A scientific review produced by the i.a. NASA-sponsored online workshopTechnoClimes 2020 about mission concepts for the search of technosignatures is published. They classify signatures based on a metric about the distance of humanity to the capacity of developing the signature's required technology, associated methods of detection and ancillary benefits of their search. The study's conclusions include robust rationales for searching artifacts within the Solar system.[2][1]
2 March
Scientists report substantially more precise and regionally subdivided end times of the Acheulean, finding that it persisted long after the diffusion of Middle Palaeolithic technologies in multiple continental regions and ended over 100,000 years apart.[3][4]
A study of data on half a million U.K. citizens shows associations between meat intake with risks of some of 25 common conditions, including ischaemic heart disease and diabetes, as well as a lower risk of iron deficiency anaemia.[5][6] A study published on 31 March finds higher intake of processed meat was associated with "a higher risk of mortality and major CVD".[7][8]
Astronomers report the discovery of a quasar known as P172+18, the most distant source of radio emissions known to date, some 13 billion light years away.[19]
Scientists propose storing DNA and other biological reproductive structures in a "lunar ark" on the Moon of all 6.7 million species of plants, animals and fungi known on Earth – to help assure their survivability over the years.[20][21]
Physicists report that according to their theoretical model traversable microscopic wormholes may be possible and not require any exotic matter.[29][30] Another study published on the same day finds that humanly traversable wormholes may be possible if reality can broadly be described by the Randall–Sundrum model 2, which is a brane-based theory consistent with string theory.[31][32]
A physicist describes a way warp drives sourced from known and familiar purely positive energy could exist – warp bubbles based on superluminal self-reinforcing "soliton" waves. It may allow for up to Faster-than-light speed travel, transfers and communication with the large energy requirements possibly being reducible.[28][33][34][35]
COVID-19 pandemic: A cohort study of patients matched by similarity finds that the probability of increased mortality from VOC-202012/01 is high, increasing from 0.25 to 0.41% in the low-risk group of the database without controlling for U.K. vaccination campaign effects.[40][41] A study published on 15 March estimates the strain's mortality-risk to be ~61% (42–82%) higher than that of pre-existing variants.[42][43]
An analysis of the leaked and allegedly manipulated data about COVID-19 vaccines indicates concerns over percentage of intact mRNA in early commercial batches of mRNA vaccines, possibly reflecting a lack of certainty that relates to their efficacy at the time.[44][45]
A new microscopy technique using a hyperbolic metamaterial is shown to boost imaging resolutions, from 200 nanometres down to 40 nanometres.[46][47]
17 March – A study finds that an optimized globally coordinated marine conservation could be "nearly twice as efficient as uncoordinated, national-level" planning and estimates that bottom trawling releases as much CO2-emissions as pre-COVID-19 aviation.[55][56][57]
NASA reports, based on measurements of over 500 Marsquakes by the InSight lander on the planet Mars, that the core of Mars is between 1,810 and 1,860 km (1,120 and 1,160 mi), about half the size of the core of Earth, and significantly smaller – suggesting a core of lighter elements – than thought earlier.[60][61]
22 March – Astronomers report, for the first time, that the area producing pulses of a repeating fast radio burst (FRB), particularly FRB 180916, is about 1 kilometre (0.62 miles) in scale, based on studies at extremely short timescales.[63][64]
23 March
News media announces the public release, for the first time, of a comprehensive report of UFO events accumulated by the United States over the years.[65]
COVID-19 pandemic: A study finds that the snapshot mass-testing for COVID-19 of ~80% of Slovakia's population during a weekend at the end of October 2020 was highly efficacious, decreasing observed prevalence by 58% within one week and 70% compared to a hypothetical scenario of no snapshot-mass-testing.[66][67]
26 March – A collision between the asteroid 99942 Apophis and Earth is ruled out, for at least the next hundred years, based on new observations by NASA.[71]
30 March – Scientists report evidence of subglacial sediment stored since 1966 that indicates that Greenland was ice-free and vegetated at least once within the last million years.[79][80]
31 March
The first high-bandwidth, wireless brain-computer interface is demonstrated, with 200 electrodes providing 48 megabits per second (Mbit/s) of neural signals.[81][82]
A study finds that carbon emissions from Bitcoin mining in China – where a majority of the proof-of-work algorithm that generates current economic value is computed, largely fueled by nonrenewable sources – have accelerated rapidly, would soon exceed total annual emissions of European countries like Italy and Spain in 2016 and interfere with climate change mitigation commitments.[90][89]
NOAA reports the largest annual increase in methane emissions since records began, with a rise of 14.7 parts per billion (ppb) in 2020.[97]
A study finds that humans engaged in problem-solving tend to overlook subtractive changes, including those that are critical elements of efficient solutions. This tendency to solve by creating or adding elements is shown to intensify with higher cognitive loads in the case of individuals.[98][99]
