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Mercury (planet)
Mercury is the innermost and smallest planet in the solar system, orbiting the Sun once every 88 days. It ranges in brightness from about −2.0 to 5.5 in apparent magnitude, but is not easily seen; its greatest angular separation from the Sun (greatest elongation) is only 28.3° (it can only be seen in twilight). Comparatively little is known about the planet: the only spacecraft to approach Mercury was Mariner 10 from 1974 to 1975, which mapped only 40 to 45 percent of the planet's surface.
Physically, Mercury is similar in appearance to the Moon as it is heavily cratered. It has no natural satellites and no substantial atmosphere. The planet has a large iron core which generates a magnetic field about 1 percent as strong as that of the Earth. Surface temperatures on Mercury range from about 90 to 700 K (-180 to 430°C) , with the subsolar point being the hottest and the bottoms of craters near the poles being the coldest.
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Space & Time News
October 3, 2026
Oct. 3, 2026 Ultra-detailed simulations are showing how the first stars lit up the dark Universe and seeded space with elements such as carbon, oxygen, and iron. The MEGATRON project could bridge JWST observations of the earliest galaxies with chemical clues ...
Oct. 2, 2026 NASA’s Roman Space Telescope has demonstrated remarkable pointing stability and given its powerful planet-imaging coronagraph its first look at the cosmos. The telescope can already stay locked on a target with precision comparable to aiming a ...
Sep. 28, 2026 CosmoCube will use the far side of the Moon as a shield from Earth’s radio noise to search for a faint signal from the universe before the first stars existed. The suitcase-sized satellite could reveal how the cosmic dark ages ended and how dark ...
Sep. 28, 2026 Spaceflight may dramatically change the gut within weeks, causing bacteria to break down more protein as food moves more slowly through the intestines. The shift could help explain astronaut constipation and may have wider effects on health, making ...
Sep. 25, 2026 Scientists think beneficial fungi could help transform nutrient-poor lunar and Martian regolith into a material capable of supporting crops. By helping plants access nutrients and withstand harsh conditions, these microbes could someday make ...
Sep. 22, 2026 An amateur astronomer searching satellite maps for a Quebec camping spot accidentally discovered a massive ancient impact crater. Scientists later found shatter cones that confirmed the ...
Sep. 21, 2026 NASA’s Roman Space Telescope has successfully activated its 300-megapixel infrared camera, which will capture enormous stretches of the cosmos with Hubble-like sharpness. Its planet-hunting coronagraph is also working as expected, putting Roman ...
Sep. 18, 2026 NASA’s Roman Space Telescope may now have enough fuel for at least 22 years of science, more than double its original 10 year design life. An extremely precise course correction, extra fuel at ...
Sep. 17, 2026 A pocket-sized, roughly $100 detector can reveal the invisible stream of cosmic particles constantly passing through Earth and even through our bodies. What began as a student physics project is now being used in major experiments, balloon missions, ...
Sep. 13, 2026 Scientists have engineered yeast to turn PET plastic and agricultural waste into ingredients for protein-rich, 3D-printed cookies called µBites. Developed partly for NASA’s Deep Space Food Challenge, the system can produce proteins, fats, ...
Sep. 2, 2026 Solar sails pushed by powerful lasers could reach incredible speeds, but relativity may eventually make the light itself work against them. At around 75% of the speed of light, scattered photons can begin creating drag, adding a surprising obstacle ...
Sep. 1, 2026 NASA has brought two of Swift’s telescopes back online after technical problems derailed a commercial mission intended to rescue the aging observatory by raising its orbit. With atmospheric drag pulling the spacecraft downward faster than ...
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Oct. 3, 2026 ESA’s Juice spacecraft raced past Earth on September 28, using our planet’s gravity to dramatically reshape its path toward Jupiter without burning much fuel. The flyby changed its direction by ...
Oct. 3, 2026 Scientists studying Chang’e-6 lunar soil have discovered a previously unknown magnetic mineral in natural Moon samples: a form of metallic iron called γ-Fe. Found inside tiny impact-glass ...
Oct. 2, 2026 JWST has revealed that galaxies were spreading carbon, oxygen, and other heavy elements through space just 500 million years after the Big Bang. The surprising discovery suggests the young universe ...
Sep. 30, 2026 Astronomers have found strong evidence that some mysterious, minutes-long X-ray flashes are produced when two neutron stars collide and create a magnetar. One record-setting event glowed in X-rays ...
Sep. 30, 2026 NASA’s Perseverance rover has uncovered a surprisingly complicated history of water in Jezero Crater. Scientists expected the crater’s Margin ...
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Sep. 30, 2026 NASA’s SpaceX Crew-13 mission is scheduled to launch four astronauts to the International Space Station on October 1. The Dragon could reach the ...
Sep. 30, 2026 NASA’s Curiosity rover marked 5,000 Martian days by capturing morning and afternoon views that were blended into a striking Mars “postcard.” ...
Sep. 29, 2026 Enceladus may naturally separate and concentrate chemicals from its hidden ocean as droplets slowly freeze and shatter on their way into space. The ...
Sep. 29, 2026 NASA and SpaceX could launch four astronauts to the International Space Station on October 1, with the Dragon spacecraft reaching orbiting outpost less than nine hours after liftoff. Crew-13 will ...