2021 in science

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A number of significant scientific events have occurred or are scheduled to occur in 2021.

Events

January

January 2021 in science

Science Summary for this section (January) 1 January – Beginning of the implementation of Plan S, an initiative for open-access science publishing launched in 2018 that requires papers from 2021 onwards from over 10 European countries that resulted from research funded by public grants to be published under an open licence in compliant journals or platforms, available to all. 4 January Media reports that engineers worldwide discuss a negative leap second and other possible measures as Earth spun faster in 2020. Researchers describe how the damage to nerve cells caused by motor neurone disease could be repaired by improving the energy levels in mitochondria. Scientists describe a CRISPR-Cas9 genome editing approach which could be used to treat wet age-related macular degeneration caused by VEGFA and Herpes simplex type 1: injection of engineered lentiviruses into the affected anatomical regions for transient editing without inducing off-target edits. 5 January – Using theoretical calculations, researchers suggest that humans would be unable to control a superintelligent AI. 6 January: The first systematic review of the scientific evidence around global waste, its management and its impact on human health and life is published. 6 January Scientists report the successful use of gene editing in mice with progeria, a premature aging disease. Chinese researchers report that they have built the world's largest integrated quantum communication network, combining over 700 optical fibers with two QKD-ground-to-satellite links for a total distance between nodes of the network of networks of up to ~4,600 km. The first systematic review of the scientific evidence around global waste, its management and its impact on human health and life is published, providing assessments, suggestions for corrective action, engineering solutions and requests for further research. It finds that about half of all the municipal solid terrestrial waste – or close to one billion tons per year – is either not collected or mismanaged after collection, often being burned in open and uncontrolled fires. Authors conclude that "massive risk mitigation can be delivered" while noting that broad priority areas each lack a "high-quality research base", partly due to the absence of "substantial research funding", which scientists often require. 7 January A potential mRNA vaccine for multiple sclerosis is presented by a collaboration including BioNTech, with a study in mice showing great promise for improving symptoms and stopping disease progression. The Distribution and Frequency of P681H and D614G Mutations Among All SARS-CoV-2 Sequences by Month Reported in the GISAID Database in Year 2020 Time-series representations of mean relative body size Scientists conclude that environmental factors played a major role in the evolution of the slowly-evolving, currently low-diverse Crocodilia (and their ancestor-relatives), with warmer climate being associated with high evolutionary rates and large body sizes. 8 January News outlets report that scientists, with the Juno spacecraft orbiting Jupiter, detected an FM radio signal from the moon Ganymede which is reportedly caused by cyclotron maser instability and similar to both WiFi-signals and Jupiter's radio emissions. A study about the radio emissions was published in September 2020 but did not describe them to be of FM nature or similar to WiFi signals. Artist's conception of the quasar J0313–1806, seen as it was only 670 million years after the Big Bang Scientists report the discovery of the most distant, and therefore oldest, quasar, J0313–1806. It is located 13 bn light-years away, does not yet have an accepted non-identifier name and significantly challenges theoretical models of early SMBH growth, apparently existing just ~670 million years after the Big Bang despite its large size. Archaeologists report that the African cultural phase, called Middle Stone Age, thought to have lasted from ~300–30 ka, lasted to ~11 ka in some places, highlighting significant spatial and temporal cultural variability. WASP-62b is confirmed to be the first hot Jupiter exoplanet without clouds or haze in its observable atmosphere. 12 January Scientists report the use of CRISPR/Cas9 genome editing to produce a tenfold increase in super-bug targeting formicamycin antibiotics. COVID-19 pandemic: The National Institute of Infectious Diseases of Japan reports the detection of significant variant of SARS-CoV-2 Lineage P.1 via testing of travelers from Brazil, which was later reported to originate from widespread circulation in Brazil. Larger populations promote category convergence across populations Researchers report that large populations consistently converge on highly similar category systems, relevant to lexical aspects of large communication networks and cultures. 