Scientists confirm, with new genomic data, that initial European modern humans mixed with Neanderthals with continuity to later people in Eurasia and report that such admixture appears to have been more common than previously thought.[102][103]
8 April – Scientists report rough spectral signatures of 958 molecules that may be involved in the atmospheric production or consumption of phosphine, which could prevent misassignments and, if accuracy is improved, be used in future detections and identifications of molecules on other planets such as Venus.[104][105] On 10 April, a news report informs about a launched NASA-funded mission to design and test robotic balloons for future scientific exploration of Venus.[106] On 19 April scientists who reported the detection of well-established or likely biosignature, monophosphine, on Venus publish a preprint recovering the detection of PH3 in the Venusian atmosphere – which was challenged by critical studies – with the proposed SO2-attribution alternative being inconsistent with the available data.[107]
Scientists present a tool for epigenome editing, CRISPRoff, that can heritably silence the gene expression of "most genes" and allows for reversible modifications.[114][115]
Scientists develop a prototype and design rules for both-sides-contacted siliconsolar cells with conversion efficiencies of 26% and above, Earth's highest for this type of solar cell.[119][120]
COVID-19 pandemic: Scientists report that patients who consistently met scientific guidelines of 150+ min/week exercise or similar physical activity had a smaller risk of hospitalisation and death due to COVID-19, even when considering likely risk factors such as elevated BMI.[126][127]
14 April – Astronomers report that the supermassive black hole M87*, first, and to date, the only black hole to be imaged, will be further studied by many observatories from around the world and present results of simultaneous observations and their subsequent analysis.[128][129]
Biologists report that an estimated 2.5 billion adult Tyrannosaurus rex dinosaurs roamed the Earth over the 2.4 million years of their existence.[140][141]
A study assesses that only 3% of the planet's terrestrial surface is ecologically and faunally "intact", with low human footprint and healthy populations of native animal species.[142][143]
Researchers demonstrate the whitest ever paint formulation, which reflects up to 98.1% of sunlight and could be used in place of air conditioners.[144][145]
Scientists show that a class of warp drives that are slower than light, could control the rate of time within the spaceship and are sourced from positive energy could in principle possibly be constructed based on known physical principles. Furthermore, they provide a new argument "why superluminal warp drive solutions may always violate weak energy conditions" and that the concept proposed in a study published in March (see above) "likely forms a new class of warp drive spacetimes".[154][155]
27 April – Astronomers report the discovery of TOI-1431b, an "ultra-hot Jupiter" with a dayside temperature of ~3,000K (2,700 °C), making it one of the hottest exoplanets found to date.[161][162]
29 April – The first, core module of the Chinese Tiangong space station, Tianhe, is placed in low Earth orbit. It is one of three permanent modules intended to be fully assembled in 2022 for a designed lifespan of 10–15 years, is 16.6 m in size and could host three astronaut scientists.[131]
A study assesses benefits of fast action to reduce methane emissions when compared to slower climate change mitigation of this form.[170] On 6 May a U.N. report assesses benefits and costs of rapidly mitigating methane emissions.[171]
Researchers find that China's CO2 emissions surpassed that of all OECD countries combined for the first time in 2019.[174][175][176] On 20 May China's CO2 emissions are found to be 9% higher than pre-COVID-19-pandemic levels in 2021-Q1 with CO2 emissions from fossil fuels and cement production having grown by 14.5% compared to 2020.[174][177][178]
A new record for the smallest single-chip system is achieved, occupying a total volume of less than 0.1 mm3.[192][193]
Scientists estimate, with higher resolution data, that land-use change has affected 17% of land in 1960–2019, or when considering multiple change events 32%, "around four times" previous estimates and investigate its drivers.[194][195]
Scientists report that degrowth scenarios, where economic output either "declines" or declines in terms of contemporary economic metrics such as current GDP, have been neglected in considerations of 1.5 °C scenarios reported by the IPCC, finding that investigated degrowth scenarios "minimize many key risks for feasibility and sustainability compared to technology-driven pathways" with a core problem of such being feasibility in the context of contemporary political decision-making and rebound- and relocation-effects.[198][199][200]
The first use of a brain-computer interface to decode neural signals for handwriting is demonstrated and shows a character output speed of more than double the previous record.[202][203]
Archivists initiate a rescue mission to secure enduring access to humanity's largest public library of scientific articles, Sci-Hub, due to the site's increased legal troubles, using Web and BitTorrent technologies.[205]
20 May – A new record high resolution for atomic imaging is reported, with instrumental blurring reduced to less than 20 picometres.[211][212]
21 May – A study finds that papers in leading journals with findings that can't be replicated tend to be cited more than reproducible science. Results that are published unreproducibly are more likely to be wrong, may slow progress and, according to an author, "a simple way to check how often studies have been repeated, and whether or not the original findings are confirmed" is needed.[213][214][215]
