Not Aliens: Weird Radio Signal from Star Likely Has Duller Explanation

Not Aliens: Weird Radio Signal from Star Likely Has Duller Explanation:

The signal that seemed to emanate from the red dwarf star Ross 128, as detected by the Arecibo Observatory in May 2017 (enclosed in the red frame).

Credit: PHL @ UPR Arecibo

A strange radio signal that seemed to emanate from a small nearby star probably came from Earth-orbiting satellites, astronomers say.

Late last week, researchers announced that, on May 12, the 1,000-foot-wide (305 meters) Arecibo radio telescope in Puerto Rico detected a bizarre radio signal in the vicinity of Ross 128, a red dwarf star that lies just 11 light-years from Earth.

The signal was theoretically consistent with a transmission from an alien civilization, the astronomers said, though they stressed that hypothesis was "at the bottom of many other explanations." Indeed, they pegged the leading candidates as flares from Ross 128, emissions from some other object in the same field of view as the star, and a burst from one or more high-orbiting satellites. [13 Ways to Hunt Intelligent Aliens]

Now, follow-up observations — by Arecibo, as well as the Green Bank Telescope in West Virginia and the Allen Telescope Array (ATA) in northern California — point to this last hypothesis as the most likely, team members said.

"The best explanation is that the signals are transmissions from one or more geostationary satellites," Abel Mendez, director of the Planetary Habitability Laboratory at the University of Puerto Rico, wrote in a statement today (July 21). (Geostationary satellites circle Earth at an altitude of about 22,300 miles, or 35,800 kilometers.)

"This explains why the signals were within the satellite’s frequencies and only appeared and persisted in Ross 128; the star is close to the celestial equator, where many geostationary satellites are placed," Mendez added. "This fact, though, does not yet explain the strong dispersion-like features of the signals (diagonal lines in the figure); however, it is possible that multiple reflections caused these distortions, but we will need more time to explore this and other possibilities."

But even though it's likely that the Ross 128 signal has a prosaic explanation, scientists should still follow up on similar detections in the future, stressed Seth Shostak, a senior astronomer at the SETI (Search for Extraterrestrial Intelligence) Institute in Mountain View, California.

"The historic lesson is clear — these things pop up, and you have to follow them up, because you never know what's going to be the real one, or even if there will ever be a real one," Shostak, who was involved in the recent ATA observations of Ross 128, told Space.com earlier this week. "Following up is mandatory."

Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us @Spacedotcom, Facebook or Google+. Originally published on Space.com.

2017 Solar Eclipse Science Will Star Planes, Radio Waves and Citizen Help

2017 Solar Eclipse Science Will Star Planes, Radio Waves and Citizen Help:

This view of a 2010 total solar eclipse combines ground-based views (gray and white) taken from the South Pacific and space-based images from the SOHO spacecraft, which used a coronagraph to block out the sun and thus can't view as close to its surface.

Credit: Williams College Eclipse Expedition - Jay M. Pasachoff, Muzhou Lu and Craig Malamut; SOHO's LASCO image courtesy of NASA/ESA; solar disk image from NASA's SDO; compositing by Steele Hill, NASA's Goddard Space Flight Center

With the 2017 total solar eclipse only one month away, scientists from several science organizations highlighted how studying the sun during an eclipse will help improve understanding of the behavior of Earth's closest stellar neighbor.

The Aug. 21 eclipse's totality path will span 14 different states coast to coast, taking roughly 91 minutes to cross the country. While the location of greatest eclipse is Hopkinsville, Kentucky, the time of totality will average about 2.5 minutes across all locations.

Officials from NASA, the National Science Foundation (NSF) and the National Center for Atmospheric Research (NCAR) came together yesterday (July 21 to discuss their plans during a press conference in Boulder, Colorado. [The Best ISO-Certified Gear to See the 2017 Solar Eclipse]

"The neat thing about this — as a scientist, and is someone who has kids — is the whole lower 48 [states] will be in shadow," said Scott McIntosh, director of NCAR's High Altitude Observatory. Some states will see only partial eclipses, while others will see the sun totally disappear. The event will provide opportunities for millions of amateurs to get involved with the science alongside professional astronomers, McIntosh added. (Make sure to observe proper eye safety during the eclipse.)

Because millions of people will be rushing to the small band of totality, however, the Department of Transportation has a special website available for the best routes. That's something people should check ahead of eclipse day, said Madhulika "Lika" Guhathakurta, the NASA lead scientist for the 2017 eclipse. "Traffic is going to be a nightmare," she said.

The eclipse is also well-timed, as the science community gears up for some major science projects that will focus on the sun. The Parker Solar Plus Probe will launch in 2018 to provide an unprecedented close-up view of the sun's corona, its superhot outer atmosphere. And in 2020, the Daniel K. Inouye Solar Telescope will act like a "microscope of the sun," as the 4-meter telescope begins gathering high-resolution imagery of Earth's closest stellar neighbor.

The science of totality

Astronomers can easily create an artificial eclipse for a particular observer using a device called a coronagraph, which blocks most of the sun except for its corona, its superheated outer atmosphere. Scientists want to study this feature of the star to better understand how energy is transmitted from the sun into space.

The corona "is a fairly blustery environment," McIntosh said, pointing out that the Earth is affected by the "space weather" that the corona's changes generate. The strongest solar flares can induce outages in satellites and power lines, which is another reason NASA and other organizations are interested in learning about the connection between the sun and the Earth's environment, he said.

The moon will provide an advantage, however, over a coronagraph when the eclipse occurs, the researchers said. The moon is 400 times smaller than the sun and, coincidentally, about 400 times closer to Earth — meaning it can cover the surface of the sun perfectly if the two bodies are aligned. A coronagraph, however, needs to be a bit larger than the sun's surface to avoid damage to the telescope.

"The moon is a perfect occulter. It blocks the surface of the sun just perfectly, so you can see very low into the solar atmosphere," said Carrie Black, the NSF's associate program director in the Division of Atmospheric and Geospace Sciences.

In particular, scientists will be interested in studying the "low corona," where most of the sun's activity is generated. Black said this zone — which is also where space weather originates — is of particular interest to the federal government, which is "investing a lot of money and organizing folks" to protect communications links and the power grid from space weather event.

Additional information about the sun's behavior comes from NASA's missions across the solar system, said Guhathakurta. NASA's many orbital missions at Mars and the New Horizons mission that flew by Pluto in 2015, for instance, can provide a new perspective because they can measure how its particles have changed energy or direction as they travel further out than Earth. This provides additional information to help forecast the sun's activity, Guhathakurta said.

