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« Reply #30 on: Jul 08, 2015, 05:20 AM »

Start-up aims to offer on-demand meteor showers

July 7, 2015
Chuck Bednar for redOrbit.com – @BednarChuck

Ever wanted to see a meteor shower, but wish you could do it on your own schedule instead of having to wait until just the right moment? Scientists at a Japanese start-up could soon be able to accommodate you by making it so that shooting stars can rain down on-demand.

According to Space.com, officials at the company, ALE, said they possess a secret chemical formula that they hope to place into small, one-inch wide spheres and shoot from a satellite, thus creating artificial meteor showers anytime their paying customers want them to.

ALE is said to be teaming with scientists at several universities to produce their synthetic meteor showers, which will reportedly cost more than $8,000 per meteor to fire off. In addition, the ALE representatives said that the process is bright enough to be visible even in big cities or other areas with light pollution – as long as there’s clear weather that night. Lena Okajima, the company’s founder and CEO, told AFP that the meteor showers could be called off up to 100 minutes in advance in the case of bad weather.

Designed for entertainment, but still scientifically beneficial

Naturally-occurring meteor showers take place when space dust and debris travel through the Earth’s atmosphere, heating up along the way and often burning up completely before they can reach the ground, but the artificial meteors would be launched from a microsatellite some 20 inches (50 centimeters) across.

The launch satellite, which AFP reports is currently being developed by the company along with researchers from other groups, would orbit the planet from north to south, at altitudes of roughly 250 to 310 miles (400 to 500 km), for months at a time before it fell back to the Earth and burned up along the way. Its meteorites would be incinerated in the atmosphere, just like real ones.

ALE is not revealing the chemical composition of the formula it plans to use in the pellets, but the firm said that it is considering altering it to create streaks of different colors.

While Okajima said the main purpose of the artificial shooting stars was “entertainment,” Space.com said that they “could also be valuable to scientists.” Researchers explained that by analyzing the light of a meteor, they can learn about the temperature, density, and movement of the atmosphere at that altitude. However, real meteor showers are unpredictable, while ALE’s will occur at a predetermined time and place, making them easier to find and study.


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« Reply #31 on: Jul 08, 2015, 05:50 AM »

CS Monitor

How NASA telescope could reveal mysteries of supermassive black holes

NASA's NuSTAR telescope has spotted five previously undetected supermassive black holes, millions more could be lying in wait.

By Cristina Maza, Staff writer July 7, 2015   

It's hard to imagine that anything "supermassive" would be very good at hiding, but astronomers believe that there may be millions of supermassive black holes in the universe just waiting for the right tool to expose them.

The space agency's Nuclear Spectroscopic Telescope Array (NuSTAR) just may be that instrument.

“While hidden from view from most other telescopes, NuSTAR can spot [black holes] by detecting the highest-energy X-rays, which can penetrate through the enshrouding gas and dust,” NASA’s website outlines.

So far, NuSTAR has identified five previously undetected supermassive black holes while scouring nine separate galaxies. Researchers presented those findings Monday at the Royal Astronomical Society’s National Astronomy Meeting in Llandudno, Wales.

So what exactly is a supermassive black hole?

“Black holes come in several different varieties, all of which are characterized by a dense concentration of mass compressed into a tiny space and a gravitational force so powerful it keeps light from escaping,” the Monitor’s Noelle Swan reported in September, following the discovery of a supermassive black hole inside one of the smallest known dwarf galleries.

“The most widely understood black holes are known as stellar black holes and can contain 20 times the mass of the sun within a ball of space with a diameter of about 10 miles. Supermassive black holes can be as vast as the entire solar system and contain as much mass as found in 1 million suns combined,” she continued.

The discovery in September hinted at the potential existence of around twice as many black holes as astronomers had originally predicted. Meanwhile, the findings presented in Wales on Tuesday suggests that these additional black holes could be discovered and observed. 
Recommended: Are you a space whiz? Take our quiz!

"Thanks to NuSTAR, for the first time, we have been able to clearly identify these hidden monsters that are predicted to be there, but have previously been elusive because of their surrounding cocoons of material," George Lansbury, the lead author of the findings, said Tuesday.


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« Reply #32 on: Jul 08, 2015, 09:23 AM »

Exploring our moon today to learn more about Earth’s youth billions of years ago

The Conversation
08 Jul 2015 at 10:11 ET                   

The surface of the Earth preserves little or no information about its distant past. Constant tectonic activity has recycled Earth’s crust and shifted landmasses. Rainfall, wind, ice and snow have weathered away surface features over billions of years. Most of the craters formed by the impacts of asteroids and comets have been erased from the geologic record, with just over 100 known craters remaining on the continents.

