Month: January 2017

NuSTAR Helps Solve ‘Rapid Burster’ Mystery

Scientists observing a neutron star in the “Rapid Burster” system may have solved a 40-year-old mystery surrounding its puzzling X-ray bursts.

Discovered in the 1970s, the Rapid Burster is a binary system comprising a low-mass star in its prime and a neutron star — the compact remnant of a massive star’s demise. The gravitational pull of the neutron star strips its companion of some of its gas, which then forms an accretion disk and spirals toward the neutron star.

Most neutron star binary systems continuously release large amounts of X-rays, punctuated by additional X-ray flashes every few hours or days. But scientists have wondered for decades about what accounts for the Rapid Burster’s sudden, erratic and extremely intense X-ray emissions — a phenomenon seen only in one other binary system.

In the new study, researchers discovered that the neutron star’s magnetic field creates a gap between the star and the disk around it, largely preventing it from feeding on matter from its stellar companion. Gas builds up until, under certain conditions, it hits the neutron star all at once, producing intense flashes of X-rays.

The new results provide the first evidence for what causes these so-called “type-II” bursts. The discovery was made with the European Space Agency’s XMM-Newton mission and NASA’s NuSTAR (Nuclear Spectroscopic Telescope Array) and Swift missions.

Full ESA story

Elizabeth Landau
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6425
elizabeth.landau@jpl.nasa.gov

Jakob van den Eijnden
Anton Pannekoek Institute for Astronomy, University of Amsterdam, The Netherlands
a.j.vandeneijnden@uva.nl
+31-6-4816-3504

Additional contacts:
Nathalie Degenaar/Anton Pannekoek Institute for Astronomy, University of Amsterdam, The Netherlands–degenaar@uva.nl
+31-20-525-3994

Norbert Schartel/European Space Agency, Villanueva de la Cañada (Madrid)
Norbert.Schartel@esa.int  +34-91-8131-184

Written by C. Mignone/ESA

Photo Credit: NASA

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How Stressful Will a Trip to Mars Be on the Human Body? We Now Have a Peek Into What the NASA Twins Study Will Reveal

Preliminary research results from the NASA Twins Study debuted at NASA’s Human Research Program’s annual Investigators’ Workshop in Galveston, Texas the week of January 23. NASA astronaut Scott Kelly returned home last March after nearly one year in space living on the International Space Station.  His identical twin brother, Mark, remained on Earth.

Researchers found this to be a great opportunity for a nature versus nurture study, thus the Twins Study was formed. Using Mark, a retired NASA astronaut, as a ground-based control subject, ten researchers are sharing biological samples taken from each twin before, during and after Scott’s mission. From these samples, knowledge is gained as to how the body is affected by extended time in space. These studies are far from complete. Additional research analysis is in process.

Mike Snyder, the Integrated Omics investigator, reported altered levels of a panel of lipids in Scott (the flight twin) that indicate inflammation. Additionally, there was an increased presence of 3-indolepropionic (IPA) in Mark (the ground-based twin). This metabolite is known to be produced only by bacteria in the gut and is being investigated as a potential brain antioxidant therapeutic. IPA is also known to help maintain normal insulin activity to regulate blood sugar after meals.

Susan Bailey’s investigation focuses on Telomeres and Telomerase. It is understood that when looked at over many years, telomeres decrease in length as a person ages. Interestingly, on a time scale of just one year, Bailey found Scott’s telomeres on the ends of chromosomes in his white blood cells increased in length while in space. This could be linked to increased exercise and reduced caloric intake during the mission. However, upon his return to Earth, they began to shorten again. Interestingly, telomerase activity (the enzyme that repairs the telomeres and lengthens them) increased in both twins in November, which may be related to a significant, stressful family event happening around that time.

Mathias Basner’s study, Cognitive Performance in Spaceflight, is looking at cognition, especially the difference found during a 12-month mission as compared to six-month missions. Following the one-year mission, he found a slight decrease in speed and accuracy post mission. Overall, however, the data does not support a relevant change in cognitive performance in flight by increasing the mission duration from six to 12 months.