Incidentally, the moon's topography will also influence which regions on the Earth experience totality during the eclipse, as the moon is not a flat surface; it is full of craters and mountains that affect the shadow passing across the Earth's surface. Data from NASA's Lunar Reconnaissance Orbiter is available to help people predict where they should be standing in the United States to get the best view.

Science projects

Here is a partial list of science observations going on (a full list from today's discussion is at https://www2.hao.ucar.edu/eclipse-science-showcase-attendees-experiments):

• Solar-Eclipse Induced Changes in the Ionosphere Over the Continental U.S. (led by Phil Erickson and Nancy Wolfe Kotary of the Massachusetts Institute of Technology and Haystack Observatory): This will look at the electrically charged region of the sun's atmosphere, which is in part affected by sunlight. During an eclipse, cold spots can cause ionospheric disturbances that ripple across the atmosphere. The team will study these disturbances across the United States using a huge network of more than 6,000 sensors on the Earth, as well as NASA's space-based Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) mission.
• EclipseMob: Crowdsourcing for Radio Propagation in the Ionosphere (a National Science Foundation project led by Jill Nelson of George Mason University): This will measure the ionosphere's response to low-frequency radio waves to better understand this region of the atmosphere, especially how the ionosphere can block low-frequency radio broadcasts. Using two transmitters that probe the ionosphere, students and the public will operate receivers and attempt to receive the data at certain frequencies.
• Chasing the 2017 Eclipse (led by Amir Caspi of the Southwest Research Institute): Two NASA WB-57 airplanes (flying from NASA's Johnson Space Center in Houston) will observe the sun and Mercury during the total solar eclipse, in both visible and infrared light. These aircraft will operate at 50,000 feet (15,000 m) of altitude and provide about 8 minutes of data of totality, nearly triple of what is available at ground level. Because the planes fly above 90 percent of the Earth's atmosphere, they will provide accurate measurements of the solar corona to see how energy propagates through the sun.

There also are crowdsourcing projects available, such as:

• Eclipse Megamovie: This will collect images from more than 1,000 volunteer photographers and amateur astronomers (and anyone else who is interested) to make a view of the total eclipse during its journey across the United States.
• Citizen CATE (Continental-America Telescopic Eclipse): This will take images of the inner solar corona, using 60 telescopes used by high schools, universities and citizen scientists. The goal is to get high-resolution imagery of the corona for 90 minutes.
• iNaturalist (California Academy of Sciences): This iTunes app will let people record the observations of organisms at their eclipse-watching locations. The academy suggests people record observations 30 minutes before totality, during totality and 30 minutes after totality.

Editor's note: Space.com has teamed up with Simulation Curriculum to offer this awesome Eclipse Safari app to help you enjoy your eclipse experience. The free app is available for Apple and Android, and you can view it on the web.

Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

Final New Moon Sunday Starts the Countdown to the Great American Eclipse

Final New Moon Sunday Starts the Countdown to the Great American Eclipse:

A sketch by Spanish astronomer José Joaquin de Ferrer shows the sun's corona extending outward during a total solar eclipse June 16, 1806.

Credit: José Joaquin de Ferrer

It seems that everyone is eagerly awaiting the shady drama that will be enacted in the skies over North America on Aug. 21. It is a play whose script was written eons ago: On that third Monday in August, the celestial wanderings of the sun, Earth and moon will cause our natural satellite to pass directly in front of the sun, resulting in a total eclipse on Aug. 21.

The narrow band of totality, averaging some 70 miles (113 kilometers) wide and stretching about 2,500 miles (4,023 km) from the Pacific coast of Oregon to the Atlantic coast of South Carolina, will provide a spectacle that has not been seen from any part of the contiguous United States in nearly 40 years.

To say that this has been an eagerly awaited astronomical event is an understatement. [The Best ISO-Certified Gear to See the 2017 Solar Eclipse]

Decades of anticipation

On Aug. 31, 1932, the New York Times ran a headline stating that a total solar eclipse that was to sweep across New England that day would be the last "really good" eclipse for the United States (from a logistical standpoint) until 2017.

Samuel Alfred Mitchell, professor of astronomy at the University of Virginia, was quoted as saying:

"It thus appears that after our eclipse of 1932 has passed into memory there will not be an opportunity to view a total eclipse of the sun from the continent of the United States, under conditions that are really favorable and promise scientific success until August 21, 2017; 85 years hence."

On March 7, 1970, during a telecast of a solar eclipse from Valdosta, Georgia, over the CBS Television Network, the late Charles Kuralt asked Kenneth Franklin of New York's Hayden Planetarium about the next total eclipse that would be accessible to folks "down South." Franklin then mentioned an eclipse that was still far in future: "The next eclipse that will pass across this nation and go out along the Carolinas will be in the year 2017." Noted Kuralt: "That's a pretty long time (47 years) to wait."

"Well," countered Franklin, "unfortunately, that's the way of the world."

Final countdown

It's difficult to say exactly when most people started counting down to this upcoming eclipse, but you might say that we could start an "official" or "final" countdown this weekend — on Sunday (July 23) at 5:46 a.m. EDT. That will be the moment of the new moon, and it will also be the last new moon before next month's solar eclipse.

On Sunday morning, the moon will pass in close proximity to the sun but will go completely unseen. At its closest, it will be situated 2.8-degrees south of the sun, or about 5.5 moon widths below the solar disk; a complete miss, so no eclipse of the sun at least for this month. Like a celestial clock, the moon will continue to move in its orbit around the Earth, on its way to keeping its long-awaited rendezvous with the sun in late August. [Total Solar Eclipse 2017: When, Where and How to See It (Safely)]

When the moon and sun cross paths

The interval from one new moon to the next is referred to as a "synodic" month, derived from the Late Latin word synodus, which means "meeting."

For indeed, at new moon, the moon "meets" the sun.

Next month, when the moon comes around to the sun's position once again, it will be near a point in space (called a "node"), where the moon can cross paths with the sun as seen from our earthly perspective, producing an eclipse of the sun.

Or as astronomer Leslie Peltier noted in his popular autobiography, "Starlight Nights" (Harper & Row, 1965): "Only during an eclipse of the sun can we note the instant when the old moon, moving eastward, crosses the median line of the sun and becomes a fresh new moon just starting out on another monthly lifetime."

Discrepancy in timing? 

But wait a minute. That next new moon will come on Aug. 21 at 2:30 p.m. EDT. That's almost 29.5 days after this Sunday's new moon. But it takes only 27.3 days for the moon to make one revolution around the Earth.

So where did the extra 2.2 days come from?

It may surprise you that there is more than one type of lunar months. In addition to the synodic month, there is also the sidereal month. If we were to align the position of the moon with a particular fixed star in the sky, it would take the moon about 27.3 days to return to a position where the moon is once again aligned with that star. And the moon will have also made one complete circuit in its orbit around the Earth in that same interval.