But there is a place that we can go to learn more about the past of our own planet: the moon. In sharp contrast to Earth’s surface, that of the moon is covered with thousands of craters of all sizes, many of them produced shortly after the moon was born. The moon doesn’t have the winds, rivers or plate tectonics capable of erasing these marks of ancient impacts.

For that reason, the surface of the moon is like a window into the early history of our solar system. By studying the chemical composition of rocks and soil on our natural satellite, we could obtain a glimpse of the Earth’s own geological infancy – including the emergence of life.

Way back when

The Earth formed 4.54 billion years ago, after ancient asteroids known as planetesimals piled up into a single, planet-sized body as they orbited the sun. Scientists think the moon formed roughly 70 million years later, when a planet about the size of Mars collided with the young Earth. With the aid of sophisticated computer models, experts have shown that this huge collision created a donut-shaped envelope of molten rock and hot gas around the Earth. By calculating how this scorching disk would lose its heat, they’ve deduced that the moon condensed from all this hot material in less than 100 years.

Fast forward some 500 million years. Around this time, the giant planets Jupiter, Saturn, Uranus and Neptune likely underwent a rearrangement of their orbits around the sun, as a result of complex gravitational interactions with myriad planetesimals. This rearrangement sent many asteroids on a collision course with Earth. When they crashed into our planet, their impacts launched terrestrial fragments into Earth’s orbit. A very exciting possibility is that some of those Earth rocks might have landed on the moon.

If those pieces of Earth did make it to the moon, they’re probably still lying somewhere on the lunar surface. Some studies predict a large concentration of impacts near the moon’s poles. In some regions, there may be as much as a golf cart’s mass worth of terrestrial material spread over an area equivalent to 140 soccer fields. Whether this mass is in the form of rocks or tiny dust particles depends on, among other things, how hard Earth’s fragments hit the lunar ground.

Messages from Earth on the moon

Regardless of their size, terrestrial remnants could contain invaluable information about our planet’s early years. For example, those terrestrial meteorites may hold a record of the chemical composition of the Earth’s ancient mantle, the hot layer of rock between the crust and the core. Learning about the composition of the Earth billions of years ago would allow us to make comparisons with our present-day planet. With more historical data, we could infer how a habitable planet evolves over time, which would enable us to understand extrasolar planetary systems.

And since we’re talking about habitability, consider this: if there are terrestrial meteorites on the moon, they could potentially give us details about the conditions on Earth right before, or even during, the emergence of life. Stuff to look for on the rock samples blasted off Earth would be organic carbon, minerals gathered by microorganisms, or maybe even fossilized microbes.

Evidence of Earth’s enigmatic past may also be found on the moon in a more subtle way. Some researchers have suggested that ancient atmospheric gases from Earth could be trapped in the lunar soil. Right around the time when the young Earth and moon were heavily bombarded by asteroids, the moon was half as close to the Earth as it is now. It’s therefore possible that Earth’s atmosphere came into contact with the lunar surface.

To search for traces of earthly gases on the moon, the proponents of this idea suggest using well-known experimental techniques to detect the presence of helium, nitrogen and oxygen in lunar grains. The idea would be to measure how much of their various isotopes – the differing flavors of an element based on how many neutrons they have in the atomic nucleus – are present. Since the number of neutrons in isotopes changes at known rates, it’s possible to measure how much of one isotope there is in a grain in relation to its “parent” isotope. That would tell you how long those particular elements have been attached to the grains. If it turns out that the isotopes have been there for at least four billion years, there’s a good chance they came from Earth.

Detecting four-billion-year-old terrestrial oxygen on the moon would be another way to learn about the appearance of life, since atmospheric oxygen would probably have been produced by ancient photosynthetic organisms. Moreover, finding equally old nitrogen could mean that the early Earth did not have a magnetic field as it does today, because electrically charged nitrogen atoms from Earth’s atmosphere would not be capable of reaching the moon had there been a magnetic field.

Does the moon hold some of the early Earth’s secrets?

We are still a long way from obtaining a clear understanding of our home planet. But the possibility of lunar exploration by private ventures, in addition to that carried out by national space agencies, raises the prospects of mind-blowing discoveries that can shed light on Earth’s mysteries.

We may well end up repeating the words of Apollo 8 astronaut Bill Anders: “We came all this way to explore the moon, and the most important thing is that we discovered the Earth.”

By Augusto Carballido, Baylor University

Augusto Carballido is Assistant Research Professor at Baylor University.