In the Biochemical Profile investigation, headed by Scott Smith, there appeared to be a decline in bone formation during the second half of Scott’s mission. Also, by looking at C Reactive Protein levels (a widely accepted biochemical marker for inflammation), there appeared to be a spike in inflammation soon after landing, likely related to the stresses of reentry and landing. The stress hormone Cortisol was low normal throughout the one-year mission, but IGF-1 hormone levels increased over the course of the year. This hormone is implicated with bone and muscle health and was likely impacted by heavy exercise countermeasures during flight.

Fred Turek’s focus is on the Microbiome in the GI Tract – or “bugs” naturally found in the gut to aid in digestion. Differences in the viral, bacterial, and fungal microbiome between the twins were pronounced at all time points; however, this was expected due to their differing diet and environment. Of interest were the differences in microbial species observed in Scott on the ground versus his time in space. One shift was a change in the ratio of two dominant bacterial groups (i.e., Firmicutes and Bacteroidetes) present in his GI tract. The ratio of one group to the other increased during flight and returned to pre-flight levels upon return to Earth.

Emmanuel Mignot’s investigation, Immunome Studies, looks at changes in the body before and after a flu vaccine was administered to each twin. Following flu vaccines, “personalized” T cell receptors were created. These unique T cell receptors increased in both twins which were the expected immune response that protects from catching the flu.

Chris Mason is performing Genome Sequencing on the DNA and RNA contained within the twins’ white blood cells with his investigation. Whole genome sequencing was completed and showed each twin has hundreds of unique mutations in their genome, which are normal variants. RNA (transcriptome) sequencing showed more than 200,000 RNA molecules that were expressed differently between the twins. They will look closer to see if a “space gene” could have been activated while Scott was in space.

Andy Feinberg studies Epigenomics, or how the environment regulates our gene expression. In the DNA within Scott’s white blood cells, he found that the level of methylation, or chemical modifications to DNA, decreased while in-flight – including a gene regulating telomeres, but returned to normal upon return. On the ground, Mark’s level of methylation in the DNA derived from his white blood cells increased at the midpoint in the study but returned to normal in the end. Variability was observed in the methylation patterns from both twins; however, this epigenetic noise was slightly higher in Scott during spaceflight and then returned to baseline levels after return to Earth. These results could indicate genes that are more sensitive to a changing environment whether on Earth or in space.

Through further research integrating these preliminary findings, in coordination with other physiological, psychological, and technological investigations, NASA and its partners will continue to ensure that astronauts undertake future space exploration missions safely, efficiently and effectively. A joint summary publication is planned for later in 2017, to be followed by investigator research articles.

###

NASA’s Human Research Program enables space exploration by reducing the risks to human health and performance through a focused program of basic, applied, and operational research. This leads to the development and delivery of: human health, performance, and habitability standards; countermeasures and risk mitigation solutions; and advanced habitability and medical support technologies.

Monica Edwards
Laurie Abadie
NASA Human Research Engagement & Communications

Photo Credit: NASA

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Media and liberals: Changing words to change the narrative

By Robert J. Garrison 

The biggest news story the past few days has been President Trump’s signing of an executive order banning immigration from seven middle eastern countries.

I want to make the record clear this is NOT a Muslim ban, it is an immigration pause! Yet every protester and media outlet is calling it a Muslim ban. It’s a small yet significant change. It is also a popular psychological tactic. This is a psychological tactic is used by an opposing faction to gain control of the narrative. Also, this is only a temporary ban imposed for 90 days.

So many people are talking about an issue that they don’t even have a clue about. They believe the talking points of the MSM like MSNBC, CNN, or the Huffington Post. So many protesters and media outlets haven’t even read the text of the executive order.

For my readers, here is the text of the executive order.

I understand that we are busy with work, texting, posting on social media or running out to protest but let us stop and take the time to actually read the text without viewing it through the filter of news commentators and writers.

I also implore that we all take the time to actually study the topic or issue rather than allow our emotions whip us into a frenzy. For instance, this is not a permanent ban. It is a temporary one, so the new administration can review the vetting process and make tweaks to the vetting process if needed. Also, the government is not stopping everyone from coming in, they are granting waivers to those that were in transit or have already been cleared. Now that we have cut through the hysteria a little, let us look at the premise of the executive order.

