Our solar system has several belts of rocky planetesimals that are essentially the crumbs left over from the formation of the planets and moons. But new research suggests some of these objects could actually be alien, captured during close flybys with other star systems. These close encounters could also explain objects like 'Oumuamua and might even provide an alternative to the "Planet Nine" hypothesis.

Scientists at the Max Planck Institute for Solar System Research (MPS), the Georg August University of Göttingen, and the Sonneberg Observatory have discovered 18 Earth-sized planets beyond the solar system. The worlds are so small that previous surveys had overlooked them. One of them is one of the smallest known so far; another one could offer conditions friendly to life. The researchers re-analyzed a part of the data from NASA's Kepler Space Telescope with a new and more sensitive method that they developed.

Do planets harbor life? Or is it their moons that are most likely to support extra-terrestrial lifeforms? According to an astrophysicist at the University of Lincoln, the moons orbiting planets outside our solar system could give us clues about the pool of worlds that may be home to extra-terrestrial life.

Neptune's largest moon Triton boasts an uncommon icy mixture of carbon monoxide and nitrogen, which could help astronomers better understand the conditions of other distant alien worlds. Using the Gemini Observatory in Chili and the high-resolution spectrograph called IGRINS (Immersion Grating Infrared Spectrometer), a visiting instrument for Gemini, astronomers detected a distinct infrared signature on Triton, revealing a mixture of carbon monoxide and nitrogen frozen as solid ice.

Scientists have discovered 18 Earth-sized planets beyond the solar system. The worlds are so small that previous surveys had overlooked them. One of them is one of the smallest known so far; another one could offer conditions friendly to life. The researchers re-analyzed a part of the data from NASA's Kepler Space Telescope with a new and more sensitive method.

A stunning video shot by a Dutch astronomer captured a string of roughly 60 Starlink satellites zooming across the night sky, one day after they were launched into orbit. The video shows the "train" of satellites speeding in a straight line as they orbit around the earth.

For a while now, astronomers have been confronting a conundrum. Studies of the early universe, looking at the era just after the Big Bang, tell us that the cosmos should be expanding at one speed. But when astronomers actually measure today’s universe, they find a faster rate of expansion.

Deep under the Mediterranean Sea, hundreds of watchful eyes hang suspended on cables, waiting for a rare and valuable flash. Their quarry are ghostly neutrino particles, capable of tunneling through light-years of space and a planet’s worth of rock without ever coming into contact with matter.

Astronomers discovered a pulsar, a kind of zombie star, racing across the galaxy so quickly that it could get from Earth to the Moon in six minutes flat. The dead star has a tail pointing back toward the remnant of a supernova that exploded 10,000 years ago. Astronomers suspected this might have provided the kick that sent the pulsar speeding off, but had to wait for 10 years of telescope data to make their case convincing.

The Moon moves eastward relative to the background stars an average of 13° every day, and early tomorrow morning (Friday, March 29), Earth’s only satellite will pass within just 3° of Saturn. The ringed planet rises around 3:15 a.m. local daylight time over the southeastern horizon. The Moon, which currently appears as a waning crescent, follows about 10 minutes later.

The European Southern Observatory has just revealed there will be a huge announcement next week. Yes, we know how that sounds - but as far as we can tell, it appears the world is about to finally see the first ever photo of a black hole's event horizon. Of course, we won't know for sure until the press event itself, which we will cover live on our site. But here's a massive clue: according to the advance statement, the researchers will be discussing the "first result from the Event Horizon Telescope."

Scientists are expected to unveil on Wednesday the first-ever photograph of a black hole, a breakthrough in astrophysics providing insight into celestial monsters with gravitational fields so intense no matter or light can escape. The U.S. National Science Foundation has scheduled a news conference in Washington to announce a “groundbreaking result from the Event Horizon Telescope (EHT) project,” an international partnership formed in 2012 to try to directly observe the immediate environment of a black hole.

Black holes are some of the most intriguing and mysterious objects in the universe, inspiring entire libraries of both scientific research and science fiction, from Einstein to the movie Interstellar. Yet despite the hold their inconceivable gravity has on our imaginations, as well as our understanding of physics, humans have never actually seen a black hole.

A network of eight radio telescopes around the world helped to record the image

Excitement about exoplanets skyrocketed when rocky Earth-like planets were discovered orbiting in the habitable zone of some of our closest stars – until hopes for life were dashed by the high levels of radiation bombarding those worlds. Proxima-b, only 4.24 light years away, receives 250 times more X-ray radiation than Earth and could experience deadly levels of ultraviolet radiation on its surface. How could life survive such a bombardment? Cornell astronomers say that life already has survived this kind of fierce radiation, and they have proof: you.

Like the planet Tatooine from Star Wars, two suns — one bright, one dim and red— rise over the horizon of Kepler 47d. But unlike dry and sandy Tatooine, this planet’s surface is gassy and indistinct. The system also holds two smaller planets; one planet closer to the double suns, and one farther out. Both lack a solid surface. If you visited in a spaceship, all the planets would be easy to spot because they’re packed, along with their stars, into a space smaller than Earth’s orbit around the Sun.