Scientists at Japan's RIKEN institute demonstrate a "dry transfer technique" enabling the precise positioning of optical-quality carbon nanotubes, without the need for a solvent.[218][219]
Scientists elaborate mechanics of memory consolidation during sleep which may allow purposely enabling or strengthening this reactivation of experiences and information.[223][224]
27 May – The U.S. Department of Energy launches Perlmutter, a next-generation supercomputer with four exaflops of AI performance, the world's fastest when measured by 16-bit and 32-bit mixed-precision math.[227]
28 May
Biologists report the development of a new updated classification system for cell nuclei and find a way of transmuting one cell type into that of another.[228][229]
China's EAST tokamak sets a new world record for superheated plasma, sustaining a temperature of 120 million °C for 101 seconds and a peak of 160 million °C for 20 seconds.[230]
29 May – Medical scientists in Vietnam report a new, more contagious, form of the COVID-19 virus, that may be a mixture of the variants first detected in India and Britain.[231]
A new study provides experimental evidence of asymmetric response of interfacial water to applied electric field by using a single layer graphene electrode and a novel surface-sensitive non-linear spectroscopy technique with implications for various water-related processes such as in water purification.[235][236][237]
Scientists report that COVID-19 caused substantial changes to blood cells, sometimes persisting for months after hospital discharge, with implications for COVID-19 diagnostics and treatment.[238][239]
3 June – Scientists report that due to decreases in power generation efficiency of wind farms downwind of offshore wind farms, cross-national limits and potentials for optimization need to be considered in strategicdecision-making.[240][241]
Researchers from Google report a machine learning approach for microchip floorplanning that can outperform human designers.[253][254]
Researchers report the development of quantum nonlinear light microscopy with higher sensitivity and beyond the biological photodamage limit.[255][256]
Researchers report the development of the first quantum brain scanner which uses magnetic imaging and could become a novel whole-brain scanning approach.[262][263]
11 June – Biologists report that DNA polymerases, long thought to only transcribe DNA into DNA or RNA, can also write RNA segments into DNA. Polθ was found to promote RNA-templated DNA repair, with large implications for many fields of biology.[266][265]
14 June – Astronomers describe the largest known spinning structures in the Universe, consisting of "tendrils" of galaxies spanning hundreds of millions of light-years in length.[267][268][269]
Scientists complement extensive evidence that cosmetics are widely designed with formulations and disposals that are known to be harmful to human health and ecosystems, often containing PFAS.[273][270]
18 June – The existence of a "pulse" in Earth's geological activity, occurring approximately every 27.5 million years, is reported. The next pulse is due in about 20.5 million years.[279][280]
19 June – A previously unknown comet, 2014 UN271, is reported by astronomers at the Dark Energy Survey. The object is estimated at between 100 and 200 km in size, potentially making it the largest comet ever discovered, and will pass as close as Saturn in January 2031.[281]
24 June – Astronomers provide a new calculation for when the first stars formed, placing this event between 250 and 350 million years after the Big Bang.[286][287]
Scientists report that natural immunity to COVID-19 via forms of prior infection combined with vaccination synergizes to extraordinarily large immune responses.[292][293]
A study concludes that public services are associated with higher human need satisfaction and lower energy requirements while contemporary forms of economic growth are linked with the opposite. Authors find that the contemporary economic system is structurally misaligned with goals of sustainable development and that to date no nation can provide decent living standards at sustainable levels of energy and resource use. They provide analysis about factors in social provisioning and assess that improving beneficial provisioning-factors and -infrastructure would allow for sustainable forms of sufficient need satisfaction.[303][304]
The smallest and most massive white dwarf ever seen is reported. The star, named ZTF J1901+1458, has a diameter of just 4,300 km but is 1.35 times the mass of the Sun.[307][308]
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.[312][313]
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.[314][315]
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.[316][317]
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.[326][327]
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.[330][331]
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",[333][332] 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.[334][335][332]
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.[336][337]
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.[342][343]
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.[348][349]
A study concludes only 1.5-7 % of "regions"[clarification needed] 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.[352][353]
A study using whole-genome resequencing indicates that Cannabissativa 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.[354][355]
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 Androidsmartphones 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.[356]
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.[358]
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.[361][362]
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.[357]
Scientists report to have created the first complete neuron-level-resolution 3D map of a monkey brain which they scanned within 100 hours.[376][377]
