2021 in science
This is a list of several significant scientific events that occurred or were scheduled to occur in 2021.
Events
January
February
March
April
May
June
July
- 1 July
- * Construction begins on the Square Kilometre Array, with first light planned for 2027.
- * In the debate about the cognitive impacts of smartphones and digital technology a group reports that, contrary to widespread belief, scientific evidence doesn't show that these technologies harm biological cognitive abilities and that they instead only change predominant ways of cognition – such as a reduced need to remember facts or conduct mathematical calculations by pen and paper outside contemporary schools. However, some activities – like reading novels – that require long attention spans and don't feature ongoing rewarding stimulation may become more challenging in general.
- * A study finds that ~9.4% of global deaths between 2000 and 2019 – ~5 million annually – can be attributed to extreme temperature with cold-related ones making up the larger share and decreasing and heat-related ones making up ~0.91 % and increasing.
- 2 July
- * The first scientific review in the professional academic literature about global plastic pollution in general finds that the rational response to the "global threat" would be "reductions in consumption of virgin plastic materials, along with internationally coordinated strategies for waste management" – such as banning export of plastic waste unless it leads to better recycling – and describes the state of knowledge about "poorly reversible" impacts.
- * Researchers report that a mix of microorganisms from cow stomachs could break down three types of plastics.
- * Scientists identify GPR75 variants as alleles protective against obesity in ~640,000 sequenced exomes.
- 5 July
- * Scientists report the discovery of a bone carving, one of the world's oldest works of art, made by Neanderthals about 51,000 years ago.
- * A scientific review summarizes evidence from nutrition research for diets for atherosclerosis prevention.
- 7 July
- * A preprint finds the SARS-CoV-2 Delta variant to cause a ~108 % increased – or more than twice as large – risk for hospitalization, a ~234 % increase for ICU admission and 132% for death compared to non-VOC variants.
- * Researchers present a programmable quantum simulator that can operate with 256 qubits.
- 8 July - Scientists report that in the past – with little relevance to future evolution – lower temperatures were associated with larger Homo body sizes and that long-term variability in precipitation was correlated with brain size.
- 10 July - Scientists report in a preprint the discovery of long extrachromosomal DNA structures, they call borgs, which appear to incorporate genes from organisms they encounter. These structures, which could turn out to be an unknown form of giant viruses or "giant linear plasmids", co-occur with a species of archaeon which may host them, shares many of their genes, whose main chromosome is only three times larger and whose capacity for anaerobic oxidation of methane as well as other biological functions – such as production of proteins – the borgs may augment.
- 12 July - Scientists report in a preprint that the viral load in the first positive test of infections with the SARS-CoV-2 Delta variant was on average ~1000 times higher than with compared infections during 2020.
- 14 July
- * Researchers report finding the earliest known fossil life on Earth, in the form of "putative filamentous microfossils", possibly of methanogens and/or methanotrophs, that lived about 3.42-billion-year-old in "a paleo-subseafloor hydrothermal vein system of the Barberton greenstone belt in South Africa."
- * Astronomers report the detection, for the first time, of an isotope in the atmosphere of an exoplanet. In specific, the isotope Carbon-13 was found in the atmosphere of a gas giant exoplanet named TYC 8998-760-1 b.
- * Researchers used a brain-computer interface to enable a man who was paralyzed since 2003 to produce comprehensible words and sentences by decoding signals from electrodes in the speech areas of his brain.
- * Researchers describe effects of deforestation and climate change in a transformation of Amazonia from carbon sink to carbon source.
- 15 July - Scientists report that the Chicxulub impactor likely was an outer main-belt asteroid, a carbonaceous chondrite C-type asteroid.
- 16 July
- * Recently thought subglacial lakes under the Southern Polar cap of Mars based on a 2018 MARSIS measurement could also be clay minerals and frozen brine.
- * Japan achieves a new world record Internet speed over ~3.000 km: 319 Tbit/s, beating a previous record of 178 Tbit/s.
