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Space News Update — October 13, 2015 —

Contents

In the News

Story 1: Delving deeper into KSC’s transformation into a Multi-User Spaceport

Story 2: Young Stars' Flickering Light Reveals Link with Matter-Eating Black Holes

Story 3: Comet Encke: A Solar Windsock Observed by NASA’s STEREO

Departments

The Night Sky

ISS Sighting Opportunities

Space Calendar

NASA-TV Highlights

Food for Thought

Space Image of the Week

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1. Delving deeper into KSC’s transformation into a Multi-User Spaceport

The 2011 conclusion of NASA’s 30-year Space Shuttle Program posed a major challenge for the Kennedy Space Center, the historic spaceport dotted with facilities purpose-built for shuttles. Eleven months before the shuttle program ended, NASA developed post-shuttle plans for its facilities and operations. Five years later, KSC is into the final leg of its transformation. A New Vision for a Historic Spaceport:

The changing face of KSC has a primary focus of ensuring it remains the key destination for flagship launches into space. Those changes range from its multi-faceted role, through to physical alterations to its facilities.

Some of its iconic buildings, such as former shuttle launch pad 39B and sections of the center’s cavernousVehicle Assembly Building (VAB), were repurposed to support NASA’s Space Launch System rocket andOrion crew vehicle, which are slated for human missions in the 2020s.

Other facilities and assets, however, such as NASA’s hangar-like orbiter processing facilities (OPFs) and the three-mile Shuttle Landing Facility (SLF), were not required for NASA’s future missions.

Once the shuttles were retired to museums around America, KSC’s unused facilities and assets gradually

became available to external partners including companies, other government entities and academic institutions.

KSC also decided to offer its external partners spacecraft processing services and testing capabilities, such as manufacturing assistance, launch control systems sharing, vibro-acoustics testing, and cryogenic engineering.

KSC established the Center Planning and Development Directorate (CPD), a new team within its command chain, to negotiate potential partnerships. The team handles public inquiries about using KSC property, assets and services. In addition, CDP oversees long-term master planning in order to effectively manage KSC’s growth.

Scott Colloredo, director of Center Planning and Development at NASA’s Kennedy Space Center (KSC), spoke with NASASpaceFlight about KSC’s transformation from a single-program center to a multi-user spaceport – noting how innovative partnerships allow the center to become stronger and more flexible.

“The center director made a bold initiative to go in this direction. And, frankly, it would have been easier to go in a different direction and not take the aggressive approach to allow companies to use the assets that weren’t going to be used post-shuttle,” Mr. Colloredo noted.

“We had the opportunity to transform ourselves from a single-program center, for the most part, to what we now call a multi-user spaceport. That was the fork in the road where we decided we had to do things differently.”

Space for Partners:

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The process of selection for facility users is one that is classed as “competitive and careful”, according to Mr. Colloredo.

“We ensure that our high-value, critical facilities are treated as competitive partnerships,” he added. “So, we make a formal announcement that’s public, that allows any company or other entity to provide a proposal. And then, based on the merits of the proposal and the criteria that we’ve established, we essentially select the partner.”

The first iconic shuttle facility to receive a new identity was OPF-3, which KSC leased to Space Florida, the state of Florida’s aerospace economic development agency.

Space Florida subleased the facility to aerospace giant Boeing, which renamed it the Commercial Crew and Cargo Processing Facility (C3PF). There, Boeing will process their new CST-100 Starliner Spacecraft, which will ferry NASA astronauts to the International Space Station (ISS).

Further successful leases followed.

NASA designated 39B as the launch pad for the agency’s future human missions to deep space, but it had no further plans for 39A.

Launch pad 39A regained its purpose in 2014 when SpaceX leased it in order to launch the company’s upcoming Falcon Heavy rocket, as well as human missions to the ISS aboard the SpaceX Crew Dragon spacecraft.

With 39A and other facilities, partners have freedom to modify preexisting structures.

“The partners are able to virtually do anything they need to do to get their rockets off the ground,” Mr. Colloredo added. “We don’t require them to keep

things in a prior configuration.”

In June 2015, the shuttle’s former runway also took on a new role, when NASA handed the SLF’s operation and management to Space Florida through a 30-year lease.

For years the SLF has been scouted as a prime location for horizontal space launches, including suborbital space tourism.

The VAB also had space for new partners.

While some areas of the facility are reserved for SLS assembly, others were vacant following the conclusion of shuttle operations.