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.[378][379]
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.[389]
August
2 August – Engineers report the development of a prototype wave energy converter that is twice as efficient as similar existing experimental technologies, which could be a major step towards practical viability of tapping into the sustainable energy source.[390][391]
4 August
Scientists identify genetic determinants of ovarian ageing and possible effects of extending fertility in women.[392][393]
Scientists describe the molecular mechanisms by which insectolfactory systems are sensitive enough to recognize and discriminate a vast number of molecules with very few smell receptors.[394][395]
8 August – The National Ignition Facility achieves a 70% yield, compared to the laser energy required to sustain fusion, from inertial confinementfusion energy, an 8X improvement over previous experiments in spring 2021 and a 25X increase over the yields achieved in 2018.[402]
A study based on OSIRIS-REx data concludes there to be a 1:1750 chance of an impact of asteroid (101955) Bennu by 2300, with the highest chance of impact being in 2182.[414][415]
22 August – Astronomers conclude in a preprint that – controversially due to there being only few data points – there is high confidence "Planet 9" exists, that it likely has a mass of ~6.2 Earths and is closer than thought previously and report its likely orbit.[436][437]
24 August
Cerebras announces a new hardware and software platform that can support AI models of 120 trillion parameters, enabling neural networks greater than the equivalent number of human brainsynapses.[438]
27 August – Scientists report about vaccine effectiveness, pandemic severity impacts and regional prevalence of SARS-CoV-2 Delta variant overall and its newly subdivided subvariants named from AY.1 onwards,[443] the first two of which were differentiated like so – also termed "Delta Plus" – in June.[444] On 10 August a preprint reports a case of asymptomatic transmissions associated with high viral load among vaccinated patients infected by AY.3.[445]
28 August – The world's northernmost island, a small patch of land measuring 60 x 30 metres, is reported by scientists off the coast of Greenland. The name Qeqertaq Avannarleq is proposed, which means "the northernmost island" in Greenlandic.[446]
Observation of a new class of supernova triggered by a black hole or neutron star crashing into the core of a companion star is reported by astronomers, based on studies of an extremely luminous source of radio waves called VT 1210+4956.[461][462][463]
A study finds that outdoor air pollution is associated with substantially increased mortality "even at low pollution levels below the current European and North American standards and WHO guideline values".[467][468] On 22 September, for the first time since 2005, the World Health Organization (WHO), after a systematic review of the accumulated evidence, adjusted their air quality guidelines whose adherence could save millions of lives, protect against future diseases and help meet climate goals.[469][470]
6 September – Experts report that one-third of all chondrichthyes fish species are threatened with extinction, mainly caused by overfishing.[481][482]
8 September
Cysteamine, an antioxidant drug already approved for human use, is shown to reverse atherosclerosis, the process responsible for heart attacks and strokes, in mice.[483][484]
Scientists provide the first scientific assessment of the minimum amount of fossil fuels that would need to be securedfrom extraction per region as well as globally, to allow for a 50% probability of limiting global warming by 2050 to 1.5 °C.[485][486]
Scientists report that Earth is reflecting less light – a dimming of ~0.5% in reflectance over two decades may have both been co-caused by climate change as well as substantially increase global warming.[487][488]
10 September
Scientists report what could be the discovery of the oldest rock art, likely dating back to ~169–226,000 years ago, much older than what was previously thought to be the earliest known drawing, made ~73,000[489] years ago. Children likely intentionally placed a series of hands and feet in mud. The findings could also be the earliest evidence of Hominins on the above 4000 m a.s.l. high Tibetan plateau.[490][491][492]
43 expert scientists publish the first scientific framework version that – via integration, review, clarifications and standardization – enables the evaluation of levels of protection of marine protected areas and can serve as a guide for improving, planning and monitoring marine protection-quality and -extents such as in efforts towards the 30%-protection-goal of the "Global Deal For Nature"[493] and the UN's SDG 14.[494][495]
The CDC reports that despite prevalence of the Delta variant people vaccinated against COVID-19 are ~11 times less likely to die from COVID-19 (age-standardized rates of 1.6 versus 0.1 and 1.1 versus 0.1 weekly deaths per 100,000 U.S. citizens), showing vaccines' effectiveness at preventing severe disease.[496][497]
13 September – A scientific review concludes that accumulating data suggests dietary restriction (DR) – mainly intermittent fasting and caloric restriction – results in many of the same beneficial changes in adult humans as in studied organisms, potentially increasing health- and lifespan.[498][499] A review published on 22 September provides an overview of DR as an intervention and develops a framework for a proposed field of "precision nutrigeroscience".[500][501] A study published on 29 September identifies circadian-regulatedautophagy as a critical contributor to intermittent time-restricted fasting-mediated lifespan extension in Drosophila and suggests that only certain forms of and/or combinations with intermittent fasting – intervals during which no food but only e.g. water and tea/coffee are ingested[502] – may be effective beyond the benefits of healthy body weight.[503][504]