But if we note when the moon is most closely aligned with the sun, and then follow the moon for 27.3 days until it reaches that exact point in the sky again, the sun would no longer be there.

In fact, the sun's position would have shifted approximately 30 degrees farther to the east compared with the moon's position. So, in order to catch up with the sun in our sky, the moon will have to travel another two days to reach it. [Here Is NASA's Advice for Watching the 2017 Solar Eclipse]

The reason that the sun's position shifts to the east is due to Earth revolving around the sun. As a result, the sun's position in the sky is not fixed like the stars, but changes; it appears from our earthly vantage point to move eastward against the background stars by about 30 degrees each month. Think of a circle of 360 degrees and then divide that 360 by 12 (the number of months). We would get 30. (Of course, Earth's orbit is not a perfect circle and we take about 365.2422 days to go around the sun, compared to 360, but you get the general idea.)

And that's why even though it takes the moon just over 27 days to circle our Earth, it takes just over two additional days to go from one new moon to the next.

Meanwhile, remember the day this weekend (Sunday) and the time (5:46 a.m. EDT) marking the moment of the July new moon. When the moon cycles around the sky and turns new again one synodic month from now, on Aug. 21, the long-awaited "Great American Eclipse" will finally take place.

Editor's note: Space.com has teamed up with Simulation Curriculum to offer this awesome Eclipse Safari app to help you enjoy your eclipse experience. The free app is available for Apple and Android, and you can view it on the web.

Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, the Farmers' Almanac and other publications, and he is also an on-camera meteorologist for Fios1 News in Rye Brook, New York. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

'Stargate' Franchise Is Coming Back with 'Stargate Origins'

'Stargate' Franchise Is Coming Back with 'Stargate Origins':

"Stargate Origins," a 10-episode prequel series to the Stargate science fiction franchise, will debut on MGM's Stargate Command digital streaming service launching in Fall 2017.

Credit: Stargate Origins/MGM

Fans of "Stargate," rejoice! The science fiction franchise is getting a revival with "Stargate Origins," a new digital series that will serve as a prequel to the existing Stargate universe, which celebrates the 20th anniversary of its TV debut this year.

MGM announced the new Stargate TV series at San Diego Comic-Con, debuting a teaser trailer on Friday (July 21) for new show. The series will follow the character of Catherine Langdon during the early years of the titular Stargate's discovery in 1928. It will be a 10-episode series available on Stargate Command, a digital streaming site MGM will be launching this fall. So Stargate fans will likely have to sign up for the streaming service to see the new show, much like how CBS's digital streaming service CBS All Access will host the upcoming "Star Trek: Discovery" series. Get full San Diego Comic-Con 2017 coverage from Newsarama, Space.com's sister site, this weekend.

"'Stargate Origins' will explore a brand new chapter in Catherine Langford’s early history surrounding the extraordinary portal," MGM representatives said in July 20 statement. "Young Catherine embarks on an unexpected adventure to unlock the mystery of what lies beyond the Stargate in order to save Earth from unimaginable darkness."

MGM representatives said that Stargate Command will offer fans "exclusive access to a variety of Stargte assets and content from the franchise's nearly 25-year history." The franshise began with the 1994 feature film "Stargate" and debuted on television with the series "Stargate: SG-1." [Comic-Con 2017: A Space Fan's Guide]

"We've been eager to revisit the Stargate franchise, and create an all-new story that honors the founding mythos and gives loyal fans more mystery and adventure," said Kevin Conroy, President of Digital & New Platforms at MGM in the statement. "We view 'Stargate Origins' as a thank you to fans who have been keeping the spirit of the franchise alive for nearly 25 years. With the increasing popularity of digitally native content that can be streamed to any device, MGM is committed to the production of premium linear mid-form content and are proud to launch with 'Stargate Origins.'"

Email Tariq Malik at tmalik@space.com or follow him @tariqjmalik and Google+. Follow us @Spacedotcom, Facebook and Google+. 

Syfy's 'Krypton' Has a Time Travel DC Twist ... and Adam Strange & Brainiac

Syfy's 'Krypton' Has a Time Travel DC Twist ... and Adam Strange & Brainiac:

Syfy is bringing Superman's homeworld to life in the new TV series "Krypton" airing in 2018.

Credit: Syfy

Updated July 22, 2017 at 5:06 p.m. ET: More information - and more twists - have been revealed at Comic-Con about Syfy's "Krypton."

"It's a show that, although it takes place centuries ago on Krypton about the House of El, it's about a conspiracy from the present that has traveled back in time to to Krypton to prevent Superman's legacy from ever happening," Johns said at the show's panel (via The Hollywood Reporter). The 2018 show will start in the present as a group of DC villains jump back in time in an attempt to prevent the creation of Superman. And two heroes go back into the past to stop them: Adam Strange and Hawkwoman.

The 2018 show will start in the present as a group of DC villains jump back in time in an attempt to prevent the creation of Superman. And two heroes go back into the past to stop them: Adam Strange and Hawkwoman.

"Adam Strange and Hawkwoman come to Krypton trying to stop the conspiracy and save Superman's legacy," Johns continued. "Doomsday will be in the show. Brainiac is long overdue to be on screen like that."

Johns stated that "Krypton" will be seperate from the DCEU and other DC TV shows - that's despite original show co-creator David S. Goyer saying several years ago it would be connected to Man of Steel.

The showrunners said they knew that a show set entirely in the past would be unteniable for viewers, and came up with these twists.

"It changes the stakes of the show completely. ... It's not a look backwards. It's quite unique," said co-showrunner Cameron Welsh. "It allows us to deepen and expand upon the known mythology."

Johns then recited Adam's first lines from the show - seemingly from memory: "'I'm from a planet called Earth, my name is Adam Strange, I come from a time long after this and I need you to help me save the legacy of your grandson."

Johns said that in addition to those mentioned, other classic DC characters would appear later in Krypton's run.

"Krypton" will premiere in 2018 on Syfy.

Get full San Diego Comic-Con 2017 coverage from Newsarama, Space.com's sister site, this weekend.

Originally published on our sister site Newsarama.

Spock Has a Sister .. No, Really, and the New 'Star Trek: Discovery' Trailer

Spock Has a Sister .. No, Really, and the New 'Star Trek: Discovery' Trailer:

Sonequa Martin-Green portrays the lead role of Michael Burnham in "Star Trek: Discovery," which premieres Sept. 24, 2017.

Credit: CBS

Among the reveals Saturday at the "Star Trek: Discovery" panel at San Diego Comic-Con is that lead character Micheal Burnham (Sonequa Martin-Green) is the biological daughter of Spock's mother Amanda , and Spock's father Sarek is her surrogate father.

The character was also raised on Vulcan.

