Rogue Worlds May Not Be So Lonely After All, Europa Clipper Completes Key Test, and RFK, Jr., Pulls $500 Million in mRNA Vaccine Funding

Scientific American

13 hours ago

Rachel Feltman: Happy Monday, listeners! For Scientific American 's Science Quickly, I'm Rachel Feltman. Let's kick off the week with our usual science news roundup.
Let's start with some space news. Have you ever heard of rogue planets? They sound pretty cool, and they are: the term refers to exoplanets that roam free instead of orbiting a star. Some of them may be objects that formed like stars, coalescing in the wake of a giant gas cloud's collapse but never gaining enough mass to actually start the process of nuclear fusion. Others may get their start in the usual planetary way—forming from the gas and dust around a star—before getting ejected out into open space for some reason or another.
According to a preprint study made available last month, the life of a rogue planet might not always be as lonely as it sounds. Some of them may be able to form little planetary systems of their own.
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The researchers behind the new study, which still has to go through peer review, used instruments on the James Webb Space Telescope to gather information about eight different rogue planets, each with a mass around five to 10 times greater than Jupiter's. Based on infrared observations, the scientists say, six of the objects seem to have warm dust around them, indicating the presence of the kinds of disks where planets form. The researchers also saw silicate grains in the disks—evidence that the dust is growing and crystallizing. That's typically a disk's signature move when it's gearing up to make some baby planets.
This study didn't actually find any hints of fully grown planets orbiting those giant rogue worlds, but it suggests that such a phenomenon might be possible. As wild as it is to imagine a lonely world roaming space without a star to orbit, it's even more intriguing to picture a whole system of planets spinning in the dark.
Speaking of space, NASA's Europa Clipper, which is expected to arrive at the Jupiter system in 2030 so it can study the gas giant's icy moon, has completed an important test. Back in March 2025 the Europa Clipper flew past Mars and conducted a test of its REASON instrument. That's short for Radar for Europa Assessment and Sounding: Ocean to Near-surface. This radar is a crucial component of the clipper's mission because it's designed to peek beneath the icy shell of Europa's surface, perhaps even glimpsing the ocean beneath it. The radar will also help NASA scientists study the ice itself, along with the topography of Europa's surface.
The clipper features a huge pair of solar arrays that carry the slender antennas REASON needs to do its work. The antennas span a distance of about 58 feet, while the arrays collectively stretch the length of a basketball court, which is necessary for them to gather enough light—Europa gets just around 1/25th as much sunlight as we do on Earth. The sheer size of all those components made it impossible to fully test REASON on Earth because once the flight hardware was finished, the clipper had to be kept inside a clean room. NASA simply didn't have a sterile chamber big enough to properly assess the radar.
When Europa flew by Mars on March 1, REASON sent and received radio waves for about 40 minutes, collecting 60 gigabytes of data. Earlier this month NASA announced that scientists had completed their analysis of the data and deemed the REASON instrument ready for prime time.
Let's move on to some public health news—first, vaccines. Last Tuesday, the Guardian reported that COVID cases in the U.S. are on the rise, as has been the case each summer since the start of the pandemic. Though this current surge has seen case numbers growing more slowly than in previous years, experts who spoke to the Guardian voiced concerns about what the coming months could bring.
In May, U.S. Food and Drug Administration officials wrote that, come fall, COVID boosters may be limited to older people and individuals at higher risk of getting severely ill. Even if this move doesn't outright prevent people from vaccinating themselves and their kids, public health experts are concerned that confusion around availability and insurance coverage could lead to a worrisome dip in booster administration.
Meanwhile, U.S. Department of Health and Human Services head Robert F. Kennedy Jr. announced last Tuesday that his department is canceling almost $500 million in funding for the development of mRNA vaccines. While experts say mRNA vaccines are safe, have the potential to curb future pandemics, and have already saved millions of lives, Kennedy has come out against the technology. Mike Osterholm, a University of Minnesota expert on infectious diseases and pandemic preparedness, told the Associated Press that he didn't think he'd witnessed 'a more dangerous decision in public health' in his 50 years in the field. We're hoping to focus on explaining mRNA technology in an upcoming episode, so let us know if you have any questions we can answer. You can send those to [e-mail].
In other public health news, a group of scientists say bird flu could be airborne on some dairy farms. In a preprint paper recently posted online, researchers report finding H5N1 influenza virus in both large and small aerosol particles in air sampled from California farms. The scientists also found viral particles in milk, on milking equipment and in wastewater. While H5N1 isn't currently thought to pose a major health risk to humans, its continued circulation in mammals leaves us open to potentially dangerous mutations of the virus.
We'll end this week's roundup with a fun little story about how terrifying humans are. Earlier this month the Wall Street Journal reported that U.S. Department of Agriculture workers are blasting human music and voices from speaker-touting drones to scare wolves away from livestock. Apparently the audio selections for these so-called wolf-hazing attempts include the sounds of fireworks, AC/DC's song 'Thunderstruck' and, perhaps most delightfully, that scene from the movie Marriage Story where Scarlett Johansson and Adam Driver scream at each other.
Apparently Driver and ScarJo are doing the trick: the Wall Street Journal reported that noisemaking drones were deployed in southern Oregon after wolves killed 11 cows in the area over the span of 20 days. Once the drones were in hazing mode, there were reportedly just two fatal wolf attacks on cattle in an 85-day period. There's no word yet on how the wolves feel about Laura Dern.
That's all for this week's science news roundup. We'll be back on Wednesday to talk about the latest advances in male contraception.
Science Quickly is produced by me, Rachel Feltman, along with Fonda Mwangi, Kelso Harper and Jeff DelViscio. This episode was edited by Alex Sugiura. Shayna Posses and Aaron Shattuck fact-check our show. Our theme music was composed by Dominic Smith. Subscribe to Scientific American for more up-to-date and in-depth science news.
For Scientific American, this is Rachel Feltman. Have a great week!