Scientists confirm that widespread phytoplankton blooms can be a feedback effect of wildfires. The climate change-exacerbated 2019–2020 Australian wildfires caused oceanic deposition of wildfire aerosols, enhancing marine productivity and thereby increased oceanic carbon dioxide uptake.[508][509] A study using satellite data complements these findings, constraining the amount of CO2 emissions of the fires from November 2019 to January 2020 to around 715 million tons.[510][511]
Media outlets report that the world's first cultured coffee products have been created by two biotechnology companies, still awaiting regulatory approval for near-term commercialization.[512][513] Such products, for which multiple companies' R&D have acquired substantial funding, may have equal or highly similar effects, composition and taste as natural products but use less water, generate less carbon emissions, require less labor[additional citation(s) needed] and cause no deforestation.[512]
16 September – Scientists report evidence of clothes being made 120,000 years ago based on findings in deposits in Morocco, a country in the northwestern part of Africa.[514][515]
Researchers report in a preprint the discovery of i.a. the so far closest known relative virus, with a 96.8% similarity, to SARS-CoV-2 in samples from wild horseshoe bats in northern Laos – 0.7% more similar than the virus RaTG13 discovered in China in 2013. Their findings indicate that, as of 2021, SARS-CoV-2-like viruses potentially infectious for humans circulate in bats in the Indochinese peninsula and that the pandemic virus may not originate from Wuhan.[518][519] Other scientists complement these findings, reporting in a preprint published on 20 September, that they could not find any SARS-CoV-2 related viruses in any samples collected in China, including from the only two domestic caves where RaTG13 and RmYN02 were detected, indicating such viruses may currently not circulate in bats in the country.[518][520]
22 September – Astronomers report the discovery of a nearby spherical structure, a 'superbubble', on the edges of which giant molecular clouds (Perseus and Taurus) with regions of star formation are being formed, the Per-Tau Shell.[521][522]
Researchers report the world's first artificial synthesis of starch. The material essential for many products and the most common carbohydrate in human diets was made from CO2 in a cell-free process and could reduce land, pesticide and water use as well as greenhouse gas emissions while increasing food security.[525][526]
Media outlets report that in Japan the first CRISPR-edited food has gone on public sale. Tomatoes were genetically modified for around five times the normal amount of possibly calming[532]GABA.[533] CRISPR was first applied in tomatoes in 2014.[534]
26 September – Researchers estimate that children born in 2020 (e.g. "Generation Alpha") will experience 2–7 times as many extreme weather events, particularly heat waves, compared to people born in 1960 (e.g. "Baby Boomers" and "Generation X") under current climate policy pledges over their lifetimes, raising issues of intergenerational equity.[537][538]
Pathogen researchers report the development of machine learning models for genome-based early detection and prioritization of high-risk potential zoonotic viruses in animals prior to spillover to humans. They conclude that their tool could be used for virus surveillance for pandemic prevention via (i.a.) measures of "early investigation and outbreak preparedness" and would have been capable of predicting SARS-CoV-2 as a high-risk strain.[545][546]
October
1 October – A company conducting a preliminary small (~380 patients × 2) clinical trial launched a year ago[547] reports that molnupiravir substantially reduced the risk of hospitalization (7.3% to 14.1%) and death (8 to 0) from COVID-19.[548][549]
Metascientists report, based on a citation analysis, that "structures fostering disruptive scholarship and focusing attention on novel ideas" could be important as in a growing scientific fieldcitation flows disproportionately consolidate to citing already well-cited papers, possibly slowing and inhibiting canonical progress.[551][552]
The 2021 Nobel Prize in Chemistry is awarded to Benjamin List and David W.C. MacMillan for their work in creating a tool to build molecules, that may be useful for studies on developing new drugs and reducing the effect of chemicals on the environment.[554]
A study of data traffic by popular smartphones running variants of the Android software finds substantial by-default data collection and sharing with no opt-out and implications for users' privacy, control and security.[556][557]
8 October – A new eco-friendly way of extracting and separatingrare earth elements is described, using a bacteria-derived protein called lanmodulin, which binds easily to the metals.[564][565]
11 October
Scientists report more precise dating of what appear to be the earliest bipedal footprints with hominin-like characteristics, the Trachilos footprints. They are found to be ~6.05 million years old, which is around the time of Orrorin – the previously earliest theorized species of Homininae[566] until these footprints were controversially dated in 2017,[567] despite being discovered outside of Africa in Crete, Greece. However, these apes are not necessarily associated with human evolution.[568][569][570]
The pilot project of the "world's first automated, driverless train" is launched in the city of Hamburg, Germany. The conventional, standard-track, non-metro train technology could theoretically be implemented for rail transport worldwide and is reported to also be substantially more energy efficient.[571][572]
