If you're an astronaut, you're used to being treated both like royalty and like a lab animal—imperial guinea pigs, perhaps. Next year, these august examinees will enroll in a new kind of experiment as they strap themselves into the first private, human-ready spacecraft to lift off of US soil.
That's not the only historic event to expect in 2020. Back on land, actual lab rats may find the year brings them something of a reprieve. Building on mountains of work, scientists have crafted beating mini-hearts and other realistic organoids that may now replace some rodents. Throw in advances in the hunt for dark matter (if you're in xenon sales, this is your lucky year), an out-of-this-world plan for satellites, and the Crispr'ing of just about everything, and the year ahead is shaping up to be delightfully sci-fi.
Over the past decade and a half, scientists have gotten pretty good at turning stem cells into itsy-bitsy versions of nearly every one of your internal organs. At last, these lab-grown brain balls, mini-hearts, and gut globules (to name a few) are living longer, getting more complex, and starting to fulfill their promise as a replacement for animal testing. (They’ve even gone to space!)
In May, scientists in the Netherlands built proto-proto-kidneys from a cystic fibrosis patient’s urine and then tested different drugs on them. Earlier this month, researchers in California reported that their 10-month-old mini-brains have started sparking out brain waves similar to those of a developing fetus. (Brain organoid ethics, here we come!) A number of startups are also growing people’s tumors and screening them against dozens of cancer drugs to find one that works.
Those aren’t the only signs of organoids’ rise. In 2019, AstraZeneca teamed up with a company that makes tiny, beating “hearts in a jar” to improve its odds of finding a treatment for a common kind of cardiac failure. GlaxoSmithKline partnered with another heart-on-a-chip company to predict how drugs for other diseases might negatively affect the cardiovascular system. As organoids mature and Big Pharma buys in, they might just make the whole business of drug-making safer, cheaper, and less cruel. —Megan Molteni
Physicists have struggled with the question for centuries: What is the universe made of? Currently, they’re grappling with the mysteries of dark matter—an invisible material never yet observed, but whose gravitational influence suggests it comprises 85 percent of the universe’s mass—and dark energy, a substance permeating space that is stretching the universe apart at increasingly faster rates.
Next year, scientists are throwing newer and bigger machines at these questions. Dark energy researchers are installing a new telescope called the Dark Energy Spectroscopic Instrument at Kitt Peak Observatory, in Arizona. In April, it will begin to map the motion of galaxies across a third of the sky. Physicists are hoping that these maps, taken over five years, will lead to better measurements of the universe’s expansion, which they can use to infer properties of dark energy.
Meanwhile, dark matter hunters have enhanced an old detector design: an underground vat of liquid xenon, shielded from the noise on Earth’s surface, that’s designed to produce light should a dark matter particle make contact. The first prototypes were built over a decade ago and contained less than 50 pounds of xenon. To put that in perspective, the XENON1T detector in Italy is currently undergoing an upgrade to hold 8 tons of the stuff. What’s more, next summer physicists will turn on an even bigger machine, the 10-ton LUX-ZEPLIN, located in an old South Dakota gold mine. More xenon increases the likelihood of catching a dark matter particle—and they’ve got their fingers crossed. —Sophia Chen
It wasn’t that long ago that solar power in the United States was virtually nonexistent. In 2007, solar accounted for just 1/10 of 1 percent of America’s electricity, and today it’s up to nearly 2 percent. America’s solar boom grew out of two trends. The first was the plunging cost and efficiency gains of photovoltaic cells. The other was a tax credit that allowed businesses and individuals to deduct 30 percent of the cost of installing new solar panels from their taxes. Although photovoltaics continue to gain efficiency, the fate of the tax credit is uncertain. The 30 percent tax deduction drops to 26 percent in 2020 and 22 percent in 2021. After that, individuals won’t receive any tax credits for installing solar on their homes, and business owners will receive a paltry 10 percent. In July, a trio of Congressmen introduced a bill that would extend the credit at 30 percent for another five years, but so far there’s no indication it will get passed. The solar industry will survive either way, but it likely won’t see the kind of growth it has experienced over the past 10 years. The US is already struggling to meet its climate goals, and a step down in credits for solar energy isn’t going to help. —Daniel Oberhaus
Crispr, the revolutionary gene-editing tool, is less than a decade old. With astonishing speed, it has begun to appear in clinical tests, where it is now proving its powers. The first published report of Crispr in a person showed it could safely treat (though not yet cure) HIV. A highly anticipated clinical trial in the US has dosed its first patients with Crispr-edited cells to treat sickle cell disease. Next year, the list will grow longer. Doctors are recruiting patients for at least a dozen clinical trials, with aims to cure other blood disorders, inherited blindness, and a variety of cancers. They are also eyeing trials for muscular dystrophy, cystic fibrosis, and other genetic diseases for which Crispr has already shown promise in the lab.
These clinical forays all involve the original version of Crispr—a programmable enzyme that cuts DNA. There are now Crispr versions 2.0 and 3.0, which are progressing rapidly. In 2017, Harvard chemist David Liu debuted base editors—which swap out a single DNA letter for another. By the summer of 2019, more than 100 experiments with base editing had been published. A few months later Liu introduced another Crispr operating system upgrade—prime editing—which acts like a word processor, rewriting whole chunks of a DNA sequence.