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A nearby exoplanet orbiting within the habitable zone of a star just 4.2 light-years from Earth may be home to a vast ocean, boosting its chances of supporting life. Since its discovery, questions about the conditions at the surface of Proxima b have been swirling; the planet’s mass is just about 1.3 times that of Earth’s, and the red dwarf star it circles is similar in age to our sun. Studies over the last few years, however, have both bolstered hopes of its habitability and shot them down. Now, a new study has once again raised the possibility that Proxima...

Scientists reveal the potential for massive, and potentially destructive, eruptions from the sun. On May 1, 2019, the star next door erupted. In a matter of seconds, Proxima Centauri, the nearest star to our sun, got thousands of times brighter than usual — up to 14,000 times brighter in the ultraviolet range of the spectrum. The radiation burst was strong enough to split any water molecules that might exist on the temperate, Earth-sized planet orbiting that star; repeated blasts of that magnitude might have stripped the planet of any atmosphere. It would be bad news if the Earth’s sun ever...

Last December news leaked that the Breakthrough Listen project, part of the Search for Extraterrestrial Intelligence (SETI), had picked up an unexplained signal from the direction of Proxima Centauri. Although everyone involved stressed how unlikely it was that our first evidence for alien intelligence would come from the nearest star to our Sun, some dared to hope. Further research, however, has made Earth-based interference a near-certain explanation. There are many reasons to study Proxima Centauri besides the possibility of technological radio emissions. Australia’s giant Murriyang radio telescope was pointed towards the star primarily to study stellar flares, but in the...

Artist's impression of a flare from Proxima Centauri. (Mark Myers/OzGrav We already had a bit of an inkling that our nearest stellar neighbour might be an inhospitable place. In 2017, red dwarf Proxima Centauri was caught belching out a colossal flare 10 times more powerful than the largest eruptions from the Sun, dampening hopes for habitable conditions on the rocky world orbiting it, Proxima Centauri b. The outlook for life as we know it just got even more grim. A new discovery has given us evidence that Proxima Centauri may be releasing Sun-like coronal mass ejections, in which vast quantities...

Dr. Marin and Dr. Beluffi begin their latest study by considering the various concepts that have been proposed for making an interstellar journey...also took into account missions that will be launching in the coming years like NASA’s Parker Solar Probe. This probe will reach record-breaking orbital velocities of up to 724,205 km/h, which works out to about 200 km/s (or 0.067% the speed of light). With their baseline for speed and travel time established – 200 km/s and 6300 years – Dr. Marin and Dr. Beluffi then set out to determine the minimum number of people needed to ensure that...

If you thought NASA was playing the long game with its plan to put people on Mars in the 2030s, you haven't seen anything yet. New Scientist has learned that a team at the administration's Jet Propulsion Laboratory has started planning a mission that would send a spacecraft to the Alpha Centauri system in... 2069. Yes, that's 52 years away, and timed around the 100th anniversary of Apollo 11's trip to the Moon. The probe would look for signs of life around the potentially habitable exoplanet Proxima b, giving humanity a much better look than it could get with observation...

The proposed journey, which was revealed by scientists with NASA’s Jet Propulsion Laboratory at the 2017 Geophysical Union Conference and reported by New Scientist, was born out of a budget mandate to make progress on interstellar travel. Now, NASA is working on technology that, if all goes as planned, could allow a spacecraft to reach ten percent of light speed, and the goal is to have it ready by 2069 with Alpha Centauri in its sights. ... The system is around 4.3 light years from Earth, which essentially makes it a next-door neighbor. If NASA succeeds at achieving ten percent...

Beam-Riding and Sail Stability by Paul Gilster on June 23, 2017 Breakthrough Starshot, the ambitious 30-year plan for launching small interstellar craft to a nearby star, depends critically on the sails that will ride a laser beam to 20 percent of lightspeed. In the essay below, James Benford takes a hard look at where we are now in the matter of sail stability, a subject he and brother Gregory have analyzed in their laboratory work. But as Jim points out, there is a great deal we still don’t know, emphasizing the need for a dedicated test facility in which deep...

In August of 2016, the European Southern Observatory announced that the nearest star to our own – Proxima Centauri – had an exoplanet. Since that time, considerable attention has been focused on this world (Proxima b) in the hopes of determining just how “Earth-like” it really is.... This is largely due to the fact that Proxima b orbits a red dwarf. Typically, these low mass, low temperature, slow fusion stars are not known for being as bright and warm as our Sun. However, a new study produced by researchers at the Harvard Smithsonian Center for Astrophysics (CfA) has indicated that...

For starters, to call a planet “Earth-like” generally means that it is similar in composition to Earth. This is where the term “terrestrial” really comes into play, as it refers to a rocky planet that is composed primarily of silicate rock and metals which are differentiated between a metal core and a silicate mantle and crust. ... What this does not mean, at least not automatically, is that the planet is habitable in the way Earth is. Simply being terrestrial in nature is not an indication that the planet has a suitable atmosphere or a warm enough climate to support...