Everything has a beginning. That’s true for stories, for people, for the universe and even for chemistry. The Big Bang itself produced just a handful of elements (variations of hydrogen, helium and lithium nuclei), so researchers have a pretty good sense of what the first atoms and molecules might have been. But the very first molecular bond to form, linking together atoms of different elements in a single molecule, has long been missing in action.

NASA and ESA celebrate the 29th Birthday of the Hubble space telescope on 24th April 2019 with a stunning image of the Southern Crab Nebula.

The smallest planet in our solar system has a massive solid inner core. In its final trip around Mercury before crash-landing in 2015, NASA’s MESSENGER mission zoomed in close to the planet, enabling scientists to make detailed measurements of its gravity, spin and internal structure. Those data, researchers report April 10 in Geophysical Research Letters, suggest Mercury has a solid inner core about 2,000 kilometers in diameter, making up about half of Mercury’s entire core.

The discoveries of thousands of planets orbiting stars outside our solar system has made questions about the potential for life to form on these planets fundamentally important in modern science. Fundamentally important for the habitability of a planet is whether or not it can hold onto an atmosphere, which requires that the atmosphere is not completely lost early in the lifetime of the planet.

New research into data on exoplanets suggests that 'super-Earths' and water-rich 'sub-Neptunes' between two and four times bigger than Earth are likely to be water worlds containing at least 25% water-dominated ices or fluids, and not the gas dwarfs with a rocky core than many astronomers thought.

Astronomers have observed evidence of a hot, spinning star blasting winds outwards at 10,000 miles per second, which seemed to have formed from a relatively recent collision of white dwarf stars. It’s some of the clearest evidence to date of these stars colliding and merging.

Scientists from Ireland and France today announced a major new finding about how matter behaves in the extreme conditions of the Sun’s atmosphere. The scientists used large radio telescopes and ultraviolet cameras on a NASA spacecraft to better understand the exotic but poorly understood “fourth state of matter”. Known as plasma, this matter could hold the key to developing safe, clean and efficient nuclear energy generators on Earth.

Pluto wrongly lost its planet status, say, scientists, suggesting that the icy dwarf should be reclassified as a planetary body. In 2006, the International Astronomical Union (IAU), a global group of astronomy experts, established a definition of a planet that required it to "clear" its orbit, or in other words, be the largest gravitational force in its orbit.

A team of astronomers using the latest set of data from ESA's Gaia mission to look for high-velocity stars being kicked out of the Milky Way were surprised to find stars instead sprinting inwards -- perhaps from another galaxy.

For the second time this year, the five brightest planets can be seen at the same time. You can catch them by looking towards the western sky after sunset. The planets will form a line rising up from the horizon. Mercury and Venus are low to the west, with bright Jupiter shining just above. Higher up in the northwestern sky is Saturn, and completing the set of five is the red planet Mars, high overhead.

New research shows a pattern of exoplanet sizes and spacing around other stars unlike what we see in our own system

There's a telescope that can see thick rings of dust in distant star systems. These rings are huge — wide enough in some cases to encircle most or all the planets in our solar system. And they're the birthplaces of exoplanets. Understanding how they work could teach us about how the planets in our own solar system formed.

Chia Min Tan, a Ph.D. Student based at the Jodrell Bank Centre for Astrophysics in Manchester's School of Physics and Astronomy, was part of an international team including fellow astronomers at Manchester, ASTRON and the University of Amsterdam. The team carried out the observations using the Low-Frequency Array (LOFAR), whose core is located in the Netherlands. Their findings were published in the Astrophysical Journal.

As BepiColombo heads to Mercury — a long-neglected planet — Nature looks at which planets attract scientific missions, and why. Last week, the BepiColombo spacecraft successfully began its seven-year journey to Mercury — only the third-ever mission sent to the planet. The day before, scientists said that NASA’s next Mars rover — intended to be first to gather and return rock samples to Earth — should visit as many places on the red planet as possible.

An astro-photographer has captured the 'once in a lifetime' moment a meteor exploded before disintegrating into the night sky in Shorpshire. The scene, which has been recorded very few times on camera, was caught during an Orionid meteor shower. Orionid meteors occur every Autumn when the Earth is passing through the stream of debris left by Halley's Comet.

Some of the winning images from the Royal Observatory Greenwich's annual competition.

The Gaia satellite has spotted an enormous 'ghost' galaxy lurking on the outskirts of the Milky Way. An international team of astronomers, including from the University of Cambridge, discovered the massive object when trawling through data from the European Space Agency's Gaia satellite. The object, named Antlia 2 (or Ant 2), has avoided detection until now thanks to its extremely low density as well as a perfectly-chosen hiding place, behind the shroud of the Milky Way's disc. The researchers have published their results online today.

About 8,000 light-years from Earth lies a star system unlike any astronomers have ever seen. And within that star system lies a ticking bomb - a gamma-ray burst.

A brisk stroll on Mars’ tiny, potato-shaped moon Phobos may just send you tumbling into space, finds a new report in Advances in Space Research. The new research (which admittedly seems a bit superfluous at first) looked at the latest published models of Phobos’ odd shape and dynamics to study how future exploration missions should navigate in orbit around, or on, the surface of the moon. The weird shape of the puny 14-mile-wide moon means that its gravitational field significantly varies along its surface.