13 January: A group of 17 high-ranking ecologists conclude that current challenges – themselves individually – that humanity faces and which may lead to a "ghastly" future are large and underestimated. 13 January A new record high temperature of the world's oceans is reported, measured from the surface level down to a depth of 2,000 metres. In Lyon, France, the first transplant of both arms and shoulders is performed on an Icelandic patient. Astrophysicists report that energy extraction – with high efficiency – from rotating black holes with a high spin via reconnection of magnetic field lines of an externally supplied magnetic field that accelerates escaping plasma particles is possible. Advanced civilizations may be capable of doing so. Scientists report that all glacial periods of ice ages over the last 1.5 M years were associated with northward shifts of melting Antarctic icebergs which changed ocean circulation patterns, leading to more CO2 being pulled out of the atmosphere. Authors note that this process may be disrupted as the Southern Ocean may be too warm for the icebergs to travel far enough to trigger these changes or effects. A group of 17 high-ranking ecologists publish a perspective piece that reviews a number of studies that, based on current trends, indicate that future environmental conditions will be far more dangerous than currently believed, concluding that current challenges – themselves in specific – that humanity faces are large and underestimated. The small group cautions that such an "optimism bias" is prevalent and that fundamental changes are required, listing a few of such they consider adequate in the form of broad descriptions in their largely static document, published by a scientific journal. 15 January Researchers in China report the successful transmission of entangled photons between drones, used as nodes for the development of mobile quantum networks or flexible network extensions, marking the first work in which entangled particles were sent between two moving devices. Scientists from U.S. federal medical agencies report that gut infections increase its microbiota's resistance to subsequent infections and that this is associated with taurine, whose exogenous supply can induce this microbiota alteration. 17 January – LauncherOne becomes the first successful all-liquid-fuelled air-launched rocket to reach orbit. 20 January Archaeologists report the discovery of what may be earliest evidence of human use of symbols – a ~120-ky-old bone engraved with six lines. Researchers report that myeloid cells are drivers of a maladaptive inflammation element of brain-ageing in mice and that this can be reversed or prevented via inhibition of their EP2 signalling. Scientists report that the MOTS-c peptide in the mitochondrial genome is an AMPK-related regulator of age-dependent physical decline in mice and that its exogenous supply initiated in late-life can substantially increase their physical performance and healthspans. 22 January A study described as the "first long-term assessment of global bee decline", which analyzed GBIF-data of over a century, finds that the number of bee species declined steeply after the 1990s, shrinking by a quarter in 2006–2015 compared to before 1990. COVID-19 pandemic: Preliminary analyses indicate that the SARS-CoV-2 variant of concern detected in the U.K. is associated with an increased severity of disease. 25 January: Global ice loss is found to be accelerating at a record rate in a scientific review, matching the worst-case scenarios of the IPCC. 25 January Global ice loss is found to be accelerating at a record rate in a scientific review, matching the worst-case scenarios of the IPCC. Astronomers report the discovery of TOI-178, a rare system of six exoplanets locked in a complex chain of Laplace orbital resonances and variations in the densities that are hard to explain. Australian scientists develop a new cryogenic computer system called Gooseberry, which has potential for scaling up quantum computers from dozens to thousands of qubits. 26 January – A study suggests that operating air purifiers or air ventilation systems in confined spaces during their occupancy by multiple people leads to increased airborne virus transmission due to air circulation effects. 27 January Researchers report a way to manufacture transparent wood, whose qualities exceed those made with the main process used earlier, that requires substantially less amounts of chemicals and energy – solar-assisted chemical brushing. Scientists report that shark and ray populations have fallen by 71% since 1970 as a result of human actions, primarily overfishing. 28 January COVID-19 pandemic: Medical scientists report the first detection of the SARS-CoV-2 Beta variant. Researchers report the development of a highly efficient single-photon source for quantum IT with a system of gated quantum dots in a tunable microcavity which captures photons released from these excited "artificial atoms".