- * A study concludes only 1.5-7 % of "regions" of the modern human genome to be specific to modern humans. These regions have neither been altered by archaic hominin DNA due to admixture nor are shared with Neanderthals or Denisovans according to their used genomic datasets. They also found two bursts of changes specific to modern human genomes which involve genes related to brain development and function.
- * A study using whole-genome resequencing indicates that Cannabis sativa was first domesticated about 12,000 years ago in the early Neolithic period in East Asia, with the results being consistent with a single domestication origin.
- 18 July - Journalists and researchers report the discovery of spyware, called "Pegasus", developed and distributed by a private company which can and has widely been used to infect iOS and Android smartphones often – partly based on 0-day exploits – without the need for any user-interaction or significant clues to the user and then be used to exfiltrate data, track user locations, capture film through its camera, and activate the microphone at any time.
- 19 July
- * Researchers review 217 analyses of on-the-market products and services as well as existing alternatives to mainstream food, holidays, and furnishings, and conclude that total greenhouse gas emissions by Swedes could be lowered by to date up to 36–38 % if consumers – without a decrease in total estimated expenditure or considerations of self-interest rationale – instead were to obtain those they could assess to be more sustainable.
- * Researchers report that higher exposure to woodland urban green spaces is associated with improved cognitive development and risks of mental problems for urban 15-16 years old adolescents.
- * Scientists report that wild pigs are causing soil disturbance that, among other problems, globally results in annual carbon dioxide emissions equivalent to that of ~1.1 million passenger vehicles, implying that wild pig meat – unlike other meat products – has beneficial effects on the environment.
- 20 July
- * Researchers conclude that a previously rejected abiotic origin of phosphine concentrations on Venus reported in September 2020 – high rates of active plume volcanism – could be plausible.
- * A scientific review concludes that, except for poultry, at 50 g/day unprocessed red and processed meat appear to be risk factors for ischemic heart disease.
- * Scientists report that worldwide adolescent loneliness and depression increased substantially after 2012 and that loneliness in contemporary schools appears to be associated with smartphone access and Internet use.
- 22 July
- * Astronomers using the Atacama Large Millimetre/submillimeter Array report the first clear detection of a moon-forming disc around an exoplanet; in this case, the Jupiter-like planet PDS 70c.
- * DeepMind announces that its AlphaFold AI has predicted the structures of over 350,000 proteins, including 98.5% of the ~20,000 proteins in the human body. The 3D data along with their degrees of confidence for accuracy is made freely available with a new database, doubling the previous number of protein structures in the public domain.
- 26 July
- * The Galileo Project, headed by Avi Loeb, is launched. The project seeks to gather and report scientific evidence of extraterrestrials or extraterrestrial technology – such as of UFOs/UAP with alien origins – on or near Earth via telescope technology.
- * Scientists report to have created the first complete neuron-level-resolution 3D map of a monkey brain which they scanned within 100 hours.
- * A study finds that the increasing probability of record week-long heat extremes occurrence depends on warming rate, rather than global warming level and provides projections.
- * A scientific review summarizes studies about long COVID.
- 28 July
- * The first direct observation of light from behind a black hole is reported, further confirming Einstein's theory of general relativity.
- * Metallic water is prepared for the first time in an ordinary Earth lab.
- * In an update to the World Scientists' Warning to Humanity, scientists report that evidence of nearing or crossed tipping points of critical elements of the Earth system is accumulating, that 18 of 31 planetary vital signs have reached record values, that 1990 jurisdictions have formally recognized a state of climate emergency, that frequent and accessible updates on the emergency are needed, that COVID-19 "green recovery" has been insufficient and that root-cause system changes above politics are required.
- 29 July - A study indicates gut microbiomes with large amounts of microbes capable of generating unique secondary bile acids are a key element of centenarians' longevity.
- 31 July - A kitchen robot – one of the first of its kind – for autonomous preparation of school meal program or delivery-service level amounts of discrete meals is demonstrated.