The (Ultimate) Top Ten Science Stories of 2019
The year 2020 is underway! But before we chug along through yet another new year (and decade), let us pause and look back at the top science stories of 2019, determined by aggregating other "top science story" lists from only reputable sources.
Our methods remain the same as past years: We performed a Google search for "top science stories" lists, selecting only those from go-to RCS sources. Points were awarded to each story based on its ranking. For example, on a typical "top ten" list the #1 story earned ten points, #2 earned nine, #3 earned eight, and so on. Lists that had fewer than ten rankings were normalized to a 10-point scale. For the lists that did not rank the stories, each story earned 5.5 points, which is the average score if you add together all the digits from 1 to 10 and divide by ten.
1. Astronomers Capture the First Direct Image of a Black Hole's Event Horizon (35 points)
It was predicted for a couple of years now, and in 2019, it finally happened. An international consortium of scientists linked radio telescopes from across the globe to form an unprecedented virtual telescope called the Event Horizon Telescope, and with this device, they imaged a black hole's event horizon, the boundary from which light cannot escape. Where once black holes were only pictured through artist illustrations, we now have a genuine portrait of one upon which to focus our collective wonder and awe.
2. Google Claims to Have Achieved "Quantum Supremacy." (22 points)
In October, Google engineers tasked their superconducting quantum processor called "Sycamore" with checking the randomness of a large sequence of numbers. It buzzed through the work in a paltry three minutes and twenty seconds. According to Sycamore's creators, it would have taken the most powerful classical computer in existence over 10,000 years to complete the task. IBM, a competitor to Google, disagreed, saying the classical supercomputer would only need 2.5 days.
Does Google's success truly signify that quantum computers have left classical computers in the dust? That's up for debate. There's little doubt, however, that quantum computing is advancing at a blistering pace.
3. NASA's New Horizons Spacecraft Buzzes a Distant Object in the Kuiper Belt (21 points)
You'd be forgiven for forgetting this one as it occurred all the way back in January 2019. NASA's New Horizons spacecraft snapped close-up images of 2014 MU69, nicknamed Arrokoth, a 36-kilometer-wide object roughly 6.6 billion kilometers from Earth in the Kuiper Belt, a region in the outer solar system. New Horizons previously returned stunning images of everybody's favorite dwarf planet – Pluto.
4. The Denisovans Revealed (19 points)
Ancient human ancestors like Neanderthals and Homo erectus have captured scientists' attention and the public's imagination. This year it was the Denisovans' turn. New scientific efforts yielded two pieces of a skull in a Siberian Cave and showed us the possible face of a young Densiovan girl reconstructed from her DNA. Another study also hinted that Denisovans and modern humans may have interbred as recently as 15,000 years ago. The Denisovans separated from Homo sapiens' lineage an estimated 600,000 - 700,000 years ago, but today, they seem closer to us than ever before.
5. CRISPR Enters Clinical Trials and Gene Editing Advances (18.5 points)
This year, researchers began clinical trials in the U.S. testing CRISPR/Cas9 on human subjects. They hope the gene editor will be effective against cancer, blood disorders, and inherited blindness, confirming the immense potential the technology offers.
Another team, primarily based at the Broad Institute, demonstrated what could possibly be CRISPR's "upgrade": Prime Editing. In early trials, the technique showed comparable efficacy with fewer off-target effects.
6. Climate Activism Goes Global (16 points)
Tens of millions of people took to the streets in 2019 to call for action on climate change, most notable among them a seventeen-year-old from Sweden, Greta Thunberg, who was named TIME's Person of the Year. Science and climatic events continue to make plain that anthropogenic climate change is occurring, yet large-scale political action that could quell the crisis has yet to take shape.
7. Amazon Fires Highlight Threats to Earth's Biodiversity (15.5 points)
Elsewhere, scientists reported that the total bird population of Canada and the U.S. has declined by three billion since 1970. In Madagascar, rare species are threatened as hungry people understandably clear forest for agriculture. A United Nations report warned that human-caused habitat destruction is the primary threat to biodiversity worldwide.
8. Measles Continues Its Comeback (10 points)
This regrettable story also made our list of 2019's top junk science. Here's what we wrote [with updates]:
"Through September, the U.S. had 1,249 reported [measles] cases, the highest since 1992. Samoa is [just emerging from] a devastating outbreak, which sickened at least [5,612 and killed eighty-one], many of them children. Globally, the first six months of 2019 produced more measles cases than any year since 2006, according to the World Health Organization. "Vaccine hesitancy" is widely cited as the primary reason for measles' deadly return."
9. A Second HIV Patient Enters Long-Term Remission (10 points)
More than 37 million people are currently infected with HIV, the virus that causes AIDS. Current widely-available treatments stem the virus' spread, reducing it to the point that it's not even transmissible, but they cannot eliminate the virus entirely. A case report published in March raised hopes that people could be freed from the shackles of HIV entirely. Thanks to a stem cell transplant, an anonymous patient achieved long-term remission from HIV, permitting them to be off antiretroviral drugs for a year and a half. It's unlikely that this method will work for the vast majority of people infected with HIV, but it's still an auspicious development.
10. Researchers Make Major Progress in Ebola Prevention and Treatment (8.5 points)
Throughout all of 2019, the Democratic Republic of the Congo grappled with the second largest Ebola epidemic on record. So far, there have been 3,380 cases and 2,232 deaths, but amidst this horrible situation, good news emerged.
As Kai Kupferschmidt reported for Science Magazine, " In a randomized trial that pitted four different drugs against each other, about 70% of the patients who received one of those two medicines survived, compared with about 50% of those given either of the other two drugs. The result was so compelling that the trial was stopped early."
More good news: scientists for the first time successfully deployed a vaccine against Ebola, Ervebo, which has proven to be nearly 100% effective in "preventing Ebola cases with symptom onset greater than 10 days after vaccination." Near the end of 2019, the Food and Drug Administration approved Ervebo for use in the United States.