February

February 2021 in science

Science Summary for this section (February) 2 February 2 February: Effectiveness of Sputnik-V vaccine is shown to be 92%. COVID-19 pandemic: Russia's Sputnik V vaccine is shown to be 92% effective against COVID-19, according to late stage trial results published in The Lancet. COVID-19 pandemic: Medical scientists in the United Kingdom report the detection of E484K (in 11 out of 214,000 samples), a mutation of the U.K. coronavirus variant that may compromise current vaccine effectiveness. Astronomers report that Tabby's Star, observed to dim in very unusual ways, has been found to be a binary stellar system. 5 February COVID-19 pandemic: A study suggests that climate change may have driven the emergence of SARS-CoV-2, by increasing the growth of forest habitats favoured by bats carrying the virus. A new theory aims to explain ʻOumuamua's peculiarities naturally and estimates, if true, ~4% of astronomical bodies in the interstellar medium to be N2 ice fragments. A study identifies genes for face shape and, for the first time, finds that a version of a gene – which was possibly selected for due to adaption to cold climate via fat distribution – is associated with a facial feature, lip thickness, and introgressed from ancient humans – Denisovans – into modern humans, Native Americans. Researchers demonstrate a first prototype of quantum-logic gates for distributed quantum computers. 8 February – Scientists report an updated status of studies considering the possible detection of lifeforms on Venus (via of phosphine) and Mars (via methane). 9 February The UAE's Hope spacecraft becomes the first Arabian mission to successfully enter orbit around Mars. A study using a high spatial resolution model and an updated concentration-response function finds that 10.2 million global excess deaths in 2012 and 8.7 million in 2018 – or a fifth – were due to air pollution generated by fossil fuel combustion, significantly higher than earlier estimates and with spatially subdivided mortality impacts. 9 February: Updated probabilistic forecast of CO2 emissions, based on data to 2015 and the method of Raftery et al. A study concludes that the rates of emissions reductions need to increase by 80% beyond NDCs to meet the 2 °C upper target range of the Paris Agreement, that the probabilities of major emitters meeting their NDCs without such an increase is very low, estimating that with current trends the probability of staying below 2 °C of warming is 5% and if NDCs were met and continued post-2030 by all signatory systems 26%. A study finds that air pollution by nitrogen dioxide could be a technosignature by which one could detect extraterrestrial civilizations via "atmospheric SETI". 10 February The Chinese Tianwen-1 spacecraft successfully enters orbit around Mars. A journal-accepted preprint suggests observational data for a planet-mass object "Planet 9" at the outer Solar system is not significant and could be selection bias. Scientists deduce in a review that Homo sapiens does not have a single origin in terms of ancestor birthplaces being limited to a small geographic region and that current knowledge about long, continuous and complex – e.g. often non-singular, parallel, nonsimultaneous and/or gradual – emergences of characteristics is consistent with a range of evolutionary histories. Researchers report the development of a wearable thermoelectric generator with characteristics that make it a candidate for devices continuously harvesting body-heat energy and solar energy with applications such as powering wearable electronics. 18 February: NASA's Perseverance rover lands on Mars. 11 February The core of globular cluster NGC 6397 is found to contain a dense concentration of compact remnants (white dwarfs, neutron stars and black holes), based on new data from the Hubble Space Telescope and the Gaia astrometric mission. 12 February Researchers report that brain organoids created with stem cells into which they reintroduced the archaic gene variant NOVA1 present in Neanderthals and Denisovans via CRISPR-Cas9 shows that it has a major impact on neurodevelopment and that such genetic mutations during the evolution of the human brain underlie traits that separate modern humans from extinct Homo species. A subsequent study failed to replicate the differences in organoid morphology between the modern human and the archaic NOVA1 variant, consistent with suspected unwanted side effects of CRISPR editing in the original study. 15 February Scientists report that the impactor that led to the demise of the dinosaurs 66 million years ago was a fragment from a disrupted comet, rather than an asteroid which has long been the leading candidate among scientists. Researchers report, for the first time, the detection of lifeforms 872 m below the ice of Antarctica, at a depth of 1,233 m and 260 km from the open water at the Filchner-Ronne Ice Shelf's calving margin. 16 February – Global warming is found to cause increases of pollen season lengths and concentrations. 17 February – Scientists report the first sequencing of DNA from animal remains more than a million years old – in this case of a mammoth. 18 February NASA's Mars 2020 mission (containing the Perseverance rover and Ingenuity helicopter drone) lands on Mars at Jezero Crater, after seven months of travel. Astronomers report that Cygnus X-1, one of the first known black holes in the Milky Way galaxy, is substantially more massive than first thought. This finding challenges the way the evolution of massive stars is understood. Teams of cognitive scientists report having established real-time communication with people undergoing a lucid dream and show that they were able to comprehend questions and use working memory. 19 February Scientists report that the short global geomagnetic reversal – a geomagnetic excursion – of Earth's magnetic field ~42,000 years ago – the Laschamp event – in combination with grand solar minima, caused major extinctions and environmental changes and may have contributed to the extinction of the Neanderthals and appearances of cave art. It altered the geographical extension of auroras and levels of harmful radiation worldwide. They term the event which they find to constitute a major enviro-archaeological boundary "Adams Transitional Geomagnetic Event". Thomas Metzinger, a German philosopher of cognitive science and applied ethics, calls for a "global moratorium on synthetic phenomenology" which, "until 2050", precautionarily bans "all research that directly aims at or knowingly risks the emergence of artificial consciousness on post-biotic carrier systems" – and could be gradually refined. The paper does not describe mechanisms of global enforcement of proposed regulations which do not consider biotic or semi-biotic systems and aims to limit suffering risks. 22 February – Astronomers release, for the first time, a very high-resolution map of 25,000 active supermassive black holes, covering four percent of the Northern celestial hemisphere, based on ultra-low radio wavelengths, as detected by the LOFAR in Europe. 25 February – Researchers confirm that the Atlantic meridional overturning circulation, which includes the Gulf Stream, is at its weakest since about 1,000 years ago, experiencing unprecedented weakening – likely due to global warming – which could result in more extreme weather events – including heatwaves and intense winters – and is moving towards a "tipping point". 26 February – COVID-19 pandemic: The Wall Street Journal reports that a purported patient zero of COVID-19 may have been infected by parents who visited a different food market than the Huanan Seafood Wholesale Market that has been thought to be the primary source of the infection earlier. 28 February – Winchcombe meteorite: Fragments of a carbonaceous chondrite meteorite, the first known in Britain, fall at Winchcombe in the English Cotswolds.