So what’s the big deal with these seven countries that President Trump banned immigration for 90-120 days? Well, the commonality between the majority of these countries is that they do not have a stable centralized government.

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Well, the commonality between the majority of these countries is that they do not have a stable centralized government. These countries are known as hotbeds of terrorism and since they do not have a strong centralized government it is hard to nearly impossible to get reliable intelligence on those wishing to come into the US. Let us not forget that ISIS has stated that they will use the refugee crisis to infiltrate the West. Places like France and Germany have felt the impact of ISIS’ plan to infiltrate the refugees and President Trump is taking measures to make sure that the US doesn’t. It is not like he made that decision on a whim.

The State Department reported last summer that ISIS tried to enter the US posing as refugees. Also, ISIS bragged back in 2015 that it has successfully infiltrated 1000s of terrorist among the refugees entering Europe. Since ISIS knows that they couldn’t possibly get to the US from countries like Syria, Iraq, or Libya they need to get into Europe and try to get into the US from there. This is the heart of what the executive order is trying to prevent. Now, why only these seven countries? Why wasn’t an obvious country, Saudi Arabia added to the list?

Now, why only these seven countries? Why wasn’t an obvious country, Saudi Arabia added to the list?

Some suggest that it is because of Trumps business ties with Saudi Arabia as to why it wasn’t on the list. White House Chief of Staff Reince Priebus denied that accusation on Meet the Press by explaining how they came up with those seven countries:

“Just like I said very clearly, the countries that were chosen in the executive order to protect Americans from terrorists were the countries that have already been identified by Congress and the Obama administration,”

White House Press Secretary, Sean Spicer on Monday also suggested that other countries could be added to the list at a later date.

Saudi Arabia should be added to the list, not only because 15 of the 9-11 hijackers were from there but because of their government sponsor of Wahhabism, which is a very extreme form of Islam. Also, Saudi Arabia sponsors 100s of madrasas (Islamic education institutions such as elementary/high schools or colleges) that teach this extreme form of Islam here in the US!

So, are Trump’s business ties the reason why Saudi Arabia wasn’t added to the list? I don’t think so and here’s why. What is more likely the reason why and fits the Trump method is leverage.

The reason that more likely fits the Trump method of doing deals, is leverage. President Trump last weekend made calls to many major world leaders, one of them being the King of Saudi Arabia, King Salman. During this call, King Salman agreed to provide safe zones in Syria and Yemen and to provide help for displaced refugees. President Trump during the election campaign has always called on the Arab world to step up and help the refugees themselves and not leaving only the West to deal with it. So, the leverage theory is more in line with what President Trump has stated before and his political tactics than the business dealing ties.

While the implementation of the executive order was not perfect nor was the list of countries, the reasoning behind the order was. The Trump administration is erring on the side of caution when it comes to the nation’s security and for that, we should be grateful.

While some might be inconvenienced because of this order isn’t that better than being inconvenienced by an attack on US soil?

Photo Credit: Wikiepedia

Robert J. Garrison is a political and religious writer for The Systems Scientist. You can connect with him directly in the comments section, follow him on Twitter or on Facebook, or catch up on his articles in the Archives.

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Copyright ©2016 – The Systems Scientist

Major Review Completed for NASA’s New SLS Exploration Upper Stage

NASA has successfully completed the exploration upper stage (EUS) preliminary design review for the powerful Space Launch System rocket. The detailed assessment is a big step forward in being ready for more capable human and robotic missions to deep space, including the first crewed flight of SLS and NASA’s Orion spacecraft in 2021.

Expanded view of the next configuration of NASA's Space Launch System rocket

An expanded view of the next configuration of NASA’s Space Launch System rocket, including the four RL10 engines.

Credits: NASA

“To send humans and even more cargo farther away from Earth than ever before, NASA decided to add a more powerful upper stage — the upper part of the rocket that continues to operate after launch and ascent,” said Kent Chojnacki, EUS team lead and preliminary design review manager.

“With the completion of this review, our teams will start developing components and materials for the EUS, and build up tooling,” he added. “Full-scale manufacturing will begin after the critical design phase is completed.” Critical design review is the next programmatic milestone that will provide a final look at the design and development of the EUS before beginning full-scale fabrication.