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NASA announced that High Bay 2, one of the VAB’s four 456-foot-high assembly areas, was available to partners. Included with High Bay 2 were all three of KSC’s mobile launcher platforms (MLPs), the pedestals that Saturn rockets and space shuttles stood upon for launches.

The Spaceport of Tomorrow:

With most of the major former shuttle facilities either repurposed by current partners or available to future partners, KSC is developing into a bustling spaceport. The drive to expand KSC’s multi-user capabilities creates even more partnership opportunities.

In July, NASA completed construction of KSC’s newest launch pad, 39C, located just within the perimeter of pad 39B. NASA hopes to attract commercial providers of small-class rockets to the pad – with Firefly Space Systems one of the many interested future tenants.

Launch pad 39C potentially will foster further growth of the small satellite launch industry as well as increase opportunities for universities and other institutions to fly their own spacecraft.

39C is envisioned to support a diverse range of users, Mr. Colloredo noted.

“We saw a need in industry of not just one or two companies, but a few companies. We built this very inexpensive launch site. We’re up to probably 19 or 20 companies that have an interest in using the asset.

“As far as the companies go, they’re varied. They’re all in the same general class of vehicle, but use different commodities. Some use liquid oxygen (LOX) and rocket-propellant 1 (a form of kerosene), some are LOX and methane, some use solid fuel, so they’re very different.

“They’re different in maturity, but they all have a strong interest in launching ultimately from Florida.

“Even though it’s a very lean, clean pad, it provides what they need. 39C provides a basic infrastructure, controlled airspace and the range. So, it provides what

they need to get their job done.”

Since much of KSC shares nitrogen and helium sources, NASA will ensure that 39B and 39C activities are coordinated to avoid any resource use conflicts, Mr. Colloredo added. In addition, NASA never will allow the pads to host vehicles simultaneously.

“We do need to be very cognizant of the timing and the scheduling of various activities. Part of our job is to

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make sure that a wet dress rehearsal on one vehicle doesn’t time out on the same day as a launch on another. They usually would take enough of the commodity that you wouldn’t be able to support both at the same time.”

The end result envisions launches from 39A, 39B, 39C and the SLF to drastically increase the launch rate from KSC. In addition, increased launches from Cape Canaveral Air Force Station (CCAFS), KSC’s neighbor on Cape Canaveral, will further fill the area’s skies. Last month, for instance, the company Blue Origin announced plans to launch new rockets and human spacecraft from CCAFS.

“In 20 years, I would expect to see around a dozen launch sites active with probably two or three dozen users launching on a regular basis, more than likely multiple times a day,” Mr. Colloredo noted. “I would be shocked if we’re not launching three to four times a day in the not-too-distant future.”

The increased launch rate will challenge the Eastern Range, an area of sky and ocean maintained by the Air Force that allows rockets to fly within a safe zone that does not endanger people.

The range parameters are not constant across launches and depend on the type of rocket being

launched. The time needed to establish the range parameters and clear the area of people could be strained by a greatly increased launch rate and a much wider variety of vehicles. However, the Air Force is working to meet the challenge.

“We’re now known – between KSC and the Cape Canaveral Air Force Station – as the busiest spaceport in the world,” added Mr. Colloredo. “The launch rate over the next two years is higher than we’ve ever seen. So, that does provide unique challenges.

“The range has always accommodated any rocket that needed to get off the ground. But, going forward, the launch rate – particularly with a diverse number of launchers that aren’t launching the same thing over and over – the range will have to morph, and the Air Force is being very progressive.

“They see the changes coming. Some of them are their rockets, some of them are our rockets and some of

them are commercial. They recognize that and they’re working toward that. I think a lot of people probably forget the range has been able to do a high number of launches.

“I think they’ve done as many as four or so a day for certain missions when they were identical rockets. It’s only when they change that it’s a tougher challenge, and that’s what we’re bringing to the table.”

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According to Mr. Colloredo, KSC’s growth is part of a global rise in access to space.

KSC and commercial spaceports cropping up around the world can be mutually beneficial, he noted. The SLF, for instance, can benefit from a network of similar facilities for use in point-to-point space flight, a concept in which suborbital space flights are used to send people around the globe much more rapidly than with conventional air travel.

“I’m a firm believer that a rising tide raises all boats. Whenever states, countries, companies, any organization decides to get into space, we view that as a good thing. We think we’re the world leader in a lot

of areas – capacity, volume, just basic capabilities across the board – but we welcome the world to join us in that.

“We do think we have a huge advantage being close to the equator on the east coast of the United States with a free market economy. We don’t rest on our laurels, but we certainly take advantage of the assets we have.”

