Voyager spacecraft detects 'persistent hum' beyond our solar system

By Amy Woodyatt, CNN

Updated 1846 GMT (0246 HKT) May 11, 2021

Two new missions to Venus -- DAVINCI+ and VERITAS -- have been selected by NASA. These missions will shed light on how Venus became the inhospitable world it is today, despite the fact that it shares many characteristics with Earth.
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Two new missions to Venus -- DAVINCI+ and VERITAS -- have been selected by NASA. These missions will shed light on how Venus became the inhospitable world it is today, despite the fact that it shares many characteristics with Earth.
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This illustration shows the position of NASA's Voyager 1 and Voyager 2 probes outside the heliosphere, a protective bubble created by the sun that extends well past the orbit of Pluto.
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This illustration shows the position of NASA's Voyager 1 and Voyager 2 probes outside the heliosphere, a protective bubble created by the sun that extends well past the orbit of Pluto.
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SPHEREx, the Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer, will study the beginning and evolution of the universe and determine how common the ingredients for life are within the planetary systems found in our galaxy, the Milky Way. It is targeted to launch in 2024.
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SPHEREx, the Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer, will study the beginning and evolution of the universe and determine how common the ingredients for life are within the planetary systems found in our galaxy, the Milky Way. It is targeted to launch in 2024.
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This illustration shows NASA's Dragonfly rotorcraft-lander approaching a site on Saturn's exotic moon, Titan. Taking advantage of Titan's dense atmosphere and low gravity, Dragonfly will explore dozens of locations across the icy world, sampling and measuring the compositions of Titan's organic surface materials to characterize the habitability of Titan's environment and investigate the progression of prebiotic chemistry.
Photos: Cool unmanned space missions
This illustration shows NASA's Dragonfly rotorcraft-lander approaching a site on Saturn's exotic moon, Titan. Taking advantage of Titan's dense atmosphere and low gravity, Dragonfly will explore dozens of locations across the icy world, sampling and measuring the compositions of Titan's organic surface materials to characterize the habitability of Titan's environment and investigate the progression of prebiotic chemistry.
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NASA's Wide Field Infrared Survey Telescope, slated to launch in the mid-2020s, has been named the Nancy Grace Roman Space Telescope, after NASA's first chief astronomer.
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NASA's Wide Field Infrared Survey Telescope, slated to launch in the mid-2020s, has been named the Nancy Grace Roman Space Telescope, after NASA's first chief astronomer.
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This is an artist's concept of the Europa Clipper spacecraft, which will investigate Jupiter's icy moon.
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This is an artist's concept of the Europa Clipper spacecraft, which will investigate Jupiter's icy moon.
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Bright swaths of red in the upper atmosphere, known as airglow, can be seen in this image from the International Space Station. NASA's ICON mission will observe how interactions between terrestrial weather and a layer of charged particles called the ionosphere create the colorful glow.
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Bright swaths of red in the upper atmosphere, known as airglow, can be seen in this image from the International Space Station. NASA's ICON mission will observe how interactions between terrestrial weather and a layer of charged particles called the ionosphere create the colorful glow.
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NASA's Global-scale Observations of the Limb and Disk mission -- known as the GOLD mission -- will examine the response of the upper atmosphere to force from the sun, the magnetosphere and the lower atmosphere.
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NASA's Global-scale Observations of the Limb and Disk mission -- known as the GOLD mission -- will examine the response of the upper atmosphere to force from the sun, the magnetosphere and the lower atmosphere.
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NASA's Transiting Exoplanet Survey Satellite launched in April and is already identifying exoplanets orbiting the brightest stars just outside our solar system. In the first three months since it began surveying the sky in July, it has found three exoplanets, with the promise of many more ahead.
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NASA's Transiting Exoplanet Survey Satellite launched in April and is already identifying exoplanets orbiting the brightest stars just outside our solar system. In the first three months since it began surveying the sky in July, it has found three exoplanets, with the promise of many more ahead.
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This is an artist's concept of the Solar Probe Plus spacecraft approaching the sun. In order to unlock the mysteries of the corona, but also to protect a society that is increasingly dependent on technology from the threats of space weather, we will send Solar Probe Plus to touch the sun.
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This is an artist's concept of the Solar Probe Plus spacecraft approaching the sun. In order to unlock the mysteries of the corona, but also to protect a society that is increasingly dependent on technology from the threats of space weather, we will send Solar Probe Plus to touch the sun.
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This illustration shows light beams from Earth pushing a tiny spacecraft's sail. The proposed Breakthrough Starshot project would send hundreds of "nanocraft" space probes 4.37 light years away -- at speeds of up to 100 million miles an hour -- to to explore Alpha Centauri, our nearest star system. The ambitious project is many years away from becoming reality.