As to how the show is going to thread the needle of introducing a heretofore unrevealed major character in Star Trek canon, Executive Producer Alex Kurtzman told the Comic-Con audience, "We're aware. You'll see where it's going, but we are staying consistent with canon."

And here is the new trailer:

Watch the explosive trailer for the next chapter of the Star Trek franchise. #StarTrekDiscovery premieres Sept 24. https://t.co/f8pFoW6oyS pic.twitter.com/GxojITSRNz

— Star Trek: Discovery (@startrekcbs) July 22, 2017

"Star Trek: Discovery" premieres Sept. 24 on CBS before moving to the CBS All Access app, which requires a paid subscription, for the remainder of the first season.

Get full San Diego Comic-Con 2017 coverage from Newsarama, Space.com's sister site, this weekend.

Originally published on our sister site Newsarama.

Phobos: Moon over Mars

Phobos: Moon over Mars:

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2017 July 21

Phobos: Moon over Mars

Image Credit: NASA, ESA, Zolt Levay (STScI) - Acknowledgment: J.Bell (ASU) and M.Wolff (SSI)


Explanation: A tiny moon with a scary name, Phobos emerges from behind the Red Planet in this timelapse sequence from the Earth-orbiting Hubble Space Telescope. Over 22 minutes the 13 separate exposures were captured near the 2016 closest approach of Mars to planet Earth. Martians have to look to the west to watch Phobos rise, though. The small moon is closer to its parent planet than any other moon in the Solar System, about 3,700 miles (6,000 kilometers) above the Martian surface. It completes one orbit in just 7 hours and 39 minutes. That's faster than a Mars rotation, which corresponds to about 24 hours and 40 minutes. So on Mars, Phobos can be seen to rise above the western horizon 3 times a day. Still, Phobos is doomed.

Tomorrow's picture: to catch some sun

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World's 1st Laser Weapon Is Ready to Blast Rogue Drones

World's 1st Laser Weapon Is Ready to Blast Rogue Drones:

The newly developed Laser Weapon System (LaWS) is situated on the USS Ponce, which is deployed to the Persian Gulf.

Credit: John F. Williams/US Navy

The world's first laser weapon — one that can "kill" threatening, airborne drones — is ready for action, according to news sources.

The laser, known as the Laser Weapons System (LaWS), may seem as though it were pulled straight from a James Bond movie, but it's entirely functional and can shoot with stunning accuracy, the U.S. Navy told CNN. The LaWS is currently deployed aboard the USS Ponce, an amphibious transport ship, in the Persian Gulf.

"Operationally, it works just like a laser pointer," Lt. Cale Hughes, a LaWS officer, told CNN. "There's a chamber inside with special materials that release photons." [7 Technologies That Transformed Warfare]

The LaWS laser beam is completely silent and invisible. It's also fast: The laser travels at the speed of light (186,000 miles per second, or about 300,000 kilometers per second), meaning it's about 50,000 times the speed of an incoming intercontinental ballistic missile, such as the one North Korea is testing, the Navy told CNN.

The $40 million system requires a team of three to operate it and a small generator to power its electricity supply, according to the Navy.

However, each blast is relatively cheap. "It's about a dollar a shot," Hughes told CNN.

In addition to being able to take down threats in the air, the LaWS can hit and disable objects in the water. The laser's accurate blasts, heated to thousands of degrees, might even mean fewer casualties in combat, Inez Kelly, a U.S. Naval Forces Central Command science adviser, told CNN.

For instance, if the laser is aimed at an enemy boat, operatives can "take out exactly the engine, and not necessarily damage anything else," Kelly said. "That type of precision weapon work is something that you don't really get with conventional weapons, because there tends to be more collateral damage."

Under Geneva Convention rules, armed forces are not allowed to use laser weapons directly against people, reported Optics.org, a site that tracks the photonics industry. The U.S. will abide by that protocol, Rear Adm. Matthew Klunder, chief of naval research, said in 2014 at a news conference in Washington, D.C., according to Optics.org.

The U.S. Navy is already developing second-generation systems that might be able to target threats other than drones and water vessels. These missions are classified, but when asked whether the LaWS could shoot and destroy missiles, USS Ponce Capt. Christopher Wells said "maybe" and smiled, according to CNN.

Original article on Live Science.

Liftoff? Icy Jets of Saturn Moon Enceladus Fly in NASA Photo

Liftoff? Icy Jets of Saturn Moon Enceladus Fly in NASA Photo:

Saturn's moon Enceladus releases jets of water ice as imaged by the Cassini spacecraft in April. The moon shines in reflected Saturn light, while the jets are backlit by the sun.

Credit: NASA/JPL-Caltech/Space Science Institute

A photo of Saturn's moon Enceladus looks poised for liftoff as jets fly from its southern hemisphere.

While Enceladus can't fly — at least outside of its ordinary orbit around the ringed planet — its remarkable icy jets intrigue scientists because they hint at a subsurface ocean that could support life.

The photo, taken by the Cassini spacecraft, spotlights the moon's Saturn-facing hemisphere, which is 313 miles across (504 km), according to NASA's image caption. The jets are backlit by sunlight, while the front shines with light reflected back from Saturn. Cassini was 502,000 miles (808,000 km) from Enceladus when it captured the visible-light image with its narrow-angle camera on April 13, and the image shows 3 miles (5 km) per pixel.

Enceladus' fierce jets emerge from a series of ridges in its southern hemisphere nicknamed "tiger stripes." Cassini first spotted the jets in 2005, and dove through the plumes multiple times; in 2015, it passed within 30 miles (50 km) of the moon's surface while sampling their composition. Data from that flyby suggested that its subsurface ocean might have enough energy, suggested by the existence of molecular hydrogen, to host life similar to microbes on Earth. Besides water ice, the plumes contain traces of methane, ammonia, carbon monoxide, carbon dioxide, salts and simple organic molecules.

Cassini is a collaboration among NASA, the European Space Agency and the Italian Space Agency, and it has orbited Saturn since 2004. The probe is in the Grand Finale phase of its mission, as it makes close flybys between Saturn and its rings before plunging down into the planet's atmosphere Sept. 15. That dive is partially motivated by a desire to protect the little icy moon — as Cassini ran out of fuel, its orbit could have become unstable and led to it crashing and contaminating moons in Saturn's neighborhood.

Email Sarah Lewin at slewin@space.com or follow her @SarahExplains. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com. 

Future Space Colony? Maybe We Should Look Beyond Mars to Saturn's Titan Moon

Future Space Colony? Maybe We Should Look Beyond Mars to Saturn's Titan Moon:

NASA's Cassini spacecraft, Saturn, and Titan, Saturn's largest moon.