March

March 2021 in science

Science Summary for this section 1 March: A review classifies SETI technosignatures. 1 March A scientific review produced by the i.a. NASA-sponsored online workshop TechnoClimes 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 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. 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. A study published on 31 March finds higher intake of processed meat was associated with "a higher risk of mortality and major CVD". 3 March COVID-19 pandemic: Scientists report that a much more contagious SARS-CoV-2 variant, Lineage P.1, first detected in Japan, and more recently found in Brazil, as well as in several places in the United States, may be associated with COVID-19 disease reinfection after recovery from an earlier COVID-19 infection. Scientists demonstrate a bioinspired self-powered soft robot for deep-sea operation at the deepest part of the ocean at the Mariana Trench. The robot features artificial muscles and wings out of pliable materials and electronics distributed within its silicone body and could be used for exploration and environmental monitoring. Scientists report the discovery of an endosymbiont, bacteria Azoamicus ciliaticola, of an anaerobic ciliate to which it provides energy in the stored form of ATP. Unlike mitochondria, which play the same role in eukaryotes, it enables its host to breathe nitrate instead of oxygen. 4 March – COVID-19 pandemic: Scientists report a problematic COVID-19 variant, less susceptible to vaccines, a combination of British B.1.1.7 and South African E484K (Eeek) mutations, in the state of Oregon. 5 March – NASA names the landing site of the Perseverance rover in Jezero crater as "Octavia E. Butler Landing". 8 March 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. 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. Study results indicate that limiting global warming to 1.5 °C would prevent most of the tropics from reaching the wet-bulb temperature of the human physiological limit. A new global food emissions database indicates that food systems are responsible for one third of the global anthropogenic GHG emissions. Scientists report that some of Elysia marginata sea slugs can shed and regenerate their parasitised whole body from their head which is capable of photosynthesis. 9 March: Erik Lentz describes a way warp drives sourced from known and familiar purely positive energy could exist. 9 March Physicists report that according to their theoretical model traversable microscopic wormholes may be possible and not require any exotic matter. 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. 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. Scientists use novel lipid nanoparticles to deliver CRISPR genome editing into the livers of mice, resulting in a 57% reduction of LDL cholesterol levels. 10 March Researchers describe a CRISPR-dCas9 epigenome editing method for a potential treatment of chronic pain, an analgesia that represses Nav1.7 and showed therapeutic potential in three mouse models of pain. 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. A study published on 15 March estimates the strain's mortality-risk to be ~61% (42–82%) higher than that of pre-existing variants. 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. A new microscopy technique using a hyperbolic metamaterial is shown to boost imaging resolutions, from 200 nanometres down to 40 nanometres. 11 March: A review finds that the Amazon basin currently emits more greenhouse gases than it absorbs overall. 11 March – Results of a scientific synthesis indicate that, in terms of global warming, the Amazon basin with the Amazon rainforest now emits more greenhouse gases than it absorbs overall due to climate change impacts and human activities in the area – mainly deforestation. 15 March – Scientists report the discovery of a new unknown bacteria species, for the first time, of Methylobacterium, tentatively named Methylobacterium ajmalii, associated with three new strains, designated IF7SW-B2T, IIF1SW-B5, and IIF4SW-B5, on the International Space Station. 16 March – Scientists present evidence that the interstellar object ‘Oumuamua may likely be a piece of a planet similar to Pluto from beyond the Solar System, ejected ~0,5 bn years ago. 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. 18 March – A study finds that the severity of heatwave and drought impacts on crop production roughly tripled over the last 50 years in Europe. 24 March: A view of the M87* supermassive black hole in polarised light 19 March 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. Physicists confirm the first detection of an odderon, based on data collected from CERN's Large Hadron Collider. 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. 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. 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. 24 March A collaboration of scientists using the Event Horizon Telescope present the first polarized-based image of a black hole, at the center of Messier 87, revealing the forces giving rise to quasars. Scientists report that a delayed change in the shape of early brain cells causes the distinctly large human forebrain compared to other apes and identify a genetic regulator of it, ZEB2. 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. 29 March Tokamak Energy announces "first plasma" with its newly-upgraded prototype fusion reactor, the ST40. A study estimates that the national trade-, production- and consumption-patterns of the G7 drive an average annual loss of 3.9 trees per capita. A case-control study of cities finds that redistributing street space for cycling infrastructure – for so-called "pop-up bike lanes" – during the COVID-19 pandemic lead to large additional increases in cycling. The extensive pesticide pollution risks worldwide are estimated with a new environmental model. 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. 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. The first 3D atomic imaging of an amorphous solid is presented, showing the 18,000 atoms in a particle of metallic glass. A report about the leading causes of death in the U.S. for 2020 is published.

April

Science Summary video for this section

2 April: Scientists describe how the dinosaur-killing impact is an origin of neotropical rainforests like the Amazonia and replaced its species composition.

• 2 April – Scientists report that the event that caused the mass-extinction of dinosaurs gave rise to neotropical rainforest biomes like the Amazonia, replacing species composition and structure of local forests. During ~6 million years of recovery to former levels of plant diversity, they evolved from widely spaced gymnosperm-dominated forests to the forests with thick canopies which block sunlight, prevalent flowering plants and high vertical layering as known today.