Scientists project public health impacts, along with some of the environmental damage, of a, simulated, imminent Red Sea oil spill from the FSO Safer.[573][574]
Astronomers report the first evidence of a giant impact between two exoplanets, which occurred in the HD 172555 system, based on analysis of gas and dust concentrations.[589][590]
Scientists report that, according to their analysis, today's domestichorses descend from the lower Volga-Don region, Russia. 273 ancient horse genomes further indicate that these populations replaced almost all local populations as they expanded rapidly throughout Eurasia from about 4200 years ago, that certain adaptations were strongly selected for by horse riding, and that equestrian material culture – including Sintashta spoke-wheeled chariots and in the case of Asia Indo-Iranian languages – spread alongside.[591][592]
Medical researchers announce that on 25 September the first successful xenotransplantation of a genetically engineered pig kidney, along with the pig thymus gland to make the immune system recognize it as part of the body, to a brain-dead human with no immediate signs of rejection, moving the practice closer to clinical trials with living humans.[595][596]
Astronomers report, with two studies, that 'BLC1' does not appear to be a technosignature or extraterrestrial radio transmission because 15 similar observations were made between 2019 and 2020 that did not originate from around Proxima Centauri – and hence are likely results of forms of local radiofrequency interference – and propose a sequence of "verification checks for narrowband technosignature signals".[605][606][607]
Another, clearer case of quantum advantage with Zuchongzhi is reported.[608][609][610] A third study reported that Zuchongzhi 2.1 completed a task of classically simulating random circuit sampling that "is about 6 orders of magnitude more difficult than that of Sycamore".[611]
Astronomers report that the orbits of the detected exoplanets hosted by the star HD 3167 are unusual: two planets (HD 3167 c; HD 3167 d) revolve around the poles of the star, whereas the third planet (HD 3167 b) orbits around the equator of the star instead.[614][615]
Researchers release a "policy sequencing" framework, in particular for policies of polycentric governance for completely halting and preventing deforestation based on data about already implemented government-designed policies, UN-decidedREDD+ initiatives and voluntary private sector initiatives of recent deforestation interventions.[616][617]
One year after India and South Africa called on WTO to temporarily waive TRIPS vaccine patents for accelerated deployment of COVID-19 vaccines around the world, the WTO reportedly fails to find an accord for doing so.[625] No mechanisms of alternative medical research and development incentive-systems[626] or technical details of proposed "sharing" after certain amounts of profit[627] were reported and some argue that, instead of intellectual property rights, manufacturing know-how is the main barrier to expanding capacity.[626]
Scientists discover that up to about 20,000 metric tons of microplastics may be stored in coral skeletons worldwide every year, marking the first time that a living microplastic "sink", or long-term storage site, has been quantified.[628][629]
2 November – A study concludes that PM2.5air pollution induced by contemporary forms of free trade and consumption by the 19 G20 nations (the EU as a whole is not included) causes two million premature deaths annually, suggesting that the average lifetime consumption of about ~28 people in these countries causes at least one premature death (average age ~67) while developing countries "cannot be expected" to implement or be able to implement countermeasures without external support or internationally coordinated efforts.[635][634]
3 November
Astronomers using the ALMA report the presence of water in SPT0311-58, a galaxy nearly 12.9 billion light-years from Earth. This is the most distant detection of a required element for life in a regular star-forming galaxy.[636][637]
Scientists report that large shares of wild deer in the U.S. have been infected with SARS-CoV-2. The test results showed one "mismatch" for 2019, low inhibition values in 2020 and 152 positive samples (40%) in 2021.[638] A preprint published on 1 November found that ~80% of samples between late November 2020 and January were positive.[639][640] Such spillovers may cause reservoirs for mutating variants that spill back to humans – a possible source for variants of concern other than immunocompromised people.[639]
A review outlines research and data about COVID-19 vaccinations for children – recommended in the U.S. a day previously (for 5–11 years olds) by the CDC[641] – including about populations-levels factors.[642]
A study contributes to a disentangling of the current geopolitical and economic implications of and incentives for a swift renewable energy transition, suggesting i.a. that how fast fossil energy markets decline is primarily decided by the major energy importers China, India, Japan and the EU and that transition dynamics may reverse the free-rider problem in the case of energy sectors, specifically from strategic national standpoints which are not short-term.[645][646]
Researchers demonstrate a novel X-ray imaging technique, "HiP-CT", for 3D cellular-resolution scans of whole organs, using the ESRF's EBF. The published online Human Organ Atlas includes the lungs from a donor who died with COVID-19.[647][648][649]
5 November – A company reports that a phase 2/3 clinical trial shows that Paxlovid can reduce COVID-19 hospitalizations of high-risk adults by 89% when given within three days after symptom onset.[650][651]