Starting with that first crewed mission, future configurations of SLS will include the larger exploration upper stage and use four RL10C-3 engines. The EUS will replace the interim cryogenic propulsion stage that will be used on the initial configuration of SLS for the first, uncrewed flight with Orion. The EUS will use an 8.4-meter diameter liquid hydrogen tank and a 5.5-meter diameter liquid oxygen tank. A new universal stage adapter will connect the EUS to the Orion spacecraft, and be capable of carrying large co-manifested payloads, such as a habitat.

The preliminary design review kicked off Nov. 30, 2016, with approximately 500 experts from across NASA and industry assessing more than 320 items on the EUS, including documents and data. This review had a new “techie” touch to it with the incorporation of virtual reality glasses, which gave teams enhanced visuals of how the EUS is put together and a broader perspective on the size of the hardware. The preliminary design review board was completed Jan. 19, with the board voting unanimously that the EUS is ready to move to the critical design phase.

“I couldn’t be prouder of the SLS Stages team completing this review,” said SLS Program Manager John Honeycutt. “We continue to make progress on hardware for SLS’s first flight, while also working on the next-generation rocket that will take astronauts to deep-space destinations, like Mars.”

The powerful stage will be built at NASA’s Michoud Assembly Facility in New Orleans. Massive welding machines, like the Vertical Assembly Center, currently building the SLS core stage, also will help build the EUS liquid hydrogen tank. New tooling and assembly areas will be put in place to manufacture the liquid oxygen tank.

Once built, the EUS structural test article will undergo qualification testing at NASA’s Marshall Space Flight Center in Huntsville, Alabama, to ensure the hardware can withstand the incredible stresses of launch. “Green run” testing on the first flight article will be done at NASA’s Stennis Space Center near Bay St. Louis, Mississippi. For the test, the EUS and RL10 engines will fire up together for the first time before being sent to Kennedy Space Center in Florida for the 2021 launch.

As shown in this new animation, future configurations of NASA’s Space Launch System rocket will include a powerful exploration upper stage (EUS) with four RL10C-3 engines. This is the part of the rocket that continues to operate after launch and ascent. The EUS will use an 8.4-meter diameter liquid hydrogen tank and a 5.5-meter diameter liquid oxygen tank. A new universal stage adapter will connect the EUS to the NASA’s Orion spacecraft, and be capable of carrying large co-manifested payloads, such as a habitat, on the same flight as Orion. NASA successfully completed a preliminary design review for the EUS in late January. Now, the SLS team will start developing components and materials for the EUS, and build up tooling. The EUS is first slated to be part of the 105-metric-ton SLS that will be the first flight carrying Orion and astronauts. The detailed assessment is a step forward for the agency’s capabilities for human and robotic missions to deep space including future missions to Mars.

Credits: NASA

Kim Henry
Marshall Space Flight Center
Huntsville, Ala.

kimberly.m.henry@nasa.gov

256-684-6658

Tracy McMahan
Marshall Space Flight Center
Huntsville, Ala.

tracy.mcmahan@nasa.gov

256–682-5326

Photo Credit: NASA

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NASA’s Fermi Discovers the Most Extreme Blazars Yet

NASA’s Fermi Gamma-ray Space Telescope has identified the farthest gamma-ray blazars, a type of galaxy whose intense emissions are powered by supersized black holes. Light from the most distant object began its journey to us when the universe was 1.4 billion years old, or nearly 10 percent of its present age.

NASA’s Fermi Gamma-ray Space Telescope has discovered the five most distant gamma-ray blazars yet known. The light detected by Fermi left these galaxies by the time the universe was two billion years old. Two of these galaxies harbor billion-solar-mass black holes that challenge current ideas about how quickly such monsters could grow.

Credits: NASA’s Goddard Space Flight Center/Scott Wiessinger, producer

“Despite their youth, these far-flung blazars host some of the most massive black holes known,” said Roopesh Ojha, an astronomer at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “That they developed so early in cosmic history challenges current ideas of how supermassive black holes form and grow, and we want to find more of these objects to help us better understand the process.”

