Astronomy

Jupiter's four Galilean moons will line up in front of Jupiter in the early morning sky on Aug. 8.

Explore the wonders of the cosmos and save over $700 on this Unistellar eQuinox 2 bundle, including an official backpack for taking it to dark sky sites.

Direct images from the James Webb Space Telescope show what could be a Saturn-mass planet around Alpha Centauri.

The post Alpha Centauri Might Have a Planet, Webb Telescope Finds appeared first on Sky & Telescope.

Hundreds of pieces of bone dating from 5700 years ago carry evidence of being processed and eaten by other humans, bolstering the idea that cannibalism was common in the Neolithic period

Hundreds of pieces of bone dating from 5700 years ago carry evidence of being processed and eaten by other humans, bolstering the idea that cannibalism was common in the Neolithic period

An ambitious plan to test extreme physics close to a black hole would involve a space probe weighing only a few grams, travelling at a third of the speed of light

An ambitious plan to test extreme physics close to a black hole would involve a space probe weighing only a few grams, travelling at a third of the speed of light

Scientists have developed an algorithm called Astroclimes, which transforms stargazing instruments into climate sensors that measure greenhouse gases in Earth's atmosphere.

The Artemis II crew (from left to right) CSA (Canadian Space Agency) Jeremy Hansen, mission specialist; Christina Koch, mission specialist; Victor Glover, pilot; and Reid Wiseman, commander, don their Orion Crew Survival System Suits for a multi-day crew module training beginning Thursday, July 31, 2025, at NASA’s Kennedy Space Center in Florida. Behind the crew, wearing clean room apparel, are members of the Artemis II closeout crew.

Astronomers using NASA's James Webb Space Telescope have found strong evidence for a new exoplanet — one orbiting Alpha Centauri A, the nearest sun-like star to Earth.

In some of its most ambitious work yet, the James Webb Space Telescope looked to spot a planet in a potentially habitable orbit around Alpha Centauri A, the nearest sunlike star to our solar system

Astronomers using the NASA/ESA/CSA James Webb Space Telescope have found strong evidence of a giant planet orbiting a star in the stellar system closest to our own Sun. At just 4 light-years away from Earth, the Alpha Centauri triple star system has long been a compelling target in the search for worlds beyond our solar system.

Structured interventions that encourage a good giggle, whether they are laughter yoga or clown visits, could have health benefits

Structured interventions that encourage a good giggle, whether they are laughter yoga or clown visits, could have health benefits

Though the Fibonacci sequence shows up everywhere in nature, these young mathematicians were surprised to find it in the answer to a variation of the pick-up sticks problem⁠—a nearly two-century-old form of puzzle

A solar system model with a small projector built in, the Science Can Solar System Planetary Projector is a great educational tool for kids.

August's full Sturgeon Moon rises this weekend, days before the Perseid meteor shower hits its peak.

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A team of astronomers has taken the sharpest-ever picture of the unexpected interstellar comet 3I/ATLAS, using the crisp vision of the NASA/ESA Hubble Space Telescope.

ESA's Planetary Defence Office responded promptly to the discovery of the comet, and has been tracking it since the beginning of July.

Now, Hubble's observations from space are allowing astronomers to more accurately estimate the size of the comet’s solid icy nucleus. The upper limit on the diameter of the nucleus is 5.6 km, but it could be as small as 320 m across, researchers report.

Though the Hubble images put tighter constraints on the nucleus size compared to previous ground-based estimates, the solid heart of the comet presently cannot be directly seen, even by Hubble. Further observations, including by the NASA/ESA/CSA James Webb Space Telescope, will help refine our knowledge about the comet, including its chemical makeup.

Hubble also captured a dust plume ejected from the Sun-warmed side of the comet, and the hint of a dust tail streaming away from the nucleus. Hubble’s data show that the comet is losing dust in a similar manner to that from previously seen Sun-bound comets originating within our Solar System.

The big difference is that this interstellar visitor originated in some other stellar systems, elsewhere in our Milky Way galaxy.

3I/ATLAS is traveling through our Solar System at roughly 210 000 km per hour, the highest speed ever recorded for a Solar System visitor. This breathtaking sprint is evidence that the comet has been drifting through interstellar space for many billions of years. The gravitational slingshot effect from innumerable stars and nebulae the comet passed added momentum, ratcheting up its speed. The longer 3I/ATLAS was out in space, the higher its speed grew.

This comet was discovered by the Asteroid Terrestrial-impact Last Alert System (ATLAS) on 1 July 2025 at a distance of 675 million km from the Sun. 3I/ATLAS should remain visible to ground-based telescopes until September, after which it will pass too close to the Sun to observe. It is expected to reappear on the other side of the Sun by early December.

Icy wanderers such as 3I/ATLAS offer a rare, tangible connection to the broader galaxy. To actually visit one would connect humankind with the Universe on a far greater scale. To this end, ESA is preparing the Comet Interceptor mission. The spacecraft will be launched in 2029 into a parking orbit, lying in wait for a suitable target – a pristine comet from the distant Oort Cloud that surrounds our Solar System, or, unlikely but highly appealing, an interstellar object.

While it is improbable that we will discover an interstellar object that is reachable for Comet Interceptor, as a first demonstration of a rapid response mission that waits in space for its target, it will be a pathfinder for possible future missions to intercept these mysterious visitors.

The research paper based on Hubble observations will be published in The Astrophysical Journal Letters.

[Image description: At the center of the image is a comet that appears as a teardrop-shaped bluish cocoon of dust coming off the comet’s solid, icy nucleus and seen against a black background. The comet appears to be heading to the bottom left corner of the image. About a dozen short, light blue diagonal streaks are seen scattered across the image, which are from background stars that appeared to move during the exposure because the telescope was tracking the moving comet.]

They don't yet have a name, but "Star Trek: Strange New Worlds"'s latest foes have surely beamed in from a horror movie.

Start preparing now to catch next month's dramatic total lunar eclipse.