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Somewhat more than 4000 planets orbiting stars outside our solar system are known so far. Of these so-called exoplanets, about 96 percent are significantly larger than our Earth, most of them more comparable with the dimensions of the gas giants Neptune or Jupiter. This percentage likely does not reflect the real conditions in space, however, since small planets are much harder to track down than big ones. Moreover, small worlds are fascinating targets in the search for Earth-like, potentially habitable planets outside the solar system. The 18 newly discovered worlds fall into the category of Earth-sized planets. The smallest of...

hen NASA's New Horizons spacecraft flew past Pluto in 2015, researchers hoped that its data would help them unravel some of the dwarf planet's mysteries. Instead, the discoveries made during the close-up look at Pluto and its moon Charon revealed more questions that needed answering. One of the big revelations from the flyby was the discovery of an ocean beneath the icy shell encapsulating Pluto. The ice shell was thin in a spot near the equator that's about the size of Texas, known as Sputnik Planitia, which helped researchers notice Pluto's odd topography and suggest the ocean's existence. But this...

Toward a High-Velocity Astronomyby Paul Gilsteron May 15, 2019 Couple the beam from a 100 gigawatt laser with a single-layer lightsail and remarkable things can happen. As envisioned by scientists working with Breakthrough Starshot, a highly reflective sail made incredibly thin — perhaps formed out of graphene and no thicker than a single molecule — could attain speeds of 20 percent of c. That’s good enough to carry a gram-scale payload to the nearest stars, the Alpha Centauri triple system, with a cruise time of 20 years, for a flyby followed by an agonizingly slow but eventually complete data return....

Enough gold, uranium and other heavy elements about equal in mass to all of Earth's oceans likely came to the solar system from the collision of two neutron stars billions of years ago, a new study finds. If the same event were to happen today, the light from the explosion would outshine the entire night sky, and potentially prove disastrous for life on Earth, according to the new study's researchers. Recent findings have suggested that much of the gold and other elements heavier than iron on the periodic table was born in the catastrophic aftermath of colliding neutron stars,...

While searching for the source of methane on Saturn’s large moon Titan, researchers found a completely unexpected corridor of methane ice wrapping nearly halfway around the moon. Three orientations of Titan’s globe. The icy corridor is mapped in blue. Image via Caitlin Griffith/UA Lunar and Planetary Laboratory.A research team has discovered huge ice feature on Titan while trying to understand where Saturn’s largest moon gets all of its methane. Like Earth, Titan has rain, seas and a surface of eroding organic material. However, on Titan it is methane, not water, that makes up the raindrops and fills the lakes.A team...

Launched in 2018, TESS is NASA’s new space-based exoplanet hunter. Now it’s found its 1st Earth-sized world orbiting a nearby star. The discovery bodes well, scientists say, for finding more similar worlds in the near future. Artist’s concept of HD 21749c, the first Earth-sized exoplanet discovered by TESS. Image via Robin Dienel/Carnegie Institution for Science.NASA’s newest exoplanet-hunting telescope, the Transiting Exoplanet Survey Satellite (TESS), has now found its first Earth-sized world. It’s the smallest planet TESS has found yet in its still-young mission. Astronomers say it’s another exciting step towards finding worlds beyond our solar system that might be capable of...

Astronomers have managed to capture an amazingly clear image of CVSO 30c - a potential exoplanet orbiting a distant star named CVSO 30, that lies some 1,200 light-years away. Besides being breathtaking to look at, researchers are extra excited about the new photo, because it could mean that CVSO 30 actually has two planets orbiting it instead of just one. Follow-up observations and analysis will be needed to confirm CVSO 30c as a true exoplanet, but if verified, this would be the first star system to host both a close-in exoplanet and a far-out exoplanet. Four years ago, astronomers found...

NASA’s Transiting Exoplanet Survey Satellite (TESS) has found its first Earth-size planet, Space.com reports. The planet, called HD 21749c, orbits a star about 53 light-years from Earth, researchers write this week in The Astrophysical Journal Letters. The rocky HD 21749c circles its star at close range, completing a full orbit every 7.8 Earth days, suggesting to astronomers that it is probably too hot to sustain life. TESS also discovered another planet orbiting the same star that astronomers are calling a “sub-Neptune” after its closest analog in own solar system.

DESI, the Dark Energy Spectroscopic Instrument, will mobilize 5,000 swiveling robots – each one pointing a thin strand of fiber-optic cable – to gather the light from about 35 million galaxies. The little robots are designed to fix on a series of preselected sky objects that are as distant as 12 billion light-years away. By studying how these galaxies are drifting away from us, DESI will provide precise measurements of the accelerating rate at which the universe is expanding. This expansion rate is caused by an invisible force known as dark energy, which is one of the biggest mysteries in...

A dwarf planet discovered over a decade ago is the largest body we know of in our solar system without a proper name – but that’s about to change. Meg Schwamb, an astronomer at Gemini Observatory in Hawaii, and her colleagues have opened a public vote to name the distant world, which is currently known only as 2007 OR10. They have selected three potential names that fit the International Astronomical Union’s (IAU) rules on official names for minor planets, and will recommend the winner to the IAU, which will then select the formal name. So why now, instead of when...