The hunt for exoplanets has been heating up in recent years. Since it began its mission in 2009, over four thousand exoplanet candidates discovered by the Kepler mission, several hundred of which have been confirmed to be “Earth-like” (i.e. terrestrial). And of these, some 216 planets have been shown to be both terrestrial and located within their parent star’s habitable zone (aka. “Goldilocks zone”).

In an attempt to leapfrog the planets and vault into the interstellar age, a bevy of scientists and other luminaries from Silicon Valley and beyond, led by Yuri Milner, the Russian philanthropist and Internet entrepreneur, announced a plan on Tuesday to send a fleet of robots no bigger than iPhones to Alpha Centauri, the nearest star system, 4.37 light-years away. If it all worked out — a cosmically big “if” that would occur decades and perhaps $10 billion from now — a rocket would deliver a “mother ship” carrying a thousand or so small probes to space. Once in orbit,...

While we think of stars as being very distant, there is one star system that is relatively close - Alpha Centauri, just 4.3 light-years away. In 2012, astronomers discovered a planet in that system; it orbited way too close to its parent star to be considered habitable, but it got a lot of attention because the exoplanet was so close to Earth. ... The mission (which is not funded right now) is called Alpha Centauri Exoplanet Satellite, or ACESat, and it would work differently than the famed Kepler telescope that has found more than 1,000 confirmed planets. Kepler looks for...

Scientists have spotted one of the largest stellar flares ever recorded in our galaxy. The jets of plasma shot outward from the sun's nearest neighbor, the red dwarf star Proxima Centauri. The flare, which was around 100 times more powerful than any experienced in our solar system, could change the way scientists think about solar radiation and alien life.Proxima Centauri is a red dwarf — the smallest, dimmest and most common type of main sequence stars in the galaxy — located approximately 4.25 light-years from Earth. Its mass is only one-eighth of the sun's, and it is orbited by two...

A new exoplanet only 4.2 light years away would prove that there's plenty left to discover in our own cosmic backyard. Scientists have found evidence of a new exoplanet candidate orbiting our closest stellar neighbor, Proxima Centauri. This exoplanet candidate, Proxima c, likely has a mass six times that of Earth. But it's unlikely that life would survive on the planet, given its frigid temperatures. ----------------------------------------------------------------------- The red dwarf star Proxima Centauri is our closest stellar neighbor; the star system is a measly 4.2 light years from Earth and can be seen with the naked eye. Because of this proximity,...

Before man can cross the vast distances of space, the designs of spacecraft’s sails will be key – striking a delicate balance between mass, strength in addition to reflectivity. Working with NASA, California Institute of Technology (Caltech) scientists have created the fresh material out of silicon in addition to its oxide, silica. The team has figured out that will super-thin structures made of This specific composite can transform infrared light waves into a momentum that will would likely accelerate a probe to 134,000,000 mph. Speeds like This specific can carry a little probe to our closest stellar neighbours, a huddle...

A civilization in the habitable zone of a dwarf star like Proxima Centauri might find it hard to get into interstellar space with conventional rocketsAlmost all space missions launched so far by our civilization have been based on chemical propulsion. The fundamental limitation here is easy to understand: a rocket is pushed forward by ejecting burnt fuel gases backwards through its exhaust. The characteristic composition and temperature of the burnt fuel set the exhaust speed to a typical value of a few kilometers per second. Momentum conservation implies that the terminal speed of the rocket is given by this exhaust...

Proxima Centauri, the closest star to the sun, recently burst forth with one of the most powerful flares ever seen for a star its size. The small red dwarf is generally invisible to the human eye, but this flare may have lit it up bright enough for some naked eye observers to see the event—at least under the right conditions, according to Alison Youngblood, a postdoctoral fellow at NASA Goddard Space Flight Center. According to the team's findings, the star brightened by a factor of 68 during the "superflare," unleashing 316,227,766,000 petajoules (316,227 petawatts) of energy. Proxima Centauri is just...

Astronomers have detected a massive stellar flare -- an energetic explosion of radiation -- from the closest star to our own Sun, Proxima Centauri, which occurred last March. This finding raises questions about the habitability of our Solar System's nearest exoplanetary neighbor, Proxima b [an Earth-like planet], which orbits Proxima Centauri.

Despite being only 4.3 light-years away from Earth, the trio of stars comprising Alpha Centauri still holds a lot of mysteries. It being the closest star system to us, you'd think we'd have teased out most of its secrets by now, but in fact we're still learning basic stuff about it. We know some of the basics, of course. The system has two stars that orbit each other in a binary, one of which (called Alpha Centauri A) is much like the Sun and the other (Alpha Cen B) is a tad smaller and cooler. Nearby is a third star,...