to be used in the future to bring extinct species back to life.
8. Unpublished Photos of Pluto
Until recently, we had a limited view of Pluto; scientists had more questions than answers. We finally got some questions answered in July of this year, when the New Horizons spacecraft flew over the former planet, sending amazing high-resolution images of Pluto to Earth.
The photos provided a treasure trove of information about the dwarf planet's geographic features: mountain ranges, a heart-shaped plain called Sputnik Planum, ice flowing through valleys, and more. We also looked closely at Pluto's largest moon, Charon.
New Horizons was launched in 2006 and flew around Jupiter in 2007. After passing through Pluto, the spacecraft is now on its way to offer us an equally unprecedented look at the Kuiper Belt sometime in 2019.
7. Discovery of Homo naledi
The hominid family tree changes all the time. This year, for example, had an addition: Homo naledi, an extinct species that some scientists believe to be a member of the genus Homo. Discovered in South Africa's network of limestone caves known as the “Cradle of Humanity” in 2013, an extensive survey of 1,550 recovered skeletal pieces from at least 15 individuals took a long time to complete, so the species was only formally announced. in September 2015.
Other evidence needs to confirm the results of the study, but based on anatomical features, experts believe that the Homo naledi may have lived around the same time as the Homo erectus and Homo habilis, about two million years ago.
Anthropologists are intrigued by the positioning of the bones found, as the skeletons appear to have been moved into the cave, which would make the site a "graveyard." Burial practices for such a primitive species would be unprecedented and would certainly raise new questions about human evolution.
6. Map of the epigenome
In 2003, scientists completed one of the most ambitious projects in the history of biology: the Human Genome Project. While the genome can be seen as a map showing all the genes that make up our DNA, it is our epigenome that keeps track of all changes in the structure and function of genes.
Mapping it is much more difficult, but also more useful than mapping the genome. Understanding the functions of various cell types and, most importantly, being able to “turn them on or off” has vast medical implications. Such changes can trigger the onset of various diseases such as cancer, diabetes and Alzheimer's.
This year, scientists unveiled the first "version" of an epigenome map, a detailed collection of 111 different types of human cells. Soon, dozens of articles were published on the potential ramifications of these findings.
The mapping project is known as the “Roadmap Epigenomics Program” and will take years to complete.
5. Discovery of Kimbetopsalis simmonsae
Kimbetopsalis simmonsae It is one of the first mammals ever discovered. He roamed the earth about 65 million years ago, and is believed to have survived the extinction that killed the dinosaurs.
The anatomy and diet of this newfound species gives us clues as to how large mammals became dominant after the dinosaurs disappeared. The size of this animal is estimated at one meter in length and its weight 10 kg.
Kimbetopsalis simmonsae It was part of the multituberculates, an early mammalian group that originated during the Jurassic period and evolved along with dinosaurs. After the extinction of the dinosaurs, multituberculates thrived for 100 million years before being killed by rodents and completely disappeared.
Kimbetopsalis simmonsae it was found all over North America and Asia, and compared to others before it, it was much larger. The lack of dangerous predators and the animal's strong teeth allowed the animal to thrive for so long, feeding on the lush vegetation of the planet.
A few years ago, a carbon allotrope called graphene was announced as an excellent material. Formed at atomic scale, it is 200 times stronger than steel, almost invisible and a good conductor of heat and electricity.
In 2015, however, another product turned out to be even more promising: siliceno. The new form of silicon comes in layers just one atom thick. Theoretically, its electrical properties suggest that it can be used to make extremely small and powerful computer chips. But in reality, working with this material is very difficult.
In February, scientists succeeded in creating the world's first silicon transistor. The joint effort between American and Italian researchers was detailed in the journal Nature. According to performance tests, transistors have demonstrated their theoretical potential. Even so, scientists still do not know whether this method is commercially viable on a larger scale. If so, it could replace graphene as the “future of nanotechnology”.
3. The plant that tastes like bacon
Bacon is loved and condemned in our society, precisely because it is not the healthiest food in the world. But what if there was a good kind of bacon for you? It would be a kind of gastronomic holy grail!
Thanks to researchers at Oregon State University, this dream can come true. They discovered a type of algae called dulce, commonly found in the Atlantic and Pacific coastal areas. Harvested and eaten for centuries, it is not a novelty in itself. It is known to be a “superfood,” the kind that is loaded with nutritional value. Compared to cabbage, its most famous competitor, has twice as many nutrients, for example.
What the scientists discovered while studying new strains of dulce was that when fried it tastes very similar to bacon. Researchers say there is great potential for this new strain of kelp to become a very popular food that is as tasty as it is healthy.
2. Bring the mammoth back to life
Genetic engineering is one of the most controversial fields of scientific research. One of its techniques is known as CRISPR, and can be used to modify one gene, multiple genes, and theoretically even an entire genome.
Some scientists believe it could prevent the aging process. Others think it should be used to modify entire species of problem animals such as pests. CRISPR can also be used for “de-extinction”, ie to bring extinct species back to life.
Scientists are already trying something like that by inserting woolly mammoth DNA into cells of Asian elephants, their closest relatives. By the end of 2015, we simply have some healthy elephant cells with mammoth DNA. But this is already a step forward in reviving a missing animal 3,300 years ago.
1. The mysterious megastructure
In September, astronomers announced the discovery of a peculiar star named KIC 8462852. It exhibits curious behavior in the form of unpredictable and erratic light fluctuations.
Light from a star can be blocked by objects at regular intervals, which can be predicted once you learn the orbital pattern of the star. This was not the case with KIC 8462852.
Researchers know that it is not a planet that is causing such fluctuations, because even a giant planet like Jupiter only dims the sun's brightness by 1%. The star experiences a 22% light decrease.
Other theories to explain this bizarreness include a cloud of dust and debris, a series of comets, an irregularly shaped star and… a mega-structure created by aliens.
To be fair, these kinds of giant structures were theorized by scientists long ago. Something called the “Dyson Sphere” could hypothetically be built by an advanced civilization to use the star as a source of energy.
We are almost certain that aliens are not the most likely explanation for this mystery, but we cannot yet completely dismiss this theory.