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« Reply #33 on: Jul 09, 2015, 06:01 AM »

Saturn’s moon Enceladus may have weak interior

July 8, 2015
Chuck Bednar for redOrbit.com

Geysers of ice and water vapor emanating from the surface of Enceladus experience an unusual delay that could indicate that the sixth-largest moon of Saturn lacks a strong interior, researchers claim in a new study published this week in the journal Nature Geoscience.

According to Space.com, scientists believe that beneath the surface of this icy moon, there is an ocean of liquid water that could potentially harbor life. By studying its geysers, they hope to find out more detail about what the subterranean surface of Enceladus is really like.

In their study, a team of researchers from the US, France, and the Czech Republic explained that “eruptions of water vapor and ice emanate from warm tectonic ridges” at the moon’s south pole, and that observations in the visible and infrared spectra have revealed “an orbital modulation of the plume brightness,” suggesting that the eruptions are “influenced by tidal forces.”

However, that activity appeared to be experiencing a delay of several hours compared to what simple tidal models predicted. This prompted the authors to “simulate the viscoelastic tidal response of Enceladus with a full three-dimensional numerical model and show that the delay in eruption activity may be a natural consequence of the viscosity structure in the south-polar region and the size of the putative subsurface ocean.”

What lies beneath the surface

They compared plume brightness data to simulations of varying normal stress levels along faults, and found that the activity was reproduced in two different interior models: one involving a low-viscosity convective region above a polar sea along the south pole at depths as little as 30km, and one involving a 60km to 70km thick convecting ice shell resting above a global ocean.

“Previous predictions were too simple, in that they ignored important details of the structure of Enceladus,” said Francis Nimmo, a planetary scientist at the University of California, Santa Cruz and co-author of the new study. “Enceladus experiences tides from Saturn, which provide a force on the ice shell. The ice shell flows in response to these forces, and because the flow is quite slow, the response is delayed by several hours.”

The research centers around the viscosity of fluids on the moon – its thickness, or the degree to which it resists flow. For instance, water is a relatively low-viscosity fluid while honey is a relatively high-viscosity one. Nimmo’s team found that, while a strong, high-viscosity ice shell would instantly react to tidal forces, a weaker, low-viscosity one would react more gradually, which could be explained by either of their two models.

“The timing of geyser activity gives us an insight into the interior of a rather complicated planetary body,” lead author Marie Běhounková, a planetary scientist at Charles University in Prague, told Space.com. However, more data from the Cassini spacecraft is required before the researchers could try to determine which is the more likely of those models.


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« Reply #34 on: Jul 09, 2015, 06:01 AM »

Is Mars humid enough to support life?

July 8, 2015
Chuck Bednar for redOrbit.com

It might look as dry and arid as a desert, but scientists claim that Mars has a surprisingly high amount of moisture in its atmosphere, leading some experts to ponder whether or not the Red Planet could actually be humid enough to support life.

According to Space.com, the atmospheric moisture on Mars would be especially conducive to life if the water condenses during the early morning hours, forming short-lived puddles on the planet’s surface. This could theoretically make it possible for the planet’s apparently extremely harsh conditions to support living organisms, even without liquid surface water.

East Carolina University biology professor John Rummel, an astrobiology expert who previously worked with NASA, told the website via email that “the conditions on Mars, where the relative humidity is high and the available water vapor is approximately 100 precipitable microns, is the equivalent of the drier parts of the Atacama Desert in Chile.”

Rummel added there were several “special regions,” or zones where terrestrial organisms are likely to replicate on the Red Planet during a discussion at the Astrobiology Science Conference in Chicago last month. Those regions are “interpreted to have high potential for the existence of extant Martian life forms,” according to report.

Lichen-like life

Life here on Earth requires liquid surface water, but even though there is evidence that Mars was once home to liquid H2O, it currently has very little. The air is a different story, as Rummel said that nighttime relative humidity levels can reach as high as 80 to 100 percent.

Earth is home to some types of organisms, including lichens that can survive in arid regions by taking water directly from humid air. In fact, the website explains that some lichens are capable of photosynthesizing when relative humidity levels are as low as 70 percent. Studies indicate that one type of Antarctic lichen can adapt to life under simulated Martian conditions.

However, scientists have yet to discover a terrestrial lifeform that can reproduce under conditions where there is no liquid water, only humidity. Rummel said this doesn’t necessarily prohibit an organism from surviving on Mars. He told Space.com that falling nighttime temperatures may cause water to condense into ice or snow, which would then melt as temperature warm up in the early morning hours. This process could take a few minutes or several hours.