With KSC partnerships growing and multiple iconic center facilities given new life, Mr. Colloredo said that CPD has been hugely successful, but the team’s work for KSC is far from over.

“I would say Center Planning and Development’s greatest accomplishment would be transforming the art of the possible for a NASA center, particularly at Kennedy. I don’t think in our wildest dreams we would have envisioned Kennedy on the cusp of what we’re doing now just four years ago.

“I think the biggest accomplishment is just creating an environment for the successes we’re seeing. We’re not taking that for granted. We’re making sure every day that future partnerships can take advantage of that as well.

“Even though we’ve engaged quite a few partnerships to get where we are, we’re not done yet. We’re still talking to companies that want to come to Florida, particularly in the small-class area.

“Basically any aerospace company you’ve heard of, we’ve probably talked to them and more than likely are in some sort of discussion of potentially signing them up through agreements to become another partner to Kennedy.”

Source: NASASpaceflight.com Return to Contents

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2. Young Stars' Flickering Light Reveals Link with Matter-Eating Black Holes

Astronomers have discovered a previously unknown link between the way young stars grow and the way black holes and other exotic space objects feed from their surroundings.

The study, 'Accretion-induced variability links young stellar objects, white dwarfs, and black holes,' which is published in the journal Science Advances, shows how the 'flickering' in the visible brightness of young stellar objects (YSOs) -- very young stars in the final stages of formation -- is similar to the flickering seen from black holes or white dwarfs as they violently pull matter from their surroundings in a process known as accretion.

The researchers found that relatively cool accretion discs around young stars, whose inner edges can be several times the size of the Sun, show the same behavior as the hot, violent accretion discs around planet-size white dwarfs, city-size black holes and supermassive black

holes as large as the entire solar system, supporting the universality of accretion physics.

The study found a relationship between the size of the central object and the speed of the flickering produced by the disc, suggesting the physics of the accretion must be very similar around these different astronomical objects despite them being completely different in other ways, such as size, age, temperature and gravity.

Dr. Simon Vaughan, Reader in Observational Astronomy at the University of Leicester's Department of Physics and Astronomy, explained: "The seemingly random fluctuations we see from the black holes and white dwarfs look remarkably similar to those from the young stellar objects -- it is only the tempo that changes."

The new observations were obtained with Kepler/K2 and ULTRACAM, examining accreting white dwarfs and young stellar objects.

Accretion discs are responsible for the growth and evolution of most celestial objects, from young protostars still in the star forming process to ancient supermassive black holes at the center of galaxies.

NASA's Kepler/K2 telescope can 'listen' to the seemingly random brightness variations produced by accretion discs, revealing how they all sound the same once scaled by their physical size.

Accretion therefore is a universal process operating in the same way across all astrophysical objects. The study was led by Simone Scaringi, a Humboldt Research Fellow at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany.

Source: SpaceRef.com Return to Contents

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3. Comet Encke: A Solar Windsock Observed by NASA’s STEREO

Much like the flapping of a windsock displays the quick changes in wind’s speed and direction, called turbulence, comet tails can be used as probes of the solar wind – the constant flowing stream of material that leaves the sun in all directions. According to new studies of a comet tail observed by NASA’s Solar and Terrestrial Relations Observatory, or STEREO, the vacuum of interplanetary space is filled with turbulence and swirling vortices similar to gusts of wind on Earth. Such turbulence can help explain two of the wind's most curious features: its variable nature and unexpectedly high temperatures. A paper on this work was published in “The Astrophysical Journal” on Oct. 13, 2015.

“The solar wind at Earth is about 70 times hotter than one might expect from the temperature of the solar corona and how much it expands as it crosses the void,” said Craig DeForest, a solar physicist at the Southwest Research Institute in Boulder, Colorado, and lead author on the study. “The source of this extra heat has been a mystery of solar wind physics for several decades.”

There is much that is conclusively known about the solar wind: It is made of a sea of electrically-charged electrons and ions and also carries the interplanetary magnetic field along for the ride, forging a magnetic connection between the sun and Earth and the other planets in the solar system. There is no consensus, however, on what powers the wind's acceleration, especially when it is traveling at its fastest speeds. Complicating the search for such understanding are two of its most distinctive characteristics: The solar wind

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can be highly variable, meaning that measurements just short times or distances apart can yield quite different results. It is also very, very hot—remarkably so.

