Astronomers Spot First Fast Radio Burst in the Milky

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News in focus government officials have said that one aim at risk of breaking the law, he says. work focusing on mainland China — and work of the new security law is to stop them. A foreign researcher who studies science on existing data sets, rather than generating Because the security law hasn’t yet been and ethics at a university in Hong Kong, who her own — to avoid the risk of her work being drafted, it is not clear how it will be imple- requested anonymity for fear their comments classified as subversive under the security law. mented or how it might affect researchers’ could jeopardize their work visa, says they “This is what I can do at this moment,” she says. lives. no longer feel able to criticize the science Wong doesn’t view the changes she’s making The heads of the governing councils of Hong and technology practices of the central as bad, but, rather, as an opportunity to meet Kong’s eight publicly funded universities have new collaborators and learn new things. expressed support for the new bill, and say “Academics in universities will be able to continue research No need to worry and learning once it is introduced. In a 1 June Hong Kong are very Other researchers who spoke to Nature statement, they said: “As residents of Hong concerned about don’t see any evidence that the law will affect Kong, we enjoy the protection provided by the possible changes.” research. Matthew Evans, dean of science at state, and in turn have a reciprocal obligation the University of Hong Kong, says he’s seen to protect the state by supporting the intro- no indication that publishing research on duction of legislation which prohibits criminal government while living in Hong Kong. They politically sensitive topics or participating acts that threaten the existence of the state.” worry that the security law could bring the risk in international projects and grants will be But some academics are concerned that of prison sentences for such criticisms. “Even restricted under the law. the law could allow the central government science can be politicized,” they say. One thing that Evans does think could affect to interfere with independent research in Another researcher, Natalie Wai-man Wong, science in Hong Kong is the US government’s the name of national security. “Academics in a visiting environmental researcher at the City announcement of its intent to remove the Hong Kong are very concerned about possible University of Hong Kong, says she doesn’t city’s special policy status, which includes changes,” says an administrator at a univer- think her research on environment manage- access to sensitive data. That could affect the sity in Hong Kong who requested anonymity ment and governance in mainland China, ability of scientists in Hong Kong to access because they think their university is under Hong Kong and Taiwan is particularly sensi- US research data from institutions such as pressure to publicly support the security law. tive. But she has decided that she will do less NASA, he says. They worry that a national security law could be used to restrict the publication of sensitive research, such as studies on the new corona virus. Scientists on the mainland need government approval to publish research relating to the origins of the pandemic. ASTRONOMERS SPOT A Hong Kong-based editorial-board mem- ber for a scientific journal who also requested FIRST FAST RADIO BURST anonymity because they need permission to speak to the press, says they are worried that IN THE MILKY WAY foreign research grants or international collab- orations — particularly with the United States The burst came from a nearby star — and provides a — could be defined as foreign interference and restricted under the law. close-up view of one of astronomy’s biggest puzzles. When asked about researchers’ concerns, Hong Kong’s Education Bureau noted that By Alexandra Witze in the Netherlands. “But it’s by far the most the laws that safeguard academic freedom promising piece of evidence that we’ve found.” and institutions’ autonomy will remain. “It or a fraction of a second in late April, a Preliminary papers describing the burst is counterproductive and not conducive to hyper-magnetized star in the Milky Way have flooded the arXiv preprint server. the pursuit of academic excellence by Hong blasted out radio energy. Now scientists Until now, the closest known fast radio burst Kong’s universities to demonize the National say that this sudden, strange blip could happened around 150 parsecs (490 million Security legislation and to create unfounded help to explain one of astronomy’s light years) from Earth. This magnetar is in and unnecessary fear in the academic circle,” Fbiggest puzzles: what powers the hundreds our Galaxy just 10,000 parsecs away, making the bureau said in an e-mail to Nature. of other mysterious fast radio bursts (FRBs) it close enough for astronomers to have a great that have been spotted much farther away in view as it sizzles with activity. “Here is some- Risk of self-censorship the Universe. thing that gets close to the insane intensity of Some academics think that one of the greatest The event is the first fast radio burst — brief, cosmic FRBs, but that is happening not so far effects the new law will have on research will powerful cosmic flashes that flare for milli away,” says Sarah Burke Spolaor, an astronomer be an increase in self-censorship. Research- seconds — to be detected in the Milky Way. at West Virginia University in Morgantown. “It’s ers are already wary about making comments The star it came from, called SGR 1935+2154, a fantastic opportunity to learn about at least or publishing research that could upset the is a magnetar — a dense, spinning ember left one of the sources that could be causing FRBs.” central government — work that could dis- behind after a supernova, wrapped in intense tress financial markets, for example, such as magnetic fields. Many astronomers think that Cake-tin telescope negative results from a large vaccine trial, says fast radio bursts come from magnetars, but The show began on 27 April, when satellites Shekhar Madhukar Kumta, an assistant dean haven’t been able to show the link. including NASA’s Neil Gehrels Swift Observatory of education for the medical faculty at the “I wouldn’t say it’s the nail in the coffin spotted γ-rays streaming from SGR 1935+2154. Chinese University of Hong Kong. Under the that we’ve figured out that fast radio bursts The star is one of about 30 known magnetars in new law, even more researchers are likely to come from magnetars,” says Emily Petroff, an the Milky Way; these occasionally go through be worried about this, whether or not they’re astronomer at the University of Amsterdam spurts of activity during which they emit