“Such short-term wet periods might be long enough and warm enough to allow for Earth organisms to metabolize and even reproduce,” he said. However, dry conditions aren’t the only thing prohibiting life from living on Mars, the website said – the lack of a global magnetic field, thin atmosphere and radiation levels could force lichen-like organisms underground.


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« Reply #35 on: Jul 09, 2015, 08:50 AM »

‘Puts Star Wars makers to shame': First-of-its-kind five-star solar system discovered

International Business Times
09 Jul 2015 at 09:12 ET 

If there are planets in the vicinity of the 1SWASP J093010.78+533859.5 star system, they would probably be perennially bathed in light from five suns. Located just 250 light-years from Earth, this quintuple star system is the first of its kind to be detected by scientists.

In the cosmic scale, binary star systems -- two stars orbiting each other around a common center of gravity -- are a dime a dozen. Star systems with five stars, however, are believed to be extremely rare.

This particular system consists of a “contact eclipsing binary” wherein the two stars are orbiting so close together that they share an outer atmosphere, a detached binary where the component stars are separated by a distance of about 1.8 million miles and a lone star located nearly 1.2 billion miles from the detached binary. The contact binary system has an orbital period of just under six hours while the detached binaries complete an orbit in just over a day.

An artist’s impression of the five star system 1SWASP J093010.78+533859.5. The smaller orbits are not shown to scale relative to the larger orbit, as the binary components would be too close together to distinguish. The inset images are to scale, along with an image of the Sun for comparison. The blue dotted line marks the orbital path of the two pairs of stars. The fifth star, whose position is uncertain, is to the right of the left pair.  Marcus Lohr

“This is a truly exotic star system. In principle there’s no reason it couldn’t have planets in orbit around each of the pairs of stars. Any inhabitants would have a sky that would put the makers of Star Wars to shame -- there could sometimes be no fewer than five Suns of different brightnesses lighting up the landscape,” Marcus Lohr, from the U.K.’s Open University, who has been studying the star system since 2013, said in a statement. “Days would have dramatically varying light levels as the different stars were eclipsed. They would though miss out on night for a large part of their ‘year’, only experiencing darkness (and a night sky) when the stars were on the same side of their world.”

The presence of these stars was confirmed by astronomers studying data gathered by the international SuperWASP (Wide Angle Search for Planets) project, which provides an accurate measurement of the brightness of stars over time, allowing scientists to plot light curves, graphs depicting brightness against time.

“By combining the data from the five stars’ light curve and their spectra, the Open University researchers have been able to confirm that they are all gravitationally bound together in a single system,” the authors of the study published in the journal Astronomy and Astrophysics, said, in the statement.                 


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« Reply #36 on: Jul 09, 2015, 08:56 AM »

Astronomers observe black hole having breakfast in bed

Agence France-Presse
08 Jul 2015 at 20:47 ET                   

Astronomers who trained their telescopes on a strange stellar blip were rewarded with a front-row seat to the spectacle of a black hole waking up to devour breakfast.

The black hole at the centre of a galaxy 42 million light years away, in the constellation of Pisces, may have been dormant for millions of years, a team reported Thursday.

Scientists surveying the skies were lucky in 2012 to catch a flash of its awakening in a galaxy called NGC 660.

“The odds are pretty slim!” Megan Argo of the University of Manchester’s Jodrell Bank Centre for Astrophysics told AFP.

“It is the first time we can watch it (a black hole awakening) happening in real time, so close to our own galaxy.”

Black holes are very dense regions in spacetime with a gravitational force so strong that even light cannot escape.

They normally lurk dormant and undetected at the centre of galaxies, but can occasionally be tracked by their spectacular feeding frenzies — guzzling gas and dust, sometimes entire stars, and spitting out jets of debris.

In 2012, astronomers using a single radio telescope in Puerto Rico to monitor galaxies, noticed NGC 660 become hundreds of times brighter in just a few months — “a very unlikely and very unusual event,” said Argo.

At first, it was not clear whether the burst was due to an exploding star, or the supermassive black hole.

So a team led by Argo trained radio telescopes in Britain, the Netherlands, Russia, China and South Africa on the galaxy, create a type of composite instrument with which to observe more detail.

They found a “very bright” object at the centre of NGC 660.

“Inactive black holes do not emit large mounts of radiation so we can only detect them by their gravitational effect on the orbits of stars around them. But the black hole in NGC 660 is now very obvious,” said a Royal Astronomical Society (RAS) statement.

Argo said the black hole must have been activated when some material, most likely gas and dust, ventured too close to resist the gravitational pull, and fell in.

How long it remains active will depend on how much “food” there is.