8 November – Scientists prove that the brain (the insular cortex of mice/mammals) also "remembers" immune activity against past infections, with reactivation – or stimulation – of the neurons being able to cause – or shape – the inflammatory immune response.[652][653]
9 November
Astrophysicists report the discovery of unexplained blockage of high-energy cosmic rays entering the Galactic Center, such as a strong magnetic field.[654][655]
Astronomers using the Very Large Telescope report the discovery of a black hole in NGC 1850 by viewing its influence on the motion of a star in close proximity, the first direct dynamical detection of a black hole in a young massive cluster.[661][662]
The first-ever simulation of baryons on a quantum computer is reported by a university.[663][664]
Astronomers identify a long filament of cold, dense gas connecting two of the Milky Way's spiral arms, the first known observation of such a galactic structure in the Milky Way.[665]
Bionanoengineers report a novel therapy for spinal cord injury – an injectable gel of nanofibers that contain moving molecules that cause cellular signaling and mimic the matrix around cells in mice.[666][667][668]
A study investigates how tidal energy could be best integrated into the Orkneyenergy system.[669] On 3 November, a review assesses the potential of tidal energy in the UK's energy systems, finding that it could, according to their considerations that include economic cost-benefit analysis, deliver 34 TWh/y or 11% of its energy demand.[670][671]
14 November – A time-allocation study estimates that in 2020 over 130 million hours of researchers' time were spent on peer review.[672][673]
Scientists report a large extent of alternative splicing – cases of a single gene (a template) being used to create instructions (mRNAs) for building different proteins – in the mouse and human cortex and release the transcriptomes on a public database.[678][679]
A tech company reveals a new 127 quantum bit processor named 'IBM Eagle', which is the most powerful quantum processor ever made.[680][681]
The largest public dataset of whole genomes is made available through a Web platform. The entire genomes of 200,000 UK Biobank participants, linked to anonymized medical information, are made more accessible for biomedical research than prior, less comprehensive datasets.[687][688]
Scientists call for the creation of space biosecurity measures and inform the creation of planetary protection policies that aim to prevent forward contamination of extraterrestrial bodies as well as backward contamination.[689][690]
Scientists report the development of a vaccine of mRNAs for the body build 19 proteins in tick saliva which, by enabling quick development of erythema (itchy redness) at the bite site, protects guinea pigs against Lyme disease from ticks.[691][692]
21 November – Sri Lanka announces that it will lift its import ban on pesticides and herbicides, explained by both a lack of sudden changes to widely applied practices or education systems and contemporary economics and, by extension, food security, protests and high food costs. The effort to become the world's first completely organic farming nation was challenged by effects of the COVID-19 pandemic.[696][697]
22 November
Scientists detect a quantum effect that blocks atoms from scattering light.[698]
A study using data on ~30,000 patients, for the first time, indicates that aspirin may be associated with an increased (26%) risk for heart failure in persons with at least one cardiovascular risk factor.[699][700] An author notes that the findings require confirmation and the link with heart failure to be clarified.[701]
25 November – Researchers systematically assess impacts of climate change mitigation options on 18 constituents of well-being, finding largely beneficial effects of demand-side solutions based on inputs from 604 studies.[703][704]
26 November – The WHO announces the classification of the Omicron variant as a SARS-CoV-2 variant of concern. The variant, that became dominant (74% of samples) in South Africa in November, was detected by the NGS-SA genomic surveillance on 8 November[705][706] and reported to the WHO on 24 November.[682] It has a large number of mutations that, according to early preliminary evidence, appear to increase risk of reinfection,[682] may increase transmissibility compared to Delta and may affect vaccines' efficacies with a key question being whether it causes less severe prognoses.[707][708]
29 November – A team of scientists reports a new form of biological reproduction in xenobots that are made up of and are emersed in frog cells.[709][710]
December
1 December
Scientists discover the footprint of an ancient hominid that lived alongside Lucy.[711][712]
3 December – Scientists demonstrate that grown brain cells integrated into digital systems can carry out goal-directed tasks with performance-scores. In particular, playing a simulated (via electrophysiological stimulation) Pong which the cells learned to play faster than known machine intelligence systems, albeit to a lower skill-level than both AI and humans. Moreover, the study suggests it provides first empirical evidence of information-processing capacity differences between neurons from different species.[718][719]
A study suggests that when two people wear surgical masks, while the infectious one is speaking, the risk of COVID-19 infection at a distance of 1.5 m remains below 30% after one hour, but when both wear a well-fitting FFP2mask, it is 0.4%.[728]
Researchers investigating sources of urban PAHsair pollution in Athens report that wood-burning could be causing a third (31%) of such urban air pollution, like diesel and oil combined or gasoline, and, especially during winter days, is responsible for nearly half of PAH cancer-risk.[729][730]