Credit: Cassini Model: Brian Kumanchik, Christian Lopez. NASA/JPL-Caltech. Migrated to Maya & materials updated by Kevin M. Gill

NASA and Elon Musk’s SpaceX are focused on getting astronauts to Mars and even one day establishing a colony on the Red Planet — but what if their attention is better directed elsewhere? A new paper in the Journal of Astrobiology & Outreach suggests that humans should instead establish a colony on Titan, a soupy orange moon of Saturn that has been likened to an early Earth, and which may harbor signs of "life not as we know it."

"In many respects, Saturn's largest moon, Titan, is one of the most Earth-like worlds we have found to date," NASA says on its website. "With its thick atmosphere and organic-rich chemistry, Titan resembles a frozen version of Earth, several billion years ago, before life began pumping oxygen into our atmosphere."

To be clear, Titan could have microbes — or, at the least, chemistry that resembles prebiotic life — but it is no Earth. The moon is perpetually covered in an orange cloud, and its atmosphere is not human-friendly. But Titan's gravity is walkable (14 percent that of Earth), radiation on the surface is less than on Mars due to its thick clouds, and it offers various sources from which visitors might generate energy.

As the paper's author, Amanda Hendrix, pointed out in a previous book that she co-authored, Beyond Earth: Our Path to a New Home in the Planets, Titan has massive deposits of hydrocarbons — compounds generally associated with petroleum and gas. Data from NASA's Cassini probe has shown that Titan has hundreds of times more liquid hydrocarbons than all of the known oil and natural gas reserves on Earth.

A simulation of the view from the ground on Titan.

Credit: Kevin M. Gill


Beyond Earth points out that people on Titan could get energy from these compounds if they use a separate combustion source that helps circumvent that fact that there's no oxygen in the moon’s atmosphere. But Hendrix's new research also discusses other ways of generating chemical energy, such as treating acetylene (an abundant compound) with hydrogen.

"In this paper, I wanted to dig into the chemical energy options a bit deeper and also look into alternative energy possibilities," said Hendrix, a staff scientist at the non-profit Planetary Science Institute. "My co-author, Yuk Yung, and I looked at chemical, nuclear, geothermal, solar, hydropower, and wind power options at Titan. The paper is designed to be a high-level first look at some of these topics."

RELATED: Saturn's Titan Moon May Offer a Glimpse of Life as We Don't Know It

While Hendrix said it's possible to generate such energy using technology that we have available today, she noted that there are ways that we could get even more out of Titan’s environment with the proper study. For example, more solar power would be generated if we learned about the capabilities of different photovoltaic cell materials — and most importantly, how they would behave on Titan.

Hydro power would require better mapping of Titan's abundant lake regions, including their topography and their flow rate. Even wind power would require some research into airborne wind turbines — but Hendrix said all of these options are promising.

"I imagine that, as here on Earth, a combination of energy sources will be useful on Titan," she said. "In particular, solar energy (using large arrays) and wind power (using airborne wind turbines) may be particularly effective."

RELATED: A City on Mars: Elon Musk Details SpaceX's Plan to Colonize the Red Planet

Delivered properly, the energy needs would be more than enough for a small outpost. Instead of just sending humans on a one-shot mission to look for life on the surface, for example, Hendrix envisions a future that could generate power for years. One scenario — solar arrays over 10 percent of Titan's surface area — would generate power needs of a population of roughly 300 million, equivalent to that of the United States.

"This is just an initial estimate, of course, but what we're talking about is something much larger than a short-term human science mission to Titan," Hendrix said.

With NASA's stated goal of sending humans to Mars by the 2030s, however, space agencies remain focused on Mars exploration. While the Cassini robotic mission at Saturn and its moons wraps up observations this September, NASA and the European Space Agency are planning even more missions to Mars in the coming years. Saturn doesn't really figure into the plans, although NASA is thinking about eventual missions to Uranus, Neptune, and Jupiter's moon Europa.

Originally published on Seeker.

A Huge Asteroid Hitting Mars 4 Billion Years Ago May Have Shaped the Red Planet

A Huge Asteroid Hitting Mars 4 Billion Years Ago May Have Shaped the Red Planet:

A composite pictures of (from left to right) Mars, Phobos, and Deimos. A giant impact could have formed these two small moons, according to a new paper.

Credit: NASA

The peculiar geological features on Mars have long puzzled astronomers and planetary scientists. The north of the planet is mostly smooth lowlands while the south is higher and full of craters, and the Red Planet’s interior has a striking abundance of rare metals.

Researchers have proposed various explanations for these elements, positing that they may have been shaped by such forces as ancient oceans, extraterrestrial plate tectonics, or a massive asteroid strike. The latter idea, known as the "single impact hypothesis," has picked up steam of late, and was just given a shot in the arm by a new paper that argues that the sculpting of Mars and its two small moons was largely determined by a huge impact early in the solar system's history.

In this scenario, a celestial body that was roughly the size of Ceres, a dwarf planet in the asteroid belt, collided with the Red Planet and tore away a part of its northern hemisphere, leaving behind large deposits of metallic elements. Additionally, debris from the asteroid circled the planet and eventually coalesced into Phobos and Deimos, the two tiny moons that orbit Mars — at least for now. (Scientists estimate that Phobos will either break up or slam into Mars in a few million years.)

RELATED: Mars May Have Been Born in the Asteroid Belt

"We showed in this paper — that from dynamics and from geochemistry — that we could explain these three unique features of Mars," said Stephen Mojzsis, a professor in the University of Colorado Boulder's department of geological sciences and a co-author of the paper, in a statement. "This solution is elegant, in the sense that it solves three interesting and outstanding problems about how Mars came to be."

The research, which Mojzsis produced in collaboration with Ramon Brasser, an astronomer at the Earth-Life Science Institute at the Tokyo Institute of Technology in Japan, was recently published in Geophysical Research Letters. It looked at Martian meteorite samples that landed on Earth. These samples had more rare metals (like iridium, osmium or platinum) than expected, hinting that Mars received a lot of impacts from small, rocky asteroids that carried these elements with them.

The scientists estimated that these rare metals account for about 0.8% of the mass of Mars.

RELATED: NASA's Curiosity Rover Traces Ancient Environmental Changes on Mars

They then ran simulations with asteroids of various sizes to determine what size would best fit the Martian geology. The answer was a huge asteroid about 745 miles across (1,200 kilometers) — nearly the length of the state of California. The simulations suggest this behemoth slammed into Mars about 4.43 billion years ago, just 700 million years after the solar system was formed. Several smaller impacts occurred in the eons that followed.

The researchers theorize that after the big impact took place, there were distinct areas of asteroid material and Red Planet rock on the surface. Over time, however, erosion, wind, and other processes on the surface swept the two reservoirs together in a mixture.

