As the year winds down, we wanted to take a look back at some of the top scientific discoveries that happened in 2024. From groundbreaking medical advances, major space exploration, and ancient genetics, here are some of the year's most exciting advancements.
1. HIV Prevention Drug Lenacapavir Has Shocking Results
In 2022, health organizations across the globe, including the Food and Drug Administration (FDA) in the U.S., approved the drug lenacapavir as a treatment for HIV/AIDS. In 2024, the results of two drug trials sponsored by lenacapavir’s maker, Gilead Sciences, saw that the drug had a 96 percent success rate in one trial, while the other trial showed a 100 percent success rate.
Lenacapavir can be used as a pre-exposure prophylaxis (PrEP), and would be administered as a subcutaneous shot, given twice a year. It's similar to Truvada — a once daily pill that can help prevent HIV/AIDS. Taking pills can sometimes be less effective since not everyone remembers to take them every day, making the shot a good alternative.
Lenacapavir targets HIV’s capsid protein, the shell that protects a virus’s genetic material. As more research is done on this drug, it’s possible that other vaccines that attack the capsid proteins of other viruses could emerge.
The journal Science has named this discovery the 2024 “breakthrough of the year.”
2. Completed Map of Fruit Fly Brain
In October 2024, researchers released a completed map of nearly 140,000 neurons in a fruit fly (Drosophila melanogaster) brain. This wiring diagram, or connectome, could help experts understand how human minds process thoughts, make decisions, and store memories.
The mapping process took an international research team 10 years to complete. Along with counting neurons, the team also looked at and mapped millions of synaptic connections.
To map the fruit fly brain fully, the research team removed the fly’s brain — which was about the size of a poppy seed — covered it in resin and let it harden into a block. Then, the team shaved off ultra-thin pieces of the block — thinner than human hair — and photographed each piece with an extremely high-resolution microscope.
With over a million images, the team identified neurons and synapses before using a computer program to create a three-dimensional model of the brain.
Read More: Scientists Share Mind-Boggling Insights About Human Memory by Mapping Fly Brains
3. New Super-Earth Found In a Habitable Zone
In January 2024, NASA announced the discovery of a “super-Earth” about 137 light-years away from us. The planet — TOI-715 b — may be habitable.
According to NASA, TOI-715 b is about one and a half times as wide as Earth and resides in a “conservative habitable zone” while it orbits its small, reddish star. The habitable zone describes a planet that is the perfect distance from its star so that water can remain in liquid form on its surface instead of freezing or vaporizing.
This star may also have a smaller Earth-like planet in its orbit. Though not yet confirmed, the smaller planet, TIC 271971130.02, would be the smallest known exoplanet in a habitable zone.
Researchers located both of these planets using the Transiting Exoplanet Survey Satellite (TESS).
4. Neanderthal and Human Breeding Timeline
It’s no secret that humans (Homo Sapiens) and Neanderthals at one time interbred since Neanderthal DNA has been found in human genomes. Certain studies helped shed light on where humans and Neanderthals got together, but new findings in the journal Science help pinpoint when, on the Neanderthal timeline, these two species started interbreeding.
Researchers compared segments of Neanderthal history to that of humans over different periods of time. After analyzing 59 genomes from ancient humans that lived in Eurasia between 2,000 years and 45,000 years ago and 275 genomes in modern-day humans, the team established when humans and Neanderthals lived together in Eurasia. The results indicated that the two species lived side by side for about 7,000 years — from 50,500 years to 43,500 years.
The researchers agreed on a medium date of 47,000 years ago.
Read More: Reconstructing the World Where Homo Sapiens and Neanderthals First Got Together
5. CRISPR and AI Team Up
Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology allows for geneticists to cut and edit specific parts of DNA strands. This could help treat people with genetic disorders.
Emmanuelle Charpentier and Jennifer Doudna won the Nobel Prize in 2020 for creating the CRISPR/Cas9 genetic scissors, a tool that could help change countless lives. Now, this technology may be getting an artificial boost.
Researchers are hoping to implement large language models (LLMs) similar to the artificial intelligence (AI) behind ChatGPT. The team at Profluent is calling the new technology OpenCRISPR-1 and has made the gene editor open-source so that other research teams worldwide can access it. They also emphasize that their creation is for ethical use only. AI could help make gene editing more accurate and safer.