“Studies of this nearby event will help in our understanding of how galaxies evolved over the lifetime of the Universe,” added Argo.

The findings were presented Thursday at a meeting of the RAS National Astronomy Meeting in Llandudno, Wales.


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« Reply #37 on: Jul 10, 2015, 05:42 AM »

‘Pac Man’ satellite to gobble up space junk

July 9, 2015
Chuck Bednar for redOrbit.com – @BednarChuck

Researchers from the Swiss Federal Institute of Technology (EPFL) are drawing inspiration from an iconic video game character from the 1980s for an ongoing research project designed to tidy up the increasing amount of space junk floating in orbit around the Earth.

According to NBC News, the EPFL’s CleanSpace One project has been searching for a method to safely monitor, collect, and dispose of dead satellites not be re-entering the planet’s atmosphere in the foreseeable future, as well as other debris in low-Earth orbit.

On Monday, they opted to use what is being referred to as the “Pac-Man” technique: a spacecraft will be outfitted with a large cone-shaped net that will close once it consumes a satellite, similar to the way the old arcade game character gobbled up dots.

The clean-up satellite will be tested by capturing the SwissCube satellite, a small probe that no longer functions. CleanSpace One will be trapping the satellite, and once it is secure, the satellites will combust together in the atmosphere. The satellite could launch as early as 2018, NBC added.

Complex calculations required for a successful maneuver

Engineers from the Center for Space Engineering and Signal Processing 5 Laboratory (LTS 5) and their colleagues have spent three years working on the “Pac-Man” satellite as an effort to not only capture SwissCube, but other pieces of space debris as well, including projectiles travelling at speeds of up to 7 km per second, posing a threat to functional satellites.

It’s a difficult mission, according to EPFL officials. Christophe Paccolat, a doctoral student working at LTS5, said SwissCube “is not only a 10cm by 10cm object that’s tough to grasp, but it also has darker and lighter parts that reflect sunlight differently,” that can “perturb the visual approach system and thus also the estimates of its speed and distance.”

Likewise, project leader Muriel Richard-Noca said the mission is delicate, and that it takes just “one error in the calculation of the approach for SwissCube to bounce off CleanSpace One and rocket out into space.” To prevent that from happening, the researchers have constantly been testing the visual approach algorithms that will be used by the cleanup satellite, accounting for a variety of factors such as the CubeSat’s speed and the Sun’s angle of illumination.

Michel Lauria, an industrial technology professor whose students were involved in the project, said the Pac-Man method of capture was selected because it is “more reliable and offers a larger margin for maneuvering than a claw or an articulated hand.”

Click to watch: https://www.youtube.com/watch?v=pclqbhRKkdM


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« Reply #38 on: Jul 11, 2015, 05:36 AM »

Sun’s activity to reach lowest point since last ‘mini ice age’

July 10, 2015
Chuck Bednar for redOrbit.com

Solar activity is expected to decrease by 60 percent during the 2030s, plummeting conditions to those not seen since Earth underwent its last “mini ice age” starting in 1645, according to new research presented Thursday at the UK National Astronomy Meeting in Llandudno, north Wales.

In their study, Professor Valentina Zharkova from the Northumbria University Department of Mathematics and Information Sciences and her colleagues explained that, by using a new model of the Sun’s solar cycle, they have been able to produce “unprecedentedly accurate predictions of irregularities” within the 11-year “heartbeat” of our solar system’s central star.

Their model uses dynamo effects in two layers of the Sun, one close to the surface and one deep within its convection zone, and predicts the drastic decline in solar activity. Previously, scientists attributed the cause of the solar cycle to caused by convecting fluid deep within the Sun, but that did not explain for differences and fluctuations unique to each cycle. The addition of the second dynamo, closer to the surface, gives them a more complete and accurate picture of events.

“We found magnetic wave components appearing in pairs, originating in two different layers in the Sun’s interior,” Zharkova explained. “They both have a frequency of approximately 11 years, although this frequency is slightly different, and they are offset in time. Over the cycle, the waves fluctuate between the northern and southern hemispheres of the Sun.”

Dynamos to become completely out of synch by 2030

She and her colleagues developed their model using a technique known as “principal component analysis” to analyze magnetic field observations from the California’s Wilcox Solar Observatory. They studies three solar cycles worth of magnetic field activity, and found that by combining the two waves together, they could predict solar cycle activity with a 97 percent success rate.

Furthermore, they compared their predictions to average sunspot numbers, another strong marker of solar activity, and found that the observations and predictions matched closely. Based on their new model, they predict that the two waves will become increasingly offset during a cycle which peaks in 2022, and will become completely out of sync during the cycle afterwards (2030 -2040), which will result in “a significant reduction in solar activity.”