A study suggests that mutations that promote breakthrough infections or antibody-resistance could be a new mechanism for viral evolution success of SARS-CoV-2 and that such may become a dominating mechanism of its evolution.[731] On 27 December, a preprint finds that "the rapid spread of the Omicron VOC primarily can be ascribed to the immune evasiveness rather than an inherent increase in the basic transmissibility".[732][733] Studies also showed the variant to escape the majority of existing SARS-CoV-2 neutralizing antibodies, including of sera from vaccinated and convalescent individuals.[734][735][736][737]
A scientific review summarizes research and data about telemedicine. Its results indicate that, in general, outcomes of such ICT-use are as good as in-person care with health care use staying similar.[738][739]
Researchers report the development of face masks that glow under ultraviolet light if they contain SARS-CoV-2 when the filter is taken out and sprayed with a fluorescent dye that contains antibodies from ostrich eggs.[742]
Studies, some of which using large nationwide datasets from either Israel and Denmark, find that vaccine effectiveness of multiple common two-dosed COVID-19 vaccines is substantially lower against the SARS-CoV-2 Omicron variant than for other common variants including the Delta variant, and that a new (often a third) dose – a booster dose – is needed and effective, with it i.a. substantially reducing deaths from the disease compared to cohorts who received two doses.[743][744][745][746][747][748]
Applied behavioural scientists demonstrate a novel type of intervention studies, a "megastudy", and investigate the efficacy of 54 different designed by separate teams interventions to increase weekly gym-visits of ~60,000 members of a fitness chain, such as digital feedback in the form of redeemable points that are rewarded for returning to the gym after a missed workout.[749][750]
The Log4Shellsecurity vulnerability in a Java logging framework is publicly disclosed two weeks after its discovery. Because of the ubiquity of the affected software, experts have described it as a most serious computer vulnerability.[752] In a high-level meeting, the importance of security maintenance of open-source software – often also carried out largely by few volunteers – to national security was clarified.[753][754]
A study reviews modern analytic procedures, including mass spectrometry techniques, for characterization, analysis, and identification of unknown materials and how such were applied to study materials that, according to witnesses, dropped from hovering unknown aerial objects (or UFOs). It suggests that the full range of current capabilities of materials analysis have not been applied so far and, after reviewing a range of proposed explanations, that these materials' purposes and characteristics, such as their isotope ratios,[755] are very odd and remain unexplained.[756]
Scientists report the development of a genome editing system, called "twin prime editing", which surpasses the original prime editing system reported in 2019 in that it allows editing large sequences of DNA, addressing the method's key drawback.[757][758]
Scientists studying the huge Thwaites Glacier in West Antarctica report evidence that it could "shatter like a car windscreen" within five to ten years, potentially adding 65 cm to global sea levels in the long term.[765]
Researchers report the development of a database and analysis tool about perovskite solar cells which systematically integrates over 15,000 publications, in particular data about over 42,400 photovoltaic devices.[768][769]
Scientists call for accelerated efforts in the development of broadly protective vaccines, especially a universal coronavirus vaccine that durably protects not just against all SARS-CoV-2 variants but also other coronaviruses, including already identified animal coronaviruses with pandemic potential.[773]
Researchers report the development of perovskite solar cells based on self-constructed high-throughput screening of mixtures and contact layers, that – based on the stability tests – are estimated to last for over two years under normal circumstances.[779][780]
22 December – Japanese scientists announce a key step in the development of a quantum computer using photons, which eliminates the need for an ultracold environment used to cool existing machines.[787][788]
24 December – A study suggests that, based on the strength of positive selection pressure, the molecular spectrum of mutations and known mutations for adaptation to mouse hosts, the SARS-CoV-2 Omicron variant may have evolved in mice and then spilled back to humans.[791][792]
28 December – Scientists report that production of ammonia in the clouds of Venus, possibly by life, may make the environment less acidic and suitable for life, with the atmospheric model matching observations better than earlier ones.[798][799]
30 December
China's EAST tokamak sustains 120 million °C plasma for 17 minutes (1,056 seconds) for the development of fusion energy (which requires i.a. temperatures over 150 million °C).[800][801]
[clarification needed]The first CRISPR-gene-edited marine animals/seafood and second set of CRISPR-edited food has gone on public sale in Japan: two fish of which one species grows to twice the size of natural specimens due to disruption of leptin, which controls appetite, and the other grows to 1.2 the natural size with the same amount of food due to disabled myostatin, which inhibits muscle growth.[804][805]
Engineering first light of the Vera C. Rubin Observatory's camera was anticipated for 2021 with full science operations to begin a year later.[806][807][808] Delayed to October 2022[809] and later to February 2023[810] due to the COVID-19 pandemic.
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