Ojha presented the findings Monday, Jan. 30, at the American Physical Society meeting in Washington, and a paper describing the results has been submitted to The Astrophysical Journal Letters.

Blazars constitute roughly half of the gamma-ray sources detected by Fermi’s Large Area Telescope (LAT). Astronomers think their high-energy emissions are powered by matter heated and torn apart as it falls from a storage, or accretion, disk toward a supermassive black hole with a million or more times the sun’s mass. A small part of this infalling material becomes redirected into a pair of particle jets, which blast outward in opposite directions at nearly the speed of light. Blazars appear bright in all forms of light, including gamma rays, the highest-energy light, when one of the jets happens to point almost directly toward us.

Previously, the most distant blazars detected by Fermi emitted their light when the universe was about 2.1 billion years old. Earlier observations showed that the most distant blazars produce most of their light at energies right in between the range detected by the LAT and current X-ray satellites, which made finding them extremely difficult.

Then, in 2015, the Fermi team released a full reprocessing of all LAT data, called Pass 8, that ushered in so many improvements astronomers said it was like having a brand new instrument. The LAT’s boosted sensitivity at lower energies increased the chances of discovering more far-off blazars.

The research team was led by Vaidehi Paliya and Marco Ajello at Clemson University in South Carolina and included Dario Gasparrini at the Italian Space Agency’s Science Data Center in Rome as well as Ojha. They began by searching for the most distant sources in a catalog of 1.4 million quasars, a galaxy class closely related to blazars. Because only the brightest sources can be detected at great cosmic distances, they then eliminated all but the brightest objects at radio wavelengths from the list. With a final sample of about 1,100 objects, the scientists then examined LAT data for all of them, resulting in the detection of five new gamma-ray blazars.

Expressed in terms of redshift, astronomers’ preferred measure of the deep cosmos, the new blazars range from redshift 3.3 to 4.31, which means the light we now detect from them started on its way when the universe was between 1.9 and 1.4 billion years old, respectively.

“Once we found these sources, we collected all the available multiwavelength data on them and derived properties like the black hole mass, the accretion disk luminosity, and the jet power,” said Paliya.

Two of the blazars boast black holes of a billion solar masses or more. All of the objects possess extremely luminous accretion disks that emit more than two trillion times the energy output of our sun. This means matter is continuously falling inward, corralled into a disk and heated before making the final plunge to the black hole.

“The main question now is how these huge black holes could have formed in such a young universe,” said Gasparrini. “We don’t know what mechanisms triggered their rapid development.”

In the meantime, the team plans to continue a deep search for additional examples.

“We think Fermi has detected just the tip of the iceberg, the first examples of a galaxy population that previously has not been detected in gamma rays,” said Ajello.

NASA’s Fermi Gamma-ray Space Telescope is an astrophysics and particle physics partnership, developed in collaboration with the U.S. Department of Energy and with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden and the United States.

For more information on Fermi, visit:

https://www.nasa.gov/fermi

Related


By Francis Reddy

NASA’s Goddard Space Flight Center, Greenbelt, Md.

Photo Credit: NASA 

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NASA’s Fermi Sees Gamma Rays from ‘Hidden’ Solar Flares

An international science team says NASA’s Fermi Gamma-ray Space Telescope has observed high-energy light from solar eruptions located on the far side of the sun, which should block direct light from these events. This apparent paradox is providing solar scientists with a unique tool for exploring how charged particles are accelerated to nearly the speed of light and move across the sun during solar flares.

“Fermi is seeing gamma rays from the side of the sun we’re facing, but the emission is produced by streams of particles blasted out of solar flares on the far side of the sun,” said Nicola Omodei, a researcher at Stanford University in California. “These particles must travel some 300,000 miles within about five minutes of the eruption to produce this light.”

Omodei presented the findings on Monday, Jan. 30, at the American Physical Society meeting in Washington, and a paper describing the results will be published online in The Astrophysical Journal on Jan. 31.

On three occasions, NASA’s Fermi Gamma-ray Space Telescope has detected gamma rays from solar storms on the far side of the sun, emission the Earth-orbiting satellite shouldn’t be able to detect. Particles accelerated by these eruptions somehow reach around to produce a gamma-ray glow on the side of the sun facing Earth and Fermi. Watch to learn more.