During that cycle, “the two waves exactly mirror each other – peaking at the same time but in opposite hemispheres of the Sun,” Zharkova explained. “Their interaction will be disruptive, or they will nearly cancel each other. We predict that this will lead to the properties of a ‘Maunder minimum’.”

“Effectively, when the waves are approximately in phase, they can show strong interaction, or resonance, and we have strong solar activity,” she added. “When they are out of phase, we have solar minimums. When there is full phase separation, we have the conditions last seen during the Maunder minimum, 370 years ago.”


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« Reply #39 on: Jul 11, 2015, 05:41 AM »

Venus atmosphere studied with rare transit images

July 10, 2015
Brett Smith for redOrbit.com – @ParkstBrett

Venus passes between us on Earth and the Sun just twice every 115 years and researchers have taken advantage of this recently-occurring event, known as a transit, to learn something about the various layers of the planet’s atmosphere.

In a new study, researchers described how they used a recent transit of Venus to analyze the composition of elements found in the planet’s atmosphere.

Since various elements absorb light somewhat differently, scientists measured the absorption of the Sun’s light passing through Venus’ atmosphere to find out what kinds of molecules can be found there. This piece of data is critical for planning missions to Venus, as atmospheric elements and compounds can affect the drag of a spacecraft when it enters the atmosphere.

Investigating the Venus transit

“Learning more about the composition of the atmosphere is very important for understanding the braking process for spacecraft when they enter the upper atmosphere of the planet, a process called aerobraking,” study author Fabio Reale said in a press release.

Throughout the transit, just the sides of the atmosphere were seen. However, they were especially interesting regions. On Venus, these are the areas where day becomes night and night becomes day, and these transition areas can set up interesting effects in the ionosphere. The information from the Venus transit revealed these two transition areas are practically the same.

“The planet appeared very round in all wavelengths,” said study author Dean Pesnell, a project scientist at NASA’s Goddard Space Flight Center. “If the transition from day to night were different from the transition from night to day, you would expect a bulge in the atmosphere on one side of the planet.”

Investigating the Venus transit can also help with research on planets around other stars, as exoplanets are typically uncovered by transits just like the one in this latest study. The more we can view transiting planets close to home, the more it will educate us on how to analyze planets that we can’t currently see very well. When instrument technology progresses, we may be able to collect better data on the atmospheres of exoplanets as well.

“In the future, there might be missions that have enough sensitivity to detect the difference in radius in different wavelengths,” Reale said. “In particular, if there are exoplanets with an extremely thick thermosphere, the size difference in different wavelengths will be larger and there will be a better chance of detecting the change.”


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« Reply #40 on: Jul 11, 2015, 07:13 AM »

Earth-like planets in the Milky Way three times more likely than previously thought

Newsweek
11 Jul 2015 at 08:42 ET

New research has revealed that the elemental building blocks required to make Earth minerals are ubiquitious throughout the Milky Way, making the presence of Earth-like planets three times more likely than was previously believed.

Brad Gibson, a professor at the University of Hull in the U.K., presented the research at the National Astronomy Meeting in Llandudno, Wales on Wednesday, telling the gathered audience that every solar system has the same elemental building blocks as ours.

Prior to Gibson's research, scientists grouped planets into three categories: those richer in carbon, those with more magnesium and silicon, and those similar to Earth. The latest study, conducted with a team from E. A. Milne Centre for Astrophysics at the University of Hull, found that the minerals responsible for the landscapes of the planets in our solar system, and other systems where planets orbit stars, are made up of four elements: silicon, magnesium, carbon and oxygen. The exact ratio of these elements to one another, and the amount of pressure in a planet's atmosphere, determines the land masses and the heating and cooling of the planet's surface. That, in turn, dictates the weather and if the planet is hospitable to organic life.

Our own solar system exemplifies how not all planets with these building blocks have the potential to sustain life. "We only need to look to Mars and Venus to see how differently terrestrial planets can evolve," Gibson concluded. "However, if the building blocks are there, then it's more likely that you will get Earth-like planets – and three times more likely than we'd previously thought."

These discoveries came out of a simulation that Gibson's team designed in order to better understand the chemical evolution of the Milky Way. After they first ran the simulation, they were suprised to find the results did not match up with previous models.