The new study helped explain these characteristics using the heliospheric imager onboard STEREO. The scientists studied the movements of hundreds of dense chunks of glowing ionized gas within the ribbon of Comet Encke’s tail, which passed within STEREO’s field of view in 2007. Fluctuations in the solar wind are mirrored in what is seen in the tail, so by tracking these clumps, scientists were able to reconstruct the motion of the solar wind, catching an unprecedented look at the turbulence.

Identifying this turbulence in the solar wind has the potential to solve the mystery of how the solar wind gets so hot. Based on the intensity of the turbulence researchers saw, they calculated that the energy available from turbulence is more than ten times what would be required to heat the solar wind to observed temperatures.

What's more, it also helps to solve the variability problem, which other theories have not yet done successfully.

“This turbulent motion mixes up the solar wind, leading to the rapid variation that we see at Earth,” said DeForest.

For years, scientists have taken direct measurements of the solar wind—known as in situ measurements, which are captured as the solar wind passes over one of the dozens of satellites carrying the appropriate instruments. Most of these satellites observe the sun from a vantage point similar to that of Earth. STEREO-A, however, orbits the sun in a slightly smaller and faster orbit than Earth, meaning it moves around the sun farther and farther from Earth over time. So, in addition to the images of Comet Encke as it streamed past in April 2007, STEREO-A also provides us with in situ solar wind measurements from a unique perspective.

On the other hand, the solar wind is notoriously hard to study remotely—that is, with measurements from afar. Its particles flow at 250 miles per second, and they are so dispersed that interplanetary space at Earth’s orbit has about a thousand times fewer particles in one cubic inch of space than the best laboratory vacuum on Earth.

This solar wind dominates the space environment within our solar system and travels well past Pluto, creating a huge bubble known as the heliosphere. Closer to home, the solar wind also interacts with Earth’s magnetic field, sometimes initiating changes in near-Earth space that can disrupt our space technology or cause auroras. So scientists needed to come up with a way to look at something that’s invisible—and that’s where Comet Encke came in.

All comets, if they get close enough to the sun, will form what’s called an ion tail. One of the most recognizable features of these hunks of ice and rock, the ion tail is created when the solar wind—made of hot, charged gas, called plasma—sweeps over the comet, capturing the material that has been vaporized into plasma by sunlight, causing it to trail out behind the comet. This tail follows the lines of the magnetic field embedded in the solar wind and reveals its motion.

Comet Encke has some unusual characteristics that scientists were able to leverage to study the solar wind. Unlike most comets, Comet Encke has what is called a compact tail. Rather than feathering out loosely, creating a wide spray of ions, Comet Encke’s ion tail streams out in a tight, bright ribbon of glowing gas with compact features.

"In situ measurements are limited because they don't follow the turbulence along its path,” said William Matthaeus, a professor of physics and astronomy at the University of Delaware and co-author on the study. “Now, for the first time, we observed the turbulent motions along their complex paths and quantified the mixing. We actually see the turbulence.”

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Using the images from STEREO-A, scientists tracked 230 different features as they weaved through Comet Encke’s tail over the course of about 9.3 million miles of its journey around the sun. They then compared these motions to how they would expect solid objects to orbit around the sun, finding evidence that these gas clumps were being picked up by drag against the solar wind. They found that, though the gas clumps moved more or less randomly on smaller scales, they exhibited clear patterns on the scale of about 300,000 miles, indicating large-scale swirling eddies are mixing the solar wind—and possibly heating it as well.

“Turbulent motion cascades down into motion on smaller and smaller scales until it hits the level of the fundamental gyrations of the particles about the magnetic field, where it becomes heat,” said Aaron Roberts, a heliophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This study estimates that there is enough energy contained in these swirling eddies to explain the extra heat several times over.”

These observations of the solar wind provide a preview of what NASA plans to observe more directly with the Solar Probe Plus, or SPP, mission in 2018. SPP will travel to within nine solar radii of the sun, which is nine times the radius of the Sun, or about 3.9 million miles. Since it’s possible to remotely observe comets closer to the sun than any spacecraft can travel, studying them does provide unique information about the solar wind and our sun’s atmosphere.

Source: NASA Return to Contents

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The Night Sky Tuesday, October 13

The Great Square of Pegasus balances on its corner high in the east at nightfall. Seen from your location, when is it exactly balanced? That is, when is the Square's bottom corner exactly below its top corner? It'll be sometime soon after the end of twilight, depending on both your latitude and longitude.