UNSW astronomers have shown that binary stars – two stars locked in orbit around each other – reflect light as well as radiating it, revealing new ways for their detection. One of the first things we learn in astronomy is that some of the objects in the sky (the Sun and the stars) produce their own light, whereas others (the Moon and the planets) are only visible because they reflect light from the Sun. But do the Sun and the stars also reflect some of the light that falls on them? This is a question that scientists from UNSW Sydney...

"Our results support the idea that methane release on Mars might be characterized by small, transient geological events," researcher Frank Daerden said. The European Space Agency's Mars Express probe measured methane in the Martian atmosphere a day after NASA's Curiosity rover detected the gas in Gale Crater. Photo by ESA ============================================================= April 2 (UPI) -- Some 15 years ago, a European probe measured traces of methane in the Martian atmosphere. Now, NASA's Curiosity rover and the European Space Agency's Mars Express have confirmed the gas' presence in the air above Gale Crater. "The presence of methane could enhance habitability and...

It's a large moon, the seventh largest in our solar system, and scientists think it was born in the Kuiper Belt before falling into its current location in orbit around the most distant planet. ...Procktor and her colleagues believe they can photograph the moon's entire surface in a single pass. ...On its way past Triton, the spacecraft's flight would be timed in order to see in sunlight the 60 percent or so of its surface that Voyager 2 couldn't see. After the initial approach, the spacecraft would turn its camera back to recapture the 40 percent of the surface Voyager...

Curiosity rover mission recently determined that background levels of methane in Mars' atmosphere cycle seasonally, peaking in the northern summer. The six-wheeled robot has also detected two surges to date of the gas inside the Red Planet's 96-mile-wide (154 kilometers) Gale Crater — once in June 2013, and then again in late 2013 through early 2014. These finds have intrigued astrobiologists, because methane is a possible biosignature. Though the gas can be produced by a variety of geological processes, the vast majority of methane in Earth's air is pumped out by microbes and other living creatures. Some answers may soon...

GRAVITY works by synching the VLT's four unit telescopes to perform like a bigger, more powerful telescope. For the first time, the Very Large Telescope's GRAVITY instrument has observed a distant exoplanet using optical interferometry. Observations of the exoplanet's atmosphere revealed massive, swirling storm clouds of iron and silicates stretching across the entirety of the alien planet. Astronomers described GRAVITY's feat and shared details about the observed target, exoplanet HR8799e, in a paper published this week in the journal Astronomy and Astrophysics. GRAVITY works by synching the VLT's four unit telescopes to perform like a bigger, more powerful telescope. Astronomers...

The first recorded instance of Uranus being spotted in the night sky is believed to date back to Classical Antiquity. During the 2nd century BCE, Hipparchos - the Greek astronomer, mathematician and founder of trigonometry - apparently recorded the planet as a star in his star catalogue (completed in 129 BCE). This catalog was later incorporated into Ptolemy's Almagest, which became the definitive source for Islamic astronomers and for scholars in Medieval Europe for over one-thousand years... This included English astronomer John Flamsteed, who in 1690 observed the star on six occasions and catalogued it as a star in the...

For almost a decade, astronomers have tried to explain why so many pairs of planets outside our solar system have an odd configuration—their orbits seem to have been pushed apart by a powerful unknown mechanism. Yale researchers say they've found a possible answer, and it implies that the planets' poles are majorly tilted. NASA's Kepler mission revealed that about 30% of stars similar to our Sun harbor "Super-Earths." Their sizes are somewhere between that of Earth and Neptune; they have nearly circular and coplanar orbits; and it takes them fewer than 100 days to go around their star. Yet curiously,...

The records include dates and times, Cesario said, which makes them useful to modern-day astronomers. Planet Nine, if it exists, would have about 10 times the mass of Earth and orbit 20 times farther from the sun than Neptune does... Scientists suspect the existence of Planet Nine because it would explain some of the gravitational forces at play in the Kuiper Belt, a stretch of icy bodies beyond Neptune. But no one has been able to detect the planet yet, though astronomers are scanning the skies for it with tools such as the Subaru Telescope on Hawaii's Mauna Kea volcano....

A new set of images showing the New Horizons spacecraft departing from Ultima Thule following its New Year’s Day closest approach reveals the Kuiper Belt Object (KBO) is shaped less like a snowman and more like a flat object, with one lobe looking like a pancake and the other like a dented walnut. Initial images returned immediately after the flyby suggested the double-lobed object was composed of two nearly-spherical lobes, one larger than the other. Their apparent nearly round shapes were not due to the lobes being rounded by their own gravity, as both are far too small to attain...

ATLANTA - The Sun has a twin, astronomers announced Tuesday. The solar doppelganger hits nearly identical marks in temperature, rotation and age. Planet hunters have it on their lists, but there’s no word yet whether carbon-based folks are looking back at their star’s twin, our own Sun. 18 Scorpii is in the constellation Scorpius, visible in the predawn sky to the south. Finding it requires completely dark skies and a map configured for your location. More Stories The 10 Brightest Stars Strangest Star Known is the 'Talk of Astronomy' Mysteries of the Sun