"At first, I thought we'd got the model wrong," Gibson said at the conference. "As an overall representation of the Milky Way, everything was pretty much perfect. Everything was in the right place; the rates of stars forming and stars dying, individual elements and isotopes all matched observations of what the Milky Way is really like." But once they looked closely, they realized that the older findings had missed some key pieces of information. For one thing, previous attempts to figure out the chemical makeup of planetary systems looked only at large planets orbiting very bright stars, which the new study says can lead to uncertainties of 10 to 20 percent. In addition, they say, previous research teams did not have access to the technology needed to accurately identify the spectra of oxygen and nickel.   

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« Reply #41 on: Jul 13, 2015, 06:23 AM »

Life-sustaining planets may be more common that previously thought

Shayne Jacopian for redOrbit.com
7/13/2015

Life-sustaining planets may not be as uncommon as previously thought—a new study has revealed that the basic ingredients for Earth-like planets can be found on rocky planets everywhere, contrary to the findings of a previous study that said these ingredients could only be found on relatively few planets.

Carbon, oxygen, and magnesium can all be found in many rocky planets. It was previously thought that only some contained these elements, but it turns out, the presence of these elements in in the right ratios is required for a planet to have an Earth-like crust.

"The ratio of elements on Earth has led to the chemical conditions 'just right' for life," said Brad Gibson, an astrophysicist at the University of Hull in the United Kingdom and the lead researcher for this study.

"Too much magnesium or too little silicon, and your planet ends up having the wrong balance between minerals to form the type of rocks that make up the Earth's crust," he added. "Too much carbon, and your rocky planet might turn out to be more like the graphite in your pencil than the surface of a planet like the Earth."

These findings come from a simulation of how the Milky Way galaxy was formed.

Here's an interesting video about the study on space.com

Pretty neat, huh?

Of course, just because a planet has the same kind of terrain as Earth doesn’t necessarily mean it will support life. Size and proximity to a star (and the size of that star, for that matter) all come into play.

These new findings certainly increase a given planet’s odds, though. Maybe we're not alone out there.


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« Reply #42 on: Jul 16, 2015, 05:39 AM »

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Astronomers discover 'Jupiter 2.0.' Could Earth 2.0 be next?

A planet and star closely resembling Jupiter and our sun have been spotted, leading scientists to believe there could also be an Earth-like planet out there.

By Gretel Kauffman, Staff writer July 15, 2015   

Jupiter has a doppelgänger, and it could help us find a planet identical to Earth.

A Brazilian-led team of scientists, researching sun-like stars in an attempt to find planetary systems similar to our own solar system, have discovered a planet with a very similar mass to Jupiter. What’s more, it orbits a star that looks like our sun, has the same mass, and is even the same age.

This is not the first Jupiter-sized planet found orbiting a Sun-like star. What sets this discovery apart is how closely it echoes both Jupiter's mass and its distance from its host star, and the similarities between its host star and the Sun.

Most astronomers agree that Jupiter’s strong gravitational influence played a prominent role in the formation of our solar system, and even in allowing life to thrive on Earth. The discovery of "Jupiter 2.0" opens up the possibility that planets very similar to Earth could also exist elsewhere in our galaxy, researchers say.

"The quest for an Earth 2.0, and for a complete Solar System 2.0, is one of the most exciting endeavors in astronomy," said Jorge Melendez, leader of the study and co-author of a paper that will appear in the journal Astronomy and Astrophysics, in a statement. "We are thrilled to be part of this cutting-edge research."

Jupiter 2.0 was found using the HARPS instrument, mounted on the European Southern Observatory’s 3.6-meter telescope at the La Silla Observatory in Chile. The instrument uses the radial velocity method to tease out the slight wobble caused by the gravitational tugging of exoplanets on their parent stars. By deriving the frequency of the wobbles, astronomers are able to calculate a planet’s mass, orbital distance, and period.

"After two decades of hunting for exoplanets, we are finally beginning to see long-period gas giant planets similar to those in our own solar system, thanks to the long-term stability of planet hunting instruments like HARPS," said Megan Bedell, study collaborator and lead author of the paper. "This discovery is, in every respect, an exciting sign that other solar systems may be out there waiting to be discovered."


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« Reply #43 on: Jul 17, 2015, 05:27 AM »

July 16, 2015

Scientists map out the universe’s dark matter

by Brett Smith
Red Orbit

Dark matter is thought to make up 80 percent of all mass in the universe, and yet because it doesn’t absorb or emit light – scientists can only make educated guesses as to its whereabouts.

Despite this difficulty,an international team of researchers has announced the creation of a dark matter map through research described in two recently published studies: one in the journal Physical Review D and one in the journal Physical Review Letters.

The map was created using data from the Dark Energy Survey (DES), an astrophysical survey that maps about one-eighth of the visible sky. While the DES is primarily dedicated to finding dark energy, the theoretical power driving the expansion of the universe, it can also help search for dark matter.