Wednesday, October 14

Vega is the brightest star very high in the west at nightfall. Arcturus, equally bright, is getting low in the west-northwest. The brightest star in the vast expanse between them, about a third of the way from Arcturus back up toward Vega, is Alphecca, magnitude 2.2 — the crown jewel of Corona Borealis. Alphecca is a 17-day eclipsing binary, but its brightness dips are too slight for the eye to see reliably.

Back in the evening sky, the waxing crescent steps over Saturn (near Beta Scorpii) and Antares. Binoculars help.

Thursday, October 15

Look for the crescent Moon, Saturn, and Antares lined up in the southwest in late twilight, as shown here.

Friday, October 16

The Moon hangs over Saturn and Antares in the southwest at dusk, as shown here.

This is the time of year when, after nightfall, W-shaped Cassiopeia stands on end halfway up the northeastern sky — and when, off to its left, the dim Little Dipper extends leftward from Polaris in the north.

Source: Sky & Telescope Return to Contents

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ISS Sighting Opportunities

For Denver:

Date Visible Max Height Appears Disappears

Tue Oct 13, 7:09 PM 1 min 10° 10° above NNW 10° above N

Wed Oct 14, 7:53 PM 1 min 11° 10° above N 11° above N

Thu Oct 15, 7:01 PM 1 min 10° 10° above N 10° above N

Thu Oct 15, 8:37 PM < 1 min 11° 11° above NNW 11° above NNW

Fri Oct 16, 7:45 PM 2 min 15° 11° above NNW 15° above NNE

Sighting information for other cities can be found at NASA’s Satellite Sighting Information

NASA-TV Highlights (all times Eastern Daylight Time)

1 p.m., Wednesday, October 14 - Venture Class Launch Services Contract Award Announcement (all channels)

9 a.m., Thursday, October 15 - In-Flight Interview with WTOP Radio and KUSA-TV (all channels)

Watch NASA TV on the Net by going to the NASA website. Return to Contents

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Space Calendar • Oct 13 - Cassini, Distant Flyby of Titan • Oct 13 - Comet 212P/NEAT Closest Approach To Earth (2.469 AU) • Oct 13 - Comet C/2014 N3 (NEOWISE) Closest Approach To Earth (3.475 AU) • Oct 13 - [Oct 13] Apollo Asteroid 2015 TC25 Near-Earth Flyby (0.0007 AU) • Oct 13 - Asteroid 9770 Discovery Closest Approach To Earth (1.620 AU) • Oct 13 - Asteroid 65675 Mohr-Gruber Closest Approach To Earth (2.551 AU) • Oct 13 - Lecture: Pluto, Up Close and Personal, Tuscon, Arizona

• Oct 14 - [Oct 13] Cassini, Enceladus Flyby • Oct 14 - Cassini, Distant Flyby of Polydeuces, Methone, Prometheus & Helene • Oct 14 - Comet 220P/McNaught Closest Approach To Earth (1.023 AU) • Oct 14 - Centaur Object 10199 Chariklo Occults 2UCAC 17114281 (14.9 Magnitude Star) • Oct 14 - Asteroid 19155 Lifeson Closest Approach To Earth (1.083 AU) • Oct 14 - Asteroid 49272 Bryce Canyon Closest Approach To Earth (1.223 AU) • Oct 14 - Asteroid 4221 Picasso Closest Approach To Earth (1.924 AU) • Oct 14 - Asteroid 1000 Piazzia Closest Approach To Earth (2.812 AU) • Oct 14 - Dwight Eisenhower's 125th Birthday (1890) • Oct 14-15 - Aero Space Days - Europe, Paris, France • Oct 15 - [Oct 07] Comet P/2015 R1 (PANSTARRS) Closest Approach To Earth (1.435 AU) • Oct 15 - Comet P/2006 F4 At Opposition (3.656 AU) • Oct 15 - Asteroid 93 Minerva Occults 4UC 574-043798 (13.2 Magnitude Star) • Oct 15 - Asteroid 9621 Michaelpalin Closest Approach To Earth (1.099 AU) • Oct 15 - Asteroid 9880 Stegosaurus Closest Approach To Earth (1.131 AU) • Oct 15 - Asteroid 114703 North Dakota Closest Approach To Earth (2.037 AU) • Oct 15 - Gareth Williams' 50th Birthday (1965) • Oct 16 - [Oct 11] TurkSat 4B Proton M-Briz M Launch • Oct 16 - Mercury At Its Greatest Western Elongation (18 Degrees) • Oct 16 - Comet 118P/Shoemaker-Levy Closest Approach To Earth (1.724 AU) • Oct 16 - [Oct 06] Apollo Asteroid 2015 TE Near-Earth Flyby (0.059 AU) • Oct 16 - Asteroid 3000 Leonardo Closest Approach To Earth (0.933 AU) • Oct 16 - Asteroid 61342 Lovejoy Closest Approach To Earth (1.134 AU) • Oct 16 - Asteroid 4017 Disneya Closest Approach To Earth (1.382 AU) • Oct 16 - Asteroid 8129 Michaelbusch Closest Approach To Earth (1.463 AU) • Oct 16 - Asteroid 4134 Schutz Closest Approach To Earth (1.529 AU) • Oct 16 - Asteroid 12432 Usuda Closest Approach To Earth (1.965 AU) • Oct 16 - Kuiper Belt Object 202421 (2005 UQ513) At Opposition (47.390 AU)