the magnetar somehow produces the burst. Astronomers might be able to narrow down these possibilities by studying both the radio burst from SGR 1935+2154 and bursts in other wavelengths of light that happened simulta- neously, says Laura Spitler, an astronomer at the Max Planck Institute for Radioastronomy in Bonn, Germany. Several satellites detected X-ray bursts from the magnetar at around the same time as the radio emission. It is the first time astronomers have seen these signals in other wavelengths; seeing them was possible only because the magnetar is so close to Earth. But some mysteries remain. For one thing, the 28 April burst was about 1,000 times less energetic than are fast radio bursts seen in distant galaxies. And some distant bursts repeat at intervals, which can’t be easily explained by the bursts coming from a magnetar. Astronomers still want to collect as many examples of fast radio bursts as they can. “Each

ESO/L. CALÇADA ESO/L. serves as a kind of backlight shining through all An artist’s impression of a magnetar. the material between us and the source,” says Jason Hessels, an astronomer at the University radiation at different wavelengths. The next outbursts. One idea about the source of these of Amsterdam. Scientists have recently started day, the Canadian Hydrogen Intensity Mapping outbursts is that something happening inside to use that information to map the distribution Experiment (CHIME) radio telescope in the magnetar — such as a ‘starquake’, analo- of matter in the Universe. Penticton, Canada, detected a huge radio flash gous to an earthquake — could crack its surface “There’s an exciting future to the field,” says occurring to the side of its field of view — from and release energy. Another possibility is that Hessels, “even if this is more or less the answer the place where the magnetar lay (The CHIME/ the highly magnetized environment around to where the bursts are coming from.” FRB Collaboration. Preprint at arXiv https:// arxiv.org/abs/2005.10324;2020). The CHIME team had been hoping to pick up radio emission from SGR 1935+2154. But they were expecting faint radio pulses. Instead, “we got something much more exciting”, says INFLUENTIAL PANDEMIC Paul Scholz, an astronomer at the University of Toronto who led the analysis. SIMULATION VERIFIED BY A second research team got even luckier by catching the intense burst full-on. The STARE2 CODE CHECKERS radio telescope is made of low-tech antennas — each consists of a metal pipe with two cake Model shown to be reproducible after software tins attached — at two locations in California and one in Utah. STARE2 has been observ- engineers called the underlying code ‘a buggy mess’. ing the sky since last year, hoping to catch something resembling a fast radio burst in By Dalmeet Singh Chawla misapprehensions about the code, and shows the Milky Way. On 28 April, it did exactly that, that others can repeat the original findings. detecting the same radio pulse that CHIME saw otally unreliable.” “A buggy The new test is “the best possible verifica- (C. D. Bochenek et al. Preprint at arXiv https:// mess.” Over the past month, tion of Ferguson’s simulations given the state arxiv.org/abs/2005.10828; 2020). software engineers have sharply of the art in computational science”, says “I was so excited that it took me a little bit criticized the code underpin- Konrad Hinsen, a computational biophysicist of time to open up the data and inspect it, to ning an influential coronavirus at the French national research agency CNRS in make sure it was real,” says Chris Bochenek, a “Tsimulation by scientists at Imperial College Paris, who was not involved in the work. In May, graduate student at the California Institute London, one of several models that helped to he wrote in a blogpost that the study’s code of Technology in Pasadena who works on sway UK politicians into declaring a lockdown. looked “horrible”, but that such shortcomings STARE2. Some media articles even suggested that the are expected in code written by scientists who simulation couldn’t be repeated by others — aren’t specialists in software development. Energy outburst casting further doubt on the study. Now, a Released in mid-March, the original study The radio flash is by far the brightest ever seen computational neuroscientist has reported reported that there could be half a million UK from a magnetar in the Milky Way, and could that he has independently rerun the simulation deaths if nothing were done to stop the virus, offer clues to what causes fast radio bursts and reproduced its results. and modelled how policy interventions might seen elsewhere in the Universe. The successful code testing isn’t a review help (N. Ferguson et al. ‘Report 9’ http://doi. Because magnetars are spinning quickly of the scientific accuracy of the simulation, org/ggqtdx; 2020). But Imperial scientists did and have powerful magnetic fields, they have produced by a team led by mathematical epi- not make the code available for public scru- huge reservoirs of energy that can produce demiologist Neil Ferguson. But it dispels some tiny. When a cleaned-up version was released