Researchers need an accurate measurement of all the matter in the universe and where it’s situated in order to complete cosmological tests accurately, said study author Vinu Vikraman, a postdoctoral researcher at the federal government's Argonne National Laboratory, in a press release.

Why do we need a dark matter map?

“We don’t know what dark matter really is or how to directly locate it in the universe,” Vikraman said. “This map will act as a valuable tool for cosmology to answer some of these questions, including those related to dark energy.”

The researchers were able to develop a “mass map” using weak gravitational lensing shear measurements created by the DES. Gravitational lensing is the bending of light caused by the mass encompassing all galaxies. This bending produces a distortion, or shear, of the galaxy’s shape, which researchers can then examine to find out the density and matter dispersal of the gravitational lens.

After creating the map, the scientists contrasted it to a new optical galaxy distribution map, also made from DES information. The data allowed the researchers to check for patterns in the dispersal of galaxies and dark matter.

“It also allows us to check our work,” Vikraman said, “since the distribution of galaxies is expected to trace the distribution of dark matter.”

The research team said connection between the galaxy distribution and the mass map is near what was projected by cosmological simulations that factor an accelerating growth of the universe.


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« Reply #44 on: Jul 17, 2015, 06:04 AM »

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To infinity and beyond? What comes after Pluto

New Horizon's mission could extend beyond Pluto to explore the Kuiper Belt region. Eventually, the spacecraft will head on a never-ending trip out of the solar system.

By Sarah Caspari, Staff writer July 16, 2015   

Now that New Horizons’s nine-and-a-half year journey toward Pluto is complete, the work for scientists back on earth has just begun. But what comes next for the NASA spacecraft – a victory lap, or a life of quiet exile?

It all depends on funding, for now. Principal investigator Alan Stern has said he and his team are hoping to secure a grant to extend the mission. But eventually, New Horizons will be sent out to pasture in deep space.

Dr. Stern told Scientific American that New Horizons has the potential to run through the "mid to late 2030s," meaning that getting closer to Pluto than any spacecraft in history may be only one page in a long story of accomplishments.

"We've found two small objects, each roughly 50 kilometers across, for a potential post-Pluto flyby in 2019," Stern said, though the piano-sized spacecraft will only be able to visit one of the two, since they are each about a billion miles away from Pluto, in opposite directions.

"These are ancient, primordial building blocks of the Kuiper Belt planets," he explained, "and we could see them up close!"

The Kuiper Belt, a thick field of comet nuclei and icy bodies orbiting the sun far beyond the planets, includes "a few very exotic, very diverse small planets," said Stern.

"We’re curious about our place in the universe, and here’s a chance to understand the third region of the solar system, the Kuiper Belt objects, because those are probably the origins of planets," NASA spokesman Randii Wessen told McClatchy.

Eventually, New Horizons will follow its predecessors, two Pioneer and two Voyager spacecraft, on a path out of the solar system.

Pioneer 10 and 11 and Voyager 1 and 2 were all launched in the 1970s. Now, the Pioneers are "dead," but still heading out beyond the sun’s gravitational pull, Mr. Wessen said.

NASA gave the Pioneer missions "enough speed that the pull of the sun is going to slow them up," he said, "but it won’t stop them from their departure from the solar system. So they’re just going to glide, dead, leaving our star forever."

Voyager 1 and 2, the two slightly younger NASA missions, still transmit about 16 hours of data to NASA each day. Voyager 1 escaped the solar system in August 2012 and is now traveling through interstellar space. At 12 billion miles away, it is the farthest spacecraft from the sun, and the only one in interstellar space.

Both Voyagers are running out of power, says Wessen. "We’re slowly turning off things to reduce the electrical demand, so the power we do have is used for the critical systems."

When NASA first launched these spacecraft, they had to think ahead, not only anticipating their decades-long scientific missions, but also what – or whom – the vehicles might encounter.

The Voyagers, the Pioneers, and New Horizons all contain information and messages in case the vehicles reach intelligent beings, such as drawings of human figures, the ashes of the scientist who discovered Pluto, an American flag, and recordings of music and sounds that "symbolize mankind."

But that contact, if possible, is still a long way off, noted Wessen. Voyager 1 is some 72,000 years away from the nearest star.

"We're not even out of the driveway. We’re just starting to put our little toe out into the cosmic seas to see what’s out there," he said, adding, "I think it’s more likely that we’ll be able to fish these spacecraft out of the drink and bring them back than that they would be intercepted by some alien system."


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