Source: JPL Space Calendar Return to Contents

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Food for Thought

New 'Habitability Index' Could Help Guide Search for Alien Life

Researchers have a new way to rank the life-hosting potential of alien worlds.

The "habitability index" metric could help guide the operations of future observatories, such as NASA's James Webb Space Telescope (JWST), that will scan exoplanet atmospheres for signs of life, scientists said.

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"Basically, we've devised a way to take all the observational data that are available and develop a prioritization scheme so that as we move into a time when there are hundreds of targets available, we might be able to say, 'OK, that's the one we want to start with," study lead author Rory Barnes, of the University of Washington, said in a statement.

Traditionally, assessing habitability has been a yes-or-no affair, with researchers attempting to determine whether or not an alien world resides in the "habitable zone" of its host star. This region of space, also known as the "Goldilocks zone," is that just-right range of distances that can allow the existence of liquid water on a planet's surface.

But the new index is more involved, integrating information about an exoplanet's composition (e.g., rocky or not rocky), reflectivity and orbital path to come up with the probability that it can indeed support liquid surface water.

The original concept "was a great first step, but it doesn't make any distinctions within the habitable zone," Barnes said. "Now it's as if Goldilocks has hundreds of bowls of porridge to choose from."

Calculations performed in the new study, which has been accepted for publication in theAstrophysical Journal, suggest that the best candidates for alien life are exoplanets that receive about 60 to 90 percent as much energy from their host stars as Earth gets from the sun, researchers said.

Astronomers have discovered nearly 2,000 exoplanets to date, and many more await confirmation by follow-up observations and analysis. More than half of these finds have come courtesy of NASA's Kepler space telescope, which notices the tiny brightness dips caused when planets cross the face of, or transit, their host stars from the instrument's perspective.

JWST, which is scheduled to launch in late 2018, will also make use of such transits. Among many other tasks, the $8.8 billion observatory will study starlight that passes through exoplanet atmospheres for signs of oxygen, methane and other gases that could have been produced by living organisms.

The new habitability index should help scientists optimize JWST's life-hunting work, study team members said.

"This innovative step allows us to move beyond the two-dimensional habitable zone concept to generate a flexible framework for prioritization that can include multiple observable characteristics and factors that affect planetary habitability," co-author Victoria Meadows, also of the University of Washington, said in the same statement. "The power of the habitability index will grow as we learn more about exoplanets from both observations and theory."

Source: Space.com Return to Contents

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Space Image of the Week

Hubble Sees an Aging Star Wave Goodbye This planetary nebula is called PK 329-02.2 and is located in the constellation of Norma in the southern sky. It is also sometimes referred to as Menzel 2, or Mz 2, named after the astronomer Donald Menzel who discovered the nebula in 1922.

When stars that are around the mass of the sun reach their final stages of life, they shed their outer layers into space, which appear as glowing clouds of gas called planetary nebulae. The ejection of mass in stellar burnout is irregular and not symmetrical, so that planetary nebulae can have very complex shapes. In the case of Menzel 2 the nebula forms a winding blue cloud that perfectly aligns with two stars at its center. In 1999 astronomers discovered that the star at the upper right is in fact the central star of the nebula, and the star to the lower left is probably a true physical companion of the central star.

For tens of thousands of years the stellar core will be cocooned in spectacular clouds of gas and then, over a period of a few thousand years, the gas will fade away into the depths of the universe. The curving structure of Menzel 2 resembles a last goodbye before the star reaches its final stage of retirement as a white dwarf.

Image credit: ESA/ Hubble & NASA, Acknow ledgement: Serge Meunier Text credit: European Space Agency

Source: NASA Return to Contents