6. Detecting Cognitive Decline With a Blood Test
Alzheimer’s is a cruel disease for all involved. Watching a loved one slowly lose their memories, identity, and independence is painful. On top of that, testing for the disease requires a sample of cerebrospinal fluid or a PET scan (brain imaging), according to the NIH. These tests are usually not offered at a primary care office, and inconvenient hurdles can prevent patients from discovering the diagnosis and finding the right medication to slow the disease’s progression.
However, in 2024, a study partially funded by the NIH revealed that a simple blood test could accurately detect if a patient had Alzheimer’s. Researchers tested blood samples from over 1,200 older adults, some in memory care and some in primary care. The team analyzed the blood through a PrecivityAD2 test that measured amyloid beta and p-tau217. Amyloid beta accumulates in your brain due to Alzheimer’s.
The team compared the blood to the cerebral fluid and PET results and found there was an 88 percent to 92 percent accuracy. While more fine-tuning needs to be done to the blood test, this could drastically change patients' lives in the long run.
7. Oldest Known Reptile Skin Found
Fossilized remains are all we have to study the creatures that lived on Earth before us. These remains are usually fossilized bones, teeth, eggshells, and even poop. When researchers reconstruct prehistoric creatures, they usually only have skeletal remains as reference. Because soft tissue does not preserve well, finding fossilized tissue is rare.
In 2024, however, researchers uncovered what they believed to be the oldest known fossilized reptile skin. The creature lived during the late Paleozoic Era, around 20 million years ago, and may have been semi-aquatic. According to the researchers, scale evolution has not changed much in the last 20 million years. They also believed the skin could have belonged to Captorhinus aguti, an iguana-sized reptile, but they don’t know for sure.
8. The New Moons of Neptune and Uranus
Like Earth, Uranus and Neptune have their own moons. Unlike our one moon, however, these ice giants have multiple. Up until 2024, astronomers were only aware of Uranus having 27 moons and Neptune having 14. According to the International Astronomical Union's Minor Planet Center, however, three new moons are in orbit around these two planets.
Using powerful land-based telescopes — Magellan in Chile and Subaru in Hawaii — astronomers spotted two of the moons orbiting Neptune and one orbiting Uranus. The new moon in Uranus’ orbit is only about 5 miles across, likely the smallest of the now 28 moons. Astronomers also say it takes 680 days for the moon to travel around Uranus.
The new moons around Neptune are a bit larger. One is about 14 miles across and takes 9 years to complete a turn around Neptune, while the other is about 8 miles across and takes 27 years to complete orbit.
Astronomers say that these are the faintest moons ever spotted with land-based telescopes, and a special image process was used to identify them.
9. Earliest Known South American Cave Art Found in Patagonia
Cave art from our early human ancestors offers us a unique glimpse into the past. We can learn what impacted their everyday lives and what was important to their culture.
In 2024, researchers announced the discovery of pigmented cave drawings inside Cueva Huenul 1, a cave in Patagonia, Argentina, in the journal Science Advances. There are nearly 900 different cave paintings ranging from faces to geometric shapes to llama-like creatures.
The earliest paintings date back 8,200 years and range for another 3,000 years, indicating that over 100 generations may have used this cave for painting. The paintings may have had major cultural significance, and this specific cave may have been a place many generations returned to to learn about their history.
Article Sources:
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
Science. The long shot
NASA. Discovery Alert: A ‘Super-Earth’ in the Habitable Zone
Science. Neanderthal ancestry through time: Insights from genomes of ancient and present-day humans
The Nobel Prize. The Nobel Prize in Chemistry 2020
CRISPR Medicine News. OpenCRISPR-1: Generative AI Meets CRISPR
Current Biology. Paleozoic cave system preserves oldest-known evidence of amniote skin
Carnegie Science. New moons of Uranus and Neptune announced
Science Advances. Earliest directly dated rock art from Patagonia reveals socioecological resilience to mid-Holocene climate
A graduate of UW-Whitewater, Monica Cull wrote for several organizations, including one that focused on bees and the natural world, before coming to Discover Magazine. Her current work also appears on her travel blog and Common State Magazine. Her love of science came from watching PBS shows as a kid with her mom and spending too much time binging Doctor Who.