Mojzsis and Brasser next plan to use UC Boulder's Martian meteorite archives to see how the composition of these meteorites differs or remains the same, depending on how old the meteorites are.

Originally published on Seeker.

In 'Valerian,' International Space Station Evolves into Interstellar Metropolis

In 'Valerian,' International Space Station Evolves into Interstellar Metropolis:

The city of Alpha in Luc Besson's latest fantasy film, "Valerian and the City of a Thousand Planets," shares a few similarities to the existing International Space Station, which is highlighted in the opening scene of the movie.

Credit: STX Films and Europacorp

In the new adventure movie "Valerian and the City of a Thousand Planets," directed by Luc Besson, the title city of Alpha has a present-day origin: the International Space Station.

The opening of "Valerian" — a film inspired by the popular French comic series "'Valérian et Laureline," created by Pierre Christin and Jean-Claude Mézières — has a scene that showcases the International Space Station (ISS) as it grows into a galactic United Nations, hosting meet-and-greets with representatives from Earth and, later, aliens. It grows physically, too, until it is large enough that it needs to be moved out of low-Earth orbit. [Read our full "Valerian" review!]

The fictional metropolis Alpha was inspired by Point City, which was first written about in the sixth volume of the "Valerian and Laureline" graphic novel series, entitled "Ambassador of the Shadows."

Credit: Dargaud


The ISS' evolution is a plausible one: The station has a history of bringing cultures together to build itself and to exchange ideas. In "Valerian," the first greeting in the montage takes place in the not-too-distant year 2020, where two human astronauts are shown embracing, and as we advance in time, we see increasingly strange aliens introduce themselves to humans on board the station.

Certainly, the international crews that have continuously occupied the existing ISS since 2000 would have milder reactions to meeting foreign astronauts than hypothetically meeting alien life-forms. However, the ISS was nevertheless groundbreaking in its ability to unite five space agencies to expand scientific research possibilities and to mend older nationalistic divisions. Many of the space programs involved with the station — NASA (United States), Roscosmos (Russia), CSA (Canada), JAXA (Japan), ESA (Europe) — include countries that have warred with one another in the last century.

This image is a side-by-side view of early space station concepts in fact and fiction. In the decade following these illustrations, the "Valerian and Laureline" comic was written, later inspiring director Luc Besson to create the 2017 "Valerian" film.

Credit: Karl Tate, Space.com


Early concepts for the ISS had the space station taking the shape of a giant wheel. Wernher von Braun developed an ISS station concept in 1952 that was round in order to provide simulated gravity through rotation, with a capacity to house dozens of scientists, according this Space.com infographic.

Science-fiction storytellers were clearly inspired by these concepts, and a few years later, in 1968, Stanley Kubrick's film "2001: A Space Odyssey" developed a model for a space station that was in a similar wheel shape. The year before, 1967, the first issue of "Valerian and Laureline" was published by Dargaud, according to "Valerian" film representatives. Point Central, a vast space station that lies at the crossroads of space that inspired Alpha in the film adaptation, appeared a few years later, in the 1975 comic "Valerian Vol 6: Ambassador of the Shadows."

Right now, NASA and U.S. officials have only promised to fund the ISS through 2024, so it's uncertain what the future will hold for the orbiting lab. But as crews from around the world work together to research and live in space, science-fiction writers have inspiration to continue writing tales of the ISS expanding someday into that kind of vibrant metropolis.

Mission specialists Lopez-Alegria and Herrington working on a newly installed Port One (P1) truss on the International Space Station in 2002.

Credit: NASA


Follow Doris Elin Salazar on Twitter @salazar_elin. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

Old NASA Computers, Tapes Found in Dead Man's Basement

Old NASA Computers, Tapes Found in Dead Man's Basement:

Artist's illustration of NASA's Pioneer 10 spacecraft approaching Jupiter in late 1973.

Credit: NASA

Two huge, Apollo-era NASA computers and more than 300 data-recording tapes were found in the Pittsburgh basement of a dead engineer in late 2015, according to media reports.

In November 2015, a scrap dealer was invited to clean out the basement of the recently deceased IBM engineer, who did some work for NASA at the height of the Space Race, Ars Technica reported. The dealer found about 325 magnetic data tapes and the two giant computers, both of which were marked "NASA Property."

The scrap dealer contacted NASA to inform the agency of the find, and NASA's Office of the Inspector General (OIG) performed an investigation. Ars Technica obtained the OIG's report via a Freedom of Information Act request.

"Please tell NASA these items were not stolen," the engineer's heir told the scrap dealer, according to the OIG report. "They belonged to IBM Allegheny Center, Pittsburgh, PA 15212. During the 1968-1972 time frame, IBM was getting rid of the items, so [the engineer] asked if he could have them and was told he could have them."

The relevant names have been redacted in the OIG report.

NASA officials told the deceased engineer's family that the agency did not need the computers back. After further investigation, an agency archivist determined that 93 of the tapes contained data from Pioneer 10 or Pioneer 11, flyby missions to Jupiter and Saturn that launched in the early 1970s.

A few of the other tapes recorded data from the Pioneer 8, Pioneer 9, Helios 1 and Intelsat IV missions, but most of the recordings — about 215 of them — could not be identified. The archivist recommended that all the tapes — which were moldy and in generally poor condition — be destroyed, because they didn't contain anything of historical significance.

You can read the NASA OIG report here and the full story at Ars Technica here.

Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us @Spacedotcom, Facebook or Google+. Originally published on Space.com.

Advanced Civilizations Could Build a Galactic Internet with Planetary Transits

Advanced Civilizations Could Build a Galactic Internet with Planetary Transits:

Decades after Enrico Fermi’s uttered his famous words – “Where is everybody?” – the Paradox that bears his name still haunts us. Despite repeated attempts to locate radio signals coming from space and our ongoing efforts to find visible indications of alien civilizations in distant star systems, the search extra-terrestrial intelligence (SETI) has yet to produce anything substantive.

But as history has taught us, failure has a way of stimulated new and interesting ideas. For example, in a recently-published paper, Dr. Duncan H. Forgan of St. Andrews University proposed that extra-terrestrial civilizations could be communicating with each other by creating artificial transits of their respective stars. This sort of “galactic internet” could be how advanced species are attempting to signal us right now.

Forgan’s paper, “Exoplanet Transits as the Foundation of an Interstellar Communications Network“, was recently published online. In addition to being a research fellow at the School of Physics and Astronomy and the Scottish Universities Physics Alliance at the University of St Andrews (Scotland’s oldest academic institution), he is also a member of the St Andrews Center for Exoplanet Science.