Credits: NASA’s Goddard Space Flight Center/Scott Wiessinger, producer

Fermi has doubled the number of these rare events, called behind-the-limb flares, since it began scanning the sky in 2008. Its Large Area Telescope (LAT) has captured gamma rays with energies reaching 3 billion electron volts, some 30 times greater than the most energetic light previously associated with these “hidden” flares.

Thanks to NASA’s Solar Terrestrial Relations Observatory (STEREO) spacecraft, which were monitoring the solar far side when the eruptions occurred, the Fermi events mark the first time scientists have direct imaging of beyond-the-limb solar flares associated with high-energy gamma rays.

triptych of satellite solar flare observations

These solar flares were imaged in extreme ultraviolet light by NASA’s STEREO satellites, which at the time were viewing the side of the sun facing away from Earth. All three events launched fast coronal mass ejections (CMEs). Although NASA’s Fermi Gamma-ray Space Telescope couldn’t see the eruptions directly, it detected high-energy gamma rays from all of them. Scientists think particles accelerated by the CMEs rained onto the Earth-facing side of the sun and produced the gamma rays. The central image was returned by the STEREO A spacecraft, all others are from STEREO B.

Credits: NASA/STEREO

“Observations by Fermi’s LAT continue to have a significant impact on the solar physics community in their own right, but the addition of STEREO observations provides extremely valuable information of how they mesh with the big picture of solar activity,” said Melissa Pesce-Rollins, a researcher at the National Institute of Nuclear Physics in Pisa, Italy, and a co-author of the paper.

The hidden flares occurred Oct. 11, 2013, and Jan. 6 and Sept. 1, 2014. All three events were associated with fast coronal mass ejections (CMEs), where billion-ton clouds of solar plasma were launched into space. The CME from the most recent event was moving at nearly 5 million miles an hour as it left the sun. Researchers suspect particles accelerated at the leading edge of the CMEs were responsible for the gamma-ray emission.

Large magnetic field structures can connect the acceleration site with distant part of the solar surface. Because charged particles must remain attached to magnetic field lines, the research team thinks particles accelerated at the CME traveled to the sun’s visible side along magnetic field lines connecting both locations. As the particles impacted the surface, they generated gamma-ray emission through a variety of processes. One prominent mechanism is thought to be proton collisions that result in a particle called a pion, which quickly decays into gamma rays.

In its first eight years, Fermi has detected high-energy emission from more than 40 solar flares. More than half of these are ranked as moderate, or M class, events. In 2012, Fermi caught the highest-energy emission ever detected from the sun during a powerful X-class flare, from which the LAT detected high­energy gamma rays for more than 20 record-setting hours.

NASA’s Fermi Gamma-ray Space Telescope is an astrophysics and particle physics partnership, developed in collaboration with the U.S. Department of Energy and with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden and the United States.

For more information on Fermi, visit:

https://www.nasa.gov/fermi


By Francis Reddy

NASA’s Goddard Space Flight Center, Greenbelt, Md.

Photo Credit: NASA

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New Planet Imager Delivers First Science

A new device on the W.M. Keck Observatory in Hawaii has delivered its first images, showing a ring of planet-forming dust around a star, and separately, a cool, star-like body, called a brown dwarf, lying near its companion star.

The device, called a vortex coronagraph, was recently installed inside NIRC2 (Near Infrared Camera 2), the workhorse infrared imaging camera at Keck. It has the potential to image planetary systems and brown dwarfs closer to their host stars than any other instrument in the world.

“The vortex coronagraph allows us to peer into the regions around stars where giant planets like Jupiter and Saturn supposedly form,” said Dmitri Mawet, research scientist at NASA’s Jet Propulsion Laboratory and Caltech, both in Pasadena. “Before now, we were only able to image gas giants that are born much farther out. With the vortex, we will be able to see planets orbiting as close to their stars as Jupiter is to our sun, or about two to three times closer than what was possible before.”