6 April: A study finds that carbon emissions from Bitcoin mining within China are about to exceed the total annual carbon emissions of countries like Italy (within an estimated ~3 years).

• 6 April
  • 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.
  • COVID-19 pandemic: Scientists report the "estimated incidence of a neurological or psychiatric diagnosis in the following 6 months" after diagnosed COVID-19 infection was 33.62% with 12.84% "receiving their first such diagnosis" and higher risks being associated with COVID-19 severity.

12 April: The construction of the first (eco-)house 3D printed from clay, Tecla, is completed.

• 7 April
  • Physicists report that results from muon g-2 studies involving the muon subatomic particle challenge the Standard Model and, accordingly, may require an updating of currently understood physics.
  • The NOAA reports the largest annual increase in methane emissions since records began, with a rise of 14.7 parts per billion (ppb) in 2020.
  • 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.
  • Scientists report one of the two oldest known reconstructed modern human genomes to date (~45.000 ya) which was found in Czechia, includes long Neanderthal segments and considered to be close to a population that later branched to present-day Europeans and Asians.
  • 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.
• 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. 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. 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.
• 9 April
  • Neuralink reveals a male macaque with chips embedded on each side of its brain, playing a mind-controlled version of Pong.
  • Scientists show that the brains of early Homo from Africa and Dmanisi, Western Asia "retained primitive, great ape-like organization of the frontal lobe" until ~1.5 million years ago and therefore long after Homo emerged and first dispersed from Africa – much later than previously thought (~2.5 Mya).
  • Scientists present a tool for epigenome editing, CRISPRoff, that can heritably silence the gene expression of "most genes" and allows for reversible modifications.
• 12 April
  • The magazine Scientific American announces that it will stop using the term "climate change" in articles about human-caused global warming and substitute "climate emergency" instead.
  • News outlets report that the first prototype 3D printed house made out of clay, Tecla, has been completed. The low-carbon housing was printed by two large arms from a mix that includes locally sourced soil and water. Such buildings could be highly cheap, well-insulated, stable, get produced rapidly, require only very little easily learnable manual labor, mitigate carbon emissions from concrete, require less energy, reduce homelessness, help enable intentional communities, and enable the provision of housing for victims of natural disasters as well as for migrants to Europe near their homes, rather than political facilitation of their influx.
  • Scientists develop a prototype and design rules for both-sides-contacted silicon solar cells with conversion efficiencies of 26% and above, Earth's highest for this type of solar cell.
• 13 April
  • Scientists report the discovery of a billion-years-old, likely holozoan, protist, Bicellum brasieri, showing that the evolution of differentiated multicellularity – such as of animal lineages – occurred at least 1 bn years ago and possibly mainly in freshwater lakes rather than the ocean.
  • In a preprint, an astronomer describes for the first time how one could search for quantum communication transmissions sent by ETI using existing telescope and receiver technology. He also provides arguments for why future searches of SETI should also target interstellar quantum communications.
  • 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.
• 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.

19 April: The semi-autonomous Ingenuity performs the first powered aircraft flight on another planet in human history.

29 April: The first, core module of the Chinese Tiangong space station is put into orbit.

• 15 April
  • COVID-19 pandemic: The CDC, according to numerous media sources, reports that there were 5,800 COVID-19 breakthrough infections, and 74 deaths, in people fully vaccinated for the COVID-19 virus. On 21 April, scientists report that in a cohort of 417 vaccinated persons 2 women had vaccine breakthrough infections and identify their variants' viral mutations.
  • Scientists report the creation, for the first time, of human-monkey hybrid embryos.
  • Biologists report that an estimated 2.5 billion adult Tyrannosaurus rex dinosaurs roamed the Earth over the 2.4 million years of their existence.
  • 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.
  • Researchers demonstrate the whitest ever paint formulation, which reflects up to 98.1% of sunlight and could be used in place of air conditioners.
• 16 April – Scientists report that in the case of Alaskan forests, such boreal forests recovered from wildfires by shifting to a deciduous-coniferous mix, which could offset the carbon emitted during the fires.
• 17 April – New Horizons reaches a distance of 50 astronomical units (AU) from the Sun, while remaining fully operational.
• 19 April – NASA's Ingenuity helicopter, part of the Mars 2020 mission, performs the first powered aircraft flight on another planet in history. The test location is named "Wright Brothers Field".
• 20 April
  • Perseverance performs a test of its MOXIE instrument to convert carbon dioxide into oxygen for the first time on Mars.
  • The Ivanti Pulse Connect Secure data breach of unauthorized access to the networks of high-value targets since at least June 2020 via CVE-2021-22893 across the U.S. and some E.U. nations due to their use of vulnerable, proprietary software is reported.
  • 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".
• 23 April
  • A malaria vaccine with 77% efficacy after 1 year – and first to meet the WHO's goal of 75% efficacy – is reported by the University of Oxford.
  • Scientists report that of ~39 million groundwater wells 6-20% are at high risk of running dry if local groundwater levels decline by a few meters, or – as with many areas and possibly more than half of major aquifers – continue to decline.
• 27 April – Astronomers report the discovery of TOI-1431b, an "ultra-hot Jupiter" with a dayside temperature of ~3,000°K (2,700 °C), making it one of the hottest exoplanets found to date.
• 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.