The paper begins by addressing the two fundamental problems associated with interstellar communication – timing and energy consumption. When it comes to things like radio transmissions, the amount of energy that would be needed to transmit a coherent message over interstellar distances is prohibitive. Optical communications (i.e. lasers) need less energy, but spotting them would require incredibly precise timing.

As such, neither method would be particularly reliable for establishing an interstellar communications system. Taking a cue from humanity’s recent exoplanet-hunting efforts, Forgan argues that a method where transits in front of a stars are a basis of communication would solve both problems. The reason for this is largely due to the fact that the Transit Method is currently one of the most popular and reliable ways of detecting exoplanets.

By monitoring a star for periodic dips in brightness, which are caused by a planet or object passing between the observer and the star, astronomers are able to determine if the star has a system of planets. The method is also useful for determining the presence and composition of atmospheres around exoplanet. As Forgan indicates in the paper, this method could therefore be used as a means of signalling other civilizations:

“An ETI ’A’ can communicate with ETI ’B’ if B is observing transiting planets in A’s star system, either by building structures to produce artificial transits observable by B, or by emitting signals at B during transit, at significantly lower energy consumption than typical electromagnetic transmission schemes.”

The Milky Way’s habitable zone. Credit: NASA/Caltech

In short, Forgan argued that within the Galactic Habitable Zone (GHZ) – the region of the Milky Way in which life is most likely develop – species may find that the best way to communicate with each other is by creating artificial megastructures to transit their star. These transits, which other civilizations will be looking for (looking for exoplanets, like us!) will lead them to conclude that an advanced civilization exists in another star system.

He even offers estimates on how often such transmissions could be made. As he put it:

“A message with a path of 20 kpc (the diameter of the GHZ) has a total travel time at lightspeed of just under 0.06 Myr. If we assume a relatively short timescale on which both ETIs remain in the transit zone of 100,000 years (which is approaching the timescale on which both secular evolution of planetary orbits and the star’s orbit become important), then a total of 30 exchanges can be made. This of course does not forbid a continuing conversation by other means.”

If this is starting to sound familiar, that’s probably because this is precisely what some theorists say is happening around KIC 8462852 (aka. Tabby’s Star). Back in May of 2015, astronomers noticed that the star had been undergoing considerable drops in brightness in the past few years. This behavior confounded natural explanations, which led some to argue that it could be the result of an alien megastructure passing in front of the star.

According to Forgan, such a possibility is hardly far-fetched, and would actually be a relatively economical means of communicating with other advanced species. Using graph theory, he estimated that civilizations within the GHZ could establish a fully connected network within a million years, where all civilizations are in communication with each other (either directly or via intermediate civilizations).

Artist’s concept of KIC 8462852, which has experienced unusual changes in luminosity over the past few years. Credit: NASA, JPL-Caltech

Not only would this network require far less energy to transmit data, but the range of any signal would be limited only by the extent of these civilizations themselves. Beyond saving energy and having greater range (assuming intermediate civilizations are able to pass messages along), this method presents other advantages. For one, a high level of technological sophistication would be required to pick up the transit of exoplanets.

In other words, civilizations would need to reach a certain level of development before they could hope to join the network. This would prevent any unfortunate “cultural contamination”, where less-advanced civilizations learned about the existence of aliens before they were ready. Second, once acquired, the transit network signals would be extremely predictable, with each transmission corresponding to a known orbital period.

That being said, there are some downsides that Forgan was sure to acknowledge. For starters, the periodicity of these signals would be a double edged sword, as signals could only be sent if and when the receiver begins to see the transit. And while a megastructure could be moved to alter the transit period, this poses problems in terms of synchronizing transmission and reception.

Addressing the limitations of the analysis, Forgan also acknowledges that the study relies on fixed stellar orbits. The orbits of stars are known to change over time, with stars passing in and out of the GHZ regularly on cosmic timescales. In addition, there is also the issue of how such a network would differ between denser regions in the galaxy – i.e. globular clusters – and areas populated by field stars. Binary stars are also not considered in the analysis.

Could alien megastructures be the key to interstellar communications? Credit: Kevin Gill

In addition, planetary orbits are known to change over time, due to perturbations caused by neighboring planets, companion stars, or close encounters with passing stars. As a result, the visibility of transiting planets can vary even more over cosmic timescales. Last, but not least, the study assumes that civilizations have a natural lifespan of about a billion years, which is not based in any concrete knowledge.

However, these considerations do not alter the overall conclusions reached by Forgan. Making allowances for the dynamic nature of stars and planets, and assuming that civilizations exist for only 1 million years, Forgan maintains that the creation of an interstellar network of this kind is still mathematically feasible. On top of that, an artificial object could continue to signal other species long after a civilization has gone extinct.

Addressing the Fermi Paradox, Forgan concludes that this sort of communication would take a long time to detect.As he summarizes in the paper (bold added for emphasis):

“I find that at any instant, only a few civilizations are correctly aligned to communicate via transits. However, we should expect the true network to be cumulative, where a “handshake” connection at any time guarantees connection in the future via e.g. electromagnetic signals. In all our simulations, the cumulative network connects all civilizations together in a complete network. If civilizations share knowledge of their network connections, the network can be fully complete on timescales of order a hundred thousand years. Once established, this network can connect any two civilizations either directly, or via intermediate civilizations, with a path much less than the dimensions of the GHZ.”

In short, the reason we haven’t heard from or found evidence of ETI could be an issue of timing. Or, it could be that we simply didn’t realize we were being communicated with. While such an analysis is subject to guess-work and perhaps a few anthropocentric assumptions, it is certainly fascinating because of the possibilities it presents. It also offers us a potential tool in the search for extra-terrestrial intelligence (SETI), one which we are already engaged in.

So many stars, so many planets. So many opportunities for connection! Credit: ESO/M. Kornmesser

And last, but not least, it offers a potential resolution to the Fermi Paradox, one which we may have already stumbled upon and are simply not yet aware of. For all we know, the observed drops in brightness coming from Tabby’s Star are evidence of an alien civilization (possibly an extinct one). Of course, the key word here is “perhaps”, as no evidence exists that could confirm this.

The possibilities raised by this paper are also exciting given that exoplanet-hunting is expected to ramp up in the coming years. With the deployment of next-generations missions like the James Webb Space Telescope and the Transiting Exoplanet Survey Satellite (TESS), we expect to be learning a great deal more about star systems both near and far.

Will we find more examples of unexplained drops in brightness? Who knows? The point is, if we do (and can’t find a natural cause for them) we have a possible explanation. Maybe its neighbors inviting us to “log on”!

Further Reading: arXiv

The post Advanced Civilizations Could Build a Galactic Internet with Planetary Transits appeared first on Universe Today.