The new vortex results are presented in two papers, both published in the January 2017 issue of The Astronomical Journal. One study, led by Gene Serabyn of JPL, the overall lead of the Keck vortex project, presents the first direct image of the brown dwarf called HIP79124 B. This brown dwarf is located 23 astronomical units from a star (an astronomical unit is the distance between our sun and Earth) in a nearby star-forming region called Scorpius-Centaurus.

“The ability to see very close to stars also allows us to search for planets around more distant stars, where the planets and stars would appear closer together. Having the ability to survey distant stars for planets is important for catching planets still forming,” said Serabyn. He also led a team that tested a predecessor of the vortex device on the Hale Telescope at Caltech’s Palomar Observatory, near San Diego. In 2010, the team secured high-contrast images of three planets orbiting in the distant reaches of the star system called HR8799.

The second vortex study, led by Mawet, presents an image of the innermost of three rings of dusty, planet-forming material around the young star called HD141569A. The results, when combined with infrared data from NASA’s Spitzer and WISE missions, and the European Space Agency’s Herschel mission, reveal that the star’s planet-forming material is made up of pebble-size grains of olivine, one of the most abundant silicates in Earth’s mantle. The data also show that the temperature of the innermost ring imaged by the vortex is about minus 280 degrees Fahrenheit (100 Kelvin, or minus 173 degrees Celsius), a bit warmer than our asteroid belt.

“The three rings around this young star are nested like Russian dolls and undergoing dramatic changes reminiscent of planetary formation,” said Mawet. “We have shown that silicate grains have agglomerated into pebbles, which are the building blocks of planet embryos.”

About the vortex coronagraph

The vortex was invented in 2005 by Mawet while he was at the University of Liege in Belgium. The Keck vortex coronagraph was built by a combination of the University of Liege, Uppsala University in Sweden, JPL and Caltech.

The first science images and results from the vortex instrument demonstrate its ability to image planet-forming regions hidden under the glare of stars. Stars outshine planets by a factor of few thousand to a few billion, making the dim light of planets very difficult to see, especially for planets that lie close to their stars. To deal with this challenge, researchers have invented Instruments called coronagraphs, which typically use tiny masks to block the starlight, much like blocking the bright sun with your hand or a car visor to see better.

What makes the vortex coronagraph unique is that it does not block the starlight with a mask, but instead redirects light away from the detectors using a technique in which light waves are combined and canceled out. Because the vortex doesn’t require an occulting mask, it has the advantage of taking images of regions closer to stars than other coronagraphs. Mawet likens the process to the eye of a storm.

“The instrument is called a vortex coronagraph because the starlight is centered on an optical singularity, which creates a dark hole at the location of the image of the star,” said Mawet. “Hurricanes have a singularity at their centers where the wind speeds drop to zero — the eye of the storm. Our vortex coronagraph is basically the eye of an optical storm where we send the starlight.”

What’s next for the vortex

In the future, the vortex will look at many more young planetary systems, in particular planets near the “frost lines,” which are the region around a star where temperatures are cold enough for volatile molecules, such as water, methane and carbon dioxide, to condense into solid icy grains. The frost line is thought to divide a solar system into regions where planets are likely to become rocky or gas giants. Surveys of the frost line region by the vortex coronagraph will help answer ongoing puzzles about a class of hot, giant planets found extremely close to their stars — the “hot Jupiters,” and “hot Neptunes.” Did these planets first form close to the frost line and migrate in, or did they form right next to their stars? “With a bit of luck, we might catch planets in the process of migrating through the planet-forming disk, by looking at these very young objects,” Mawet said.

“The power of the vortex lies in its ability to image planets very close to their star, something that we can’t do for Earth-like planets yet,” said Serabyn. “The vortex coronagraph may be key to taking the first images of a pale blue dot like our own.”

The Keck Observatory is managed by Caltech and the University of California. In 1996, NASA joined as a one-sixth partner in the Keck Observatory. JPL is managed by Caltech for NASA.

Elizabeth Landau
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6425

elizabeth.landau@jpl.nasa.gov

Whitney Clavin
Caltech, Pasadena, Calif.
626-395-1856

wclavin@caltech.edu

Written by Whitney Clavin

Photo Credit: NASA

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