May

Science Summary video for this section

• 1 May
  • A study that follows up on the randomized Abecedarian Early Intervention Project shows that 5 years of cognitively and linguistically stimulating center-based care starting between 3 and 21 weeks of age can result in significant changes in midlife brain structure in males.
  • A meta-analysis of randomized trials suggests that lowering blood pressure at normal or high-normal blood pressure ranges is effective for prevention of major cardiovascular disease.
• 4 May
  • Genetic signatures linked to extreme longevity in humans are identified by researchers and include genes for efficient DNA repair.
  • A study assesses benefits of fast action to reduce methane emissions when compared to slower climate change mitigation of this form. On 6 May a U.N. report assesses benefits and costs of rapidly mitigating methane emissions.
• 5 May – Scientists report that Mediterranean diets protect against memory decline and mediotemporal atrophy such as in Alzheimer's by decreasing amyloidosis and tau-pathology.
• 6 May
  • Researchers find that China's CO₂ emissions surpassed that of all OECD countries combined for the first time in 2019. 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.
  • Researchers report that bees were successfully trained to detect COVID-19 infections via samples.
  • Researchers publish the first in-depth study of Web browser tab interfaces in over a decade and provide UI design considerations.
• 7 May
  • Operation of the U.S. Colonial Pipeline is interrupted by a ransomware cyber intrusion.
  • Researchers address a key problem of perovskite solar cells by increasing their stability and long-term reliability with a form of "molecular glue".
  • Two studies complement research published September 2020 (see item) by quantum-entangling two mechanical oscillators.
• 10 May – A pan-coronavirus mRNA nanoparticle vaccine with activity against all major SARS-CoV-2 variants is described in Nature, showing potent effect in macaques.
• 11 May
  • NASA reports on the continuous measurement, for the first time, of the density of material in interstellar space by the Voyager 1 space probe and the detection of interstellar sounds of vibrations of dense interstellar plasma.
  • A new record for the smallest single-chip system is achieved, occupying a total volume of less than 0.1 mm³.
  • 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.
  • News reports inform about open source oxygen concentrators of which some are developed, locally manufactured – with prices below imported products – and used during a COVID-19 pandemic wave in India.
  • 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.
• 12 May
  • Scientists report to the United States Congress of the continuing threat of COVID-19 variants and COVID-19 escape mutations.
  • 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.
  • A UK Biobank study finds that alcohol consumption itself harms the brain even at low doses per structural and functional MRI brain measures of over 25 000 individuals of age 54.9±7.4 years such as reducing brain grey matter volume.
• 14 May
  • The China National Space Administration lands its Zhurong mission spacecraft at Utopia Planitia on Mars, making China the second nation to deliver a rover to the planet.
  • 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.
• 17 May – The largest, UK Biobank-based, genome-wide association study of mitochondrial DNA unveils 260 new associations with phenotypes including lifespan and disease risks for e.g. type 2 diabetes.
• 18 May – Google demonstrates a research project called LaMDA, an automatic language generation system designed to sustain a conversation with a person on any topic.
• 19 May – CRISPR gene editing is demonstrated to decrease LDL cholesterol in vivo in Macaca fascicularis by 60%.
• 20 May – A new record high resolution for atomic imaging is reported, with instrumental blurring reduced to less than 20 picometres.
• 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.
• 24 May – Researchers partially restore eyesight of a patient with Retinitis pigmentosa using eye-injected viral vectors for genes encoding the light-sensing channelrhodopsin protein ChrimsonR found in glowing algae, and light stimulation of them via engineered goggles that transform visual information of the environment.
• 25 May
  • 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.
  • The maximum lifespan for humans is placed at between 120 and 150, according to a longitudinal analysis of blood markers.
  • Scientists elaborate mechanics of memory consolidation during sleep which may allow purposely enabling or strengthening this reactivation of experiences and information.
• 26 May
  • After serious news reports by large media outlets within the U.S. and a debate including former and present civil servants in anticipation of a report by the Pentagon, small but increasing numbers of scientists start to publicly discuss UFOs and their investigation in a sober manner on large platforms.
  • Scientists develop a light-responsive days-lasting modulator of circadian rhythms of tissues via Ck1 inhibition which may be useful for chronobiology research and repair of organs that are "out of sync".
• 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.
• 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.
  • China's EAST tokamak sets a new world record for superheated plasma, sustaining a temperature of 120 million degrees Celsius for 101 seconds and a peak of 160 million degrees Celsius for 20 seconds.
• 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.
• 30 May – The most comprehensive 3D map of the human brain – of a 1 mm³ sized millionth of a brain and requiring 1.4 petabytes of storage space – is published.