Earth-Sized Planet Takes Just Four Hours to Orbit its Star

Earth-Sized Planet Takes Just Four Hours to Orbit its Star:

The Kepler space observatory has made some interesting finds since it began its mission back in March of 2009. Even after the mission suffered the loss of two reaction wheels, it has continued to make discoveries as part of its K2 mission. All told, the Kepler and K2 missions have detected a total of 5,106 planetary candidates, and confirmed the existence of 2,493 planets.

One of the latest finds made using Kepler is EPIC 228813918 b, a terrestrial (i.e. rocky) planet that orbits a red dwarf star some 264 to 355 light years from Earth. This discovery raises some interesting questions, as it is the second time that a planet with an ultra-short orbital period – it completes a single orbit in just 4 hours and 20 minutes – has been found orbiting a red dwarf star.

The study, which was recently published online, was conducted by an international team of scientists who hail from institutions ranging from the Massachusetts Institute of Technology (MIT), the California Institute of Technology (Caltech), the Tokyo Institute of Technology, and the Institute of Astrophysics of the Canary Islands (IAC) to observatories and universities from all around the world.

NASA’s Kepler space telescope was the first agency mission capable of detecting Earth-size planets. Credit: NASA/Wendy Stenzel

As the team indicated in their study, the detection of this exoplanet was made thanks to data collected by numerous instruments. This included spectrographic data from the 8.2-m Subaru telescope and the 10-m Keck I telescope (both of which are located on Mauna Kea, Hawaii) and the Nordic Optical Telescope (NOT) at the Roque de los Muchachos Observatory in La Palma, Spain.

This was combined with speckle imaging from the 3.5-m WIYN telescope at the Kitt Peak National Observatory in Arizona, photometry from the NASA’s K2 mission, and archival information of the star that goes back over 60 years. After eliminating any other possible explanations – such as an eclipsing binary (EB) – they not only confirmed the orbital period of the planet, but also provided constrains on its mass and size. As they wrote:

“Using a combination of archival images, AO imaging, RV measurements, and light curve modelling, we show that no plausible eclipsing binary scenario can explain the K2 light curve, and thus confirm the planetary nature of the system. The planet, whose radius we determine to be 0.89 ± 0.09 [Earth radii], and which must have a iron mass fraction greater than 0.45, orbits a star of mass 0.463 ± 0.052 M and radius 0.442 ± 0.044 R.”

This orbital period – four hours and 20 minutes – is the second shortest of any exoplanet discovered to date, being just 4 minutes longer than that of KOI 1843.03, which also orbits an M-type (red dwarf) star. It is also the latest in a long line of recently-discovered exoplanets that complete a single orbit of their stars in less than a day. Planets belonging to this group are known as ultra-short-period (USP) planets, of which Kepler has found a total of 106.

Archival images of the star EPIC 228813918, demonstrating its proper motion over nearly six decades – from (i) 1954, (ii) 1992, and (iii) 2012. Credit: Smith et al.

However, what is perhaps most surprising about this find is just how massive it is. Though they didn’t measure the planet’s mass directly, their constraints indicate that the exoplanet has an upper mass limit of 0.7 Jupiter masses – which works out to over 222 Earth masses. And yet, the planet manages to pack this gas giant-like mass into a radius that is 0.80 to 0.98 times that of Earth.

The reason for this, they indicate, has to do with the planet’s apparent composition, which is particularly metal-rich:

“This leads to a constraint on the composition, assuming an iron core and a silicate mantle. We determine the minimum iron mass fraction to be 0.525 ± 0.075 (cf. 0.7 for KOI 1843.03), which is greater than that of Earth, Venus or Mars, but smaller than that of Mercury (approximately 0.38, 0.35, 0.26, and 0.68, respectively; Reynolds & Summers 1969).”

Ultimately, the discovery of this planet is significant for a number of reasons. On the one hand, the team indicated that the constraints their study placed on the planet’s composition could prove useful in helping to understand how our own Solar planets came to be.

“Discovering and characterizing extreme systems, such as USP planets like EPIC 228813918 b, is important as they offer constraints for planet formation theories,” they conclude. “Furthermore, they allow us to begin to constrain their interior structure – and potentially that of longer-period planets too, if they are shown to be a single population of objects.”

An artist’s depiction of extra-solar planets transiting an M-type (red dwarf) star. Credit: NASA/ESA/STScl

On the other hand, the study raises some interesting questions about USP planets – for instance, why the two shortest-period planets were both found orbiting red dwarf stars. A possible explanations, they claim, is that short-period planets could have longer lifetimes around M-dwarfs since their orbital decay would likely be much slower. However, they are quick to caution against making any tentative conclusions before more research is conducted.

In the future, the team hopes to conduct measurements of the planet’s mass using the radial velocity method. This would likely involve a next-generation high-resolution spectrograph, like the Infrared Doppler (IFD) instrument or the CARMENES instrument – which are currently being built for the Subaru Telescope and the Calar Alto Observatory (respectively) to assist in the hunt for exoplanets around red dwarf stars.

One thing is clear though. This latest find is just another indication that red dwarf stars are where exoplanet-hunters will need to be focusing their efforts in the coming years and decades. These low mass, ultra-cool and low-luminosity stars are where some of the most interesting and extreme finds are being made. And what we stand to learn by studying them promises to be most profound!

Further Reading: arXiv

The post Earth-Sized Planet Takes Just Four Hours to Orbit its Star appeared first on Universe Today.

IC 1396: Emission Nebula in Cepheus

C 1396: Emission Nebula in Cepheus:

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2017 July 20

IC 1396: Emission Nebula in Cepheus

Image Credit & Copyright: César Blanco González


Explanation: Stunning emission nebula IC 1396 mixes glowing cosmic gas and dark dust clouds in the high and far off constellation of Cepheus. Energized by the bright central star seen here, this star forming region sprawls across hundreds of light-years, spanning over three degrees on the sky while nearly 3,000 light-years from planet Earth. Among the intriguing dark shapes within IC 1396, the winding Elephant's Trunk nebula lies just below center. Stars could still be forming inside the dark shapes by gravitational collapse. But as the denser clouds are eroded away by powerful stellar winds and radiation, any forming stars will ultimately be cutoff from the reservoir of star stuff. The gorgeous color view is a composition of image data from narrowband filters, mapping emission from the nebula's atomic oxygen, hydrogen, and sulfur into blue, green, and red hues.

Tomorrow's picture: moon with a scary name

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July 14 Solar Flare and a Coronal Mass Ejection

July 14 Solar Flare and a Coronal Mass Ejection: A medium-sized (M2) solar flare and a coronal mass ejection erupted from the same, large active region of the sun on July 14, 2017. The flare lasted almost two hours, quite a long duration. The coils arcing over this active region are particles spiraling along magnetic field lines.

Original enclosures: