2019 has seen some astonishing scientific breakthroughs, from the creation of the first ever image of a black hole – a feat once thought impossible – to the use of DNA splicing technology to treat sickle cell disease.
As the year comes to an end, three of our regular science contributors – Daniel Holz of the University of Chicago, Rabiah Mayas of the Museum of Science and Industry and Mark Hammergren of the Adler Planetarium – share what they regard as the most significant science stories of the year.
Here are the stories they selected.
Daniel Holz: First ever image of a black hole
In April, an international astronomical team called the Event Horizon Telescope Collaboration produced an image of a black hole for the first time.
Because not even light can escape from the immense gravity well that is a black hole, the idea of imaging a one was once thought impossible. Holz explained that the image the Event Horizon Telescope team produced is actually of super-heated matter about to fall into the black hole.
“We are not looking at the black hole itself, what we are doing is seeing stuff fall into the black hole and that stuff gets very, very hot – superheated because of the strong gravity – and then it glows,” said Holz. “And what we are seeing is that glow but in the center nothing is glowing and that’s because there’s a black hole there.”
Mayas noted the years of hard work and international collaboration that created what has already become an iconic image. The team used telescopes around the world to, in effect, create one huge telescope the size of the Earth to create the image.
“There were scientists and engineers and astronomers from across the globe that came together to generate this image,” said Mayas. “The shear technology and the instrumentation and the collaboration that led to that is another example of what a career in STEM can look like for young people.”
Rabiah Mayas: Gene-edited cells used to treat sickle cell disease
Researchers at the Sarah Cannon Research Institute in Nashville, Tennessee, announced in November that they had used genetically edited cells to treat sickle cell disease – a painful and until now incurable condition that impacts millions of people in the United States and around the world.
Doctors used cells from a patient’s bone marrow that had been modified using CRISPR cas9 gene-splicing technology and reintroduced the cells back into the patient’s body.
“CRISPR cas9 is something that was identified in bacteria as part of a bacteria’s natural immunity,” said Mayas. “The way that CRISPR works is that it looks for specific regions of DNA – so the genetic information in the cells of many organisms – and recognizes the particular sequence. And cas9 is an enzyme that can cut it. So it cuts the DNA, makes a break, and then your cell can put those ends back together.”
“CRISPR in this case was used to genetically modify the version of hemoglobin – which is the protein that is malformed in Sickle Cell and turn it into a different form that is functional,” said Mayas.
Within a month, those cells were producing healthy hemoglobin.
Mark Hammergren: Artemis moon mission
NASA is returning to the moon much sooner than it originally planned.
At the direction of President Donald Trump, NASA has been asked to accelerate its Artemis mission and return humans to the moon’s surface by 2024. The original Artemis schedule would have put humans back on the moon by 2028.
“President Trump and his administration have proposed accelerating this return to the moon and came out and said we are going to land humans on the moon – a man and a woman on the moon by 2024. And that is the directive given to NASA,” said Hammergren. “Regardless of what you think of these plans this is a directive to NASA that NASA has to follow.”
Mayas noted that although the Artemis mission is to the moon, it is also regarded as a way to answer key questions and test and prove technology that could one day take humans to Mars.
“What does it mean to spend time on another solar body? What does it mean to look for water and develop systems on a place that is not Earth in preparation for Mars?”
All: Climate change
“Climate change is the defining challenge of our time,” according to United Nations Secretary-General Antonio Guterres.
Guterres noted in an introduction to the latest report of the UN’s Science Advisory Group, released in September, that the “climate is already changing and highlights the far-reaching and dangerous impacts that will unfold for generations to come.”
All three of our scientific contributors believe that climate change is one of the top science stories of the year.
“I think young people have been telling us for years that they have been concerned about climate change,” said Mayas. “Young people from indigenous cultures around the world, from black and other marginalized communities in this country and elsewhere have been screaming for a while about climate change in part because we know from data that certain communities suffer the consequences of climate change more than others.”
Hammergren said that as a planetary scientist “we have to consider the Earth as a system as a whole” and that he had seen directly the increase in carbon dioxide in the atmosphere in his astronomical observations.
Holz noted the evidence for global warming was “overwhelming at this point.”
“The last few years have shown – just look at the news – the wildfires, the storms, the rising sea levels – it’s just this whole parade of disasters. And this is just the beginning,” said Holz. “I fear for the future.”
But Holz also noted that it’s not yet too late to try and address some of the worst impacts of climate change, particularly as young people around the world have rallied around this issue.
“It’s not too late, we can all get involved there’s lots of things to do and the fact that young people are rising up. It really impacts them the most … and we should listen to them,” said Holz. “It’s somewhat embarrassing that we have to have the young, the next generation, to hold us to task.”