June

Science Summary podcast based on this section

• 2 June
  • NASA selects DAVINCI+ and VERITAS, two proposed spacecraft to study the atmosphere and surface of Venus, as the next missions in its Discovery Program.
  • 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.
  • 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.
• 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 strategic decision-making.

7 June: Astronomers report detecting substantial amounts of methane, a possible sign of microbial life, on Enceladus.

• 7 June
  • Astronomers report detecting substantial amounts of methane, a possible sign of microbial life, on Enceladus, a moon of the planet Saturn.
  • Biologists report the restoration of bdelloid rotifers after being frozen for ~24,000 years in the Siberian permafrost.
  • The Juno spacecraft performs its only flyby of Jupiter's moon Ganymede, the first flyby of the moon by any spacecraft in over 20 years.
• 8 June – Toshiba achieves quantum communications over optical fibres exceeding 600 km in length, a new world record distance.
• 9 June
  • Astronomers at the Canadian Hydrogen Intensity Mapping Experiment (CHIME) report the detection of over 500 Fast Radio Bursts from outer space.
  • Researchers from Google report a machine learning approach for microchip floorplanning that can outperform human designers.
  • Researchers report the development of quantum nonlinear light microscopy with higher sensitivity and beyond the biological photodamage limit.

10 June: Researchers report the development of a plant proteins-based biodegradable packaging alternative to plastic molecularly similar to high-strength spider silk.

• 10 June
  • A trial of mosquitoes infected with Wolbachia bacteria results in a 77% reduction of dengue fever incidence and 86% reduction of hospitalisations in Yogyakarta, Indonesia.
  • A Venus-orbiting spacecraft, EnVision, is chosen by the European Space Agency as the fifth Medium-class mission in its Cosmic Vision plan, targeting a launch in the early 2030s.
  • Researchers report the development of the first quantum brain scanner which uses magnetic imaging and could become a novel whole-brain scanning approach.
  • Researchers report the development of a plant proteins-based biodegradable packaging alternative to plastic molecularly similar to high-strength spider silk.

11 June: Biologists report that DNA polymerases, long thought to only transcribe DNA into DNA or RNA, can also write RNA segments into DNA.

• 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.
• 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.

15 June: 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.

• 15 June
  • Scientists report measurements of the rapidly increasing rate of the Earth's energy budget imbalance of global warming.
  • 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.
• 16 June – Astronomers report that the Great Dimming of Betelgeuse, a red supergiant star, resulted from expulsion of a substantial amount of dust from the star, and not a sign of its destruction.

22 July: DeepMind's AlphaFold AI maps the 3D structures of 350,000 proteins

28 July: The first direct observation of light from behind a black hole.

• 17 June
  • The first, three-person crew is sent to the Chinese space station Tiangong, which to date consists of the first and core module Tianhe.
  • Researchers present a quantum computing demonstrator that fits inside two 19-inch racks, the world's first quality standards-meeting compact quantum computer.
• 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.
• 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.
• 23 June
  • Astronomers report the determination of 1,715 stars (with likely related exoplanetary systems) within 326 light-years (100 parsecs) that have a favorable positional vantage point—in relation to the Earth Transit Zone (ETZ)—of detecting Earth as an exoplanet transiting the Sun since the beginnings of human civilization (about 5,000 years ago).
  • A study finds that over half of a cohort of home-isolated young patients (16–30 y.) infected with COVID-19 still had symptoms after 6 months, including fatigue (21%).
• 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.
• 25 June
  • Chinese archaeologists report that a skull discovered in Harbin in 1933 by a Manchukuo National Railway bridge, known as Homo longi or "Dragon Man", belongs to a previously undiscovered species of early humans closely related to Homo sapiens dating back 146,000 years ago.
  • The first comprehensive analysis of a Nesher Ramla Homo individual (120–140 kya) suggests an unrecognized group of hominins may have existed and, admixed with Neanderthals, was involved in the evolution of Middle Pleistocene Homo in Europe and East Asia.
  • Scientists report that natural immunity to COVID-19 via forms of prior infection combined with vaccination synergizes to extraordinarily large immune responses.
• 26 June – The first, small clinical trial of CRISPR gene editing in which a – lipid nanoparticle formulated – CRISPR (with mCas9) gene editing therapeutic is injected in vivo into bloodstream of humans concludes with promising results.
• 28 June
  • Scientists publish calculations of water activity levels in Venusian clouds based on data from space probes, concluding these to be two magnitudes too low at the examined places for a natural microbiotic explanation for potentially detected phosphine on Venus.
  • Researchers report the development of embedded biosensors for pathogenic signatures – such as of SARS-CoV-2 – that are wearable such as face masks.
• 29 June
  • The first detection of a neutron star–black hole collision is reported, with a second such event following 10 days later.
  • 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.
  • Scientists report that solar-energy-driven production of microbial foods from direct air capture substantially outperforms agricultural cultivation of staple crops in terms of land use.
• 30 June
  • 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 our Sun.
  • A study of the Laacher See volcano uses dendrochronology and radiocarbon dating to narrow the time of the eruption to 13,006 BP with an error of just 9 years, and shows that the onset of the Younger Dryas happened synchronously over the entire North Atlantic and Central European region. The results directly rule out the Laacher See eruption hypothesis as the cause for the younger dryas (due to the 200 ± 21 year gap), giving more weight to the Younger Dryas impact hypothesis.

July

• 1 July – Construction begins on the Square Kilometre Array, with first light planned for 2027.
• 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.
• 10 July – Scientists report in a preprint the discovery of long extrachromosomal DNA structures, they call borgs, which appear to incorporate genes from organisms it encounters. 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, 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 they may augment.
• 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; more specifically, the isotope Carbon-13 (¹³C) 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.
• 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: 319 Tbit/s, beating the previous record of 178 Tbit/s.
• 22 July
  • Astronomers using the Atacama Large Millimetre/submillimeter Array (ALMA) 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 mapped the structures of 350,000 proteins, including 98.5% of the 20,000 proteins in the human body. The 3D data is made freely available on 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 on or near Earth via telescope technology.
• 28 July
  • The first direct observation of light from behind a black hole is reported, 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 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.

August

9 August: The IPCC begins releasing its next major report on climate change.

• 5 August – New observations of the M-type star L 98-59 and its surrounding system reveal three new bodies: a planet in the habitable zone, an ocean world, and a planet with half the mass of Venus, making it the lightest exoplanet ever to be measured using the radial velocity method.
• 9 August – The Intergovernmental Panel on Climate Change releases the first part of its Sixth Assessment Report, which concludes that the effects of human-caused climate change are now "widespread, rapid, and intensifying".

Predicted and scheduled events

See also: 2021 in spaceflight

• July – Sloan Digital Sky Survey's final data release of SDSS-IV including final data products and catalogs.
• 16 October – Lucy, a planned NASA space probe that will flyby five Jupiter trojans, asteroids which share Jupiter's orbit around the Sun, orbiting either ahead of or behind the planet and one main belt asteroid, is scheduled for launch.
• November – The James Webb Space Telescope, "NASA's most powerful and complex space telescope," is scheduled to launch.
• November – Planned launch of NASA's Artemis 1 mission to the Moon, the first integrated flight of the agency's Orion MPCV and Space Launch System (SLS) rocket.
• 1 November – 12 November – The 2021 UN Climate Change Conference is scheduled to take place in Glasgow, Scotland, United Kingdom. It was rescheduled from November 9, 2020 due to the COVID-19 pandemic.
• 24 November – Double Asteroid Redirection Test (DART), a planned space probe that will demonstrate the kinetic effects of crashing an impactor spacecraft into an asteroid moon for planetary defense purposes, intended to test whether a spacecraft impact could successfully deflect an asteroid on a collision course with Earth, is scheduled for launch.

Date unknown

• Mid/late-2021 – Science first light of the Vera C. Rubin Observatory is anticipated for 2021 with full science operations to begin a year later.
• Plan S, an initiative for open-access science publishing launched in 2018, requires that from 2021 papers from over 10 European countries that resulted from research funded by public grants must be published under an open licence in compliant journals or platforms, available to all.

Astronomical events

• 19 November – a partial lunar eclipse will occur.
• 4 December – a total solar eclipse will occur.

Awards

Main article: Lists of science and technology awards

• Abel Prize: Avi Wigderson and László Lovász

Deaths

• 4 January – Martinus J. G. Veltman, Dutch theoretical physicist and Nobel Prize laureate (b. 1931)
• 28 January – Paul J. Crutzen, Dutch meteorologist and atmospheric chemist, Nobel Prize laureate (b. 1933)
• 16 February – Bernard Lown, Lithuanian-born American inventor and cardiologist (b. 1921)
• 1 April – Isamu Akasaki, Japanese engineer and physicist, Nobel Prize laureate (b. 1929)
• 4 April– Robert Mundell, Canadian economist (b. 1932)
• 4 June – Richard R. Ernst, Swiss physical chemist, Nobel Prize laureate (b. 1933)
• 6 June – Ei-ichi Negishi, Japanese chemist, Nobel Prize laureate (b. 1935)
• 23 July – Toshihide Maskawa, Japanese physicist, Nobel Prize laureate (b. 1940)
• 23 July – Steven Weinberg, American physicist, Nobel Prize laureate (b. 1933)

See also

• Category:Science events
• Category:Science timelines
• Impact of the COVID-19 pandemic on science and technology
• Category:Scientific and technical responses to the COVID-19 pandemic
  • Use and development of software for COVID-19 pandemic mitigation
• List of technologies
• List of emerging technologies
• List of years in science

External links

• Media related to 2021 in science at Wikimedia Commons