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A New Way to Detect Daisy Worlds
The Daisy World model describes a hypothetical planet that self-regulates, maintaining a delicate balance involving its biogeochemical cycles, climate, and feedback loops that keep it habitable. It’s associated with the Gaia Hypothesis developed by James Lovelock. How can we detect these worlds if they’re out there?
By looking closely at information.
A Daisy World (DW) is inhabited by two types of daisies: white and black. They have different albedos, and the blacks absorb more sunlight and warm the planet, while the whites reflect more sunlight and cool the planet.
As the DW’s star brightens, the planet’s temperature rises. At first, black daisies thrive because they absorb more energy. However, as the planet gets hotter, absorbing more energy becomes undesirable, and the white daisies begin to outcompete the blacks and thrive. As they thrive, they reflect more sunlight and cool the planet.
The result is a delicate homeostasis where the daisies regulate the planet’s temperature and keep it in a habitable range. It can’t get too hot and it can’t get too cold. The DW model shows how life can influence a planet’s climate and create conditions favourable for its own survival.
Earth is not exactly a daisy world, but life on Earth influences the climate. The DW model simply illustrates the concept of basic climate feedback mechanisms.
The ESA’s Sentinel 2 satellite captured this image of an algae bloom in the Baltic Sea in 2015. A ship can be seen moving through it. Algae blooms interact with the climate through feedback loops. Image Credit: Copernicus Sentinel data / ESA.In new research, scientists from the Department of Physics and Astronomy and the Department of Computer Science at Rochester University wanted to find ways to analyze how planetary systems like biospheres and geospheres are coupled. If there are self-regulating “Daisy Worlds” out there, how can we detect them?
The research is “Exo-Daisy World: Revisiting Gaia Theory through an Informational Architecture Perspective.” The lead author is Damian Sowinski, a research physicist and postdoctoral associate in the Department of Physics and Astronomy at the University of Rochester. The research is awaiting publishing and is not peer-reviewed yet.
The idea is to find a way to detect agnostic biosignatures on exoplanets. Regular biosignatures are specific chemicals like oxygen or methane that can be byproducts of living organisms. Agnostic biosignatures are indications that life is present but don’t rely on identifying which types of organisms might be producing them. Instead, they’re like overarching planetary patterns that living worlds produce.
For the authors, finding agnostic biosignatures begins with information and how it flows.
“In this study, we extend the classic Daisy World model through the lens of Semantic Information Theory (SIT), aiming to characterize the information flow between the biosphere and planetary environment—what we term the information architecture of Daisy World systems,” the authors explain.
Semantic Information Theory has been around since the mid-20th century. It attempts to define meaning in different contexts, how human subjective interpretation affects it, and related concepts in the same vein. It’s taken on a new focus as artificial intelligence and machine learning become more prevalent.
There’s a drive to understand exoplanet atmospheres and environments and to have a way to differentiate between those that may be life-supporting and those that aren’t. This is a complex problem that hinges on agnostic biosignatures.
The JWST captured this atmospheric spectrum of exoplanet K2-18 b showing the presence of methane, which can act as a biosignature. The authors say that information theory can help undercover agnostic biosignatures. Rather than specific chemicals like methane, agnostic biosignatures are patterns that can only be created by a biosphere. Image Credit: NASA, CSA, ESA, R. Crawford (STScI), J. Olmsted (STScI), Science: N. Madhusudhan (Cambridge University)Agnostic biosignatures are complex patterns and structures that can’t be explained by non-biological processes. There’s also disequilibrium, novel energy transfer, unusual levels of organization at different scales, and cyclical or systematic changes that suggest a biological cause.
A search for agnostic biosignatures can involve complex molecules that need biological synthesis, chemical distributions that require metabolism, unexpected accumulations of specific molecules, and features in an atmosphere or on a planetary surface that require biological maintenance.
Some examples of agnostic biosignatures on Earth are methane and oxygen co-existing in the atmosphere, the ‘Red Edge‘ in Earth’s vegetation spectrum, and daily or seasonal cycles of gas emissions.
The Red Edge is a region of rapid change in vegetation reflectance in the near-infrared (NIR). It could be useful in detecting vegetation on exoplanets. Image Credit: Seager et al. 2024.“The search for life on exoplanets requires the identification of biosignatures, which rely on life having
significantly altered the spectroscopic properties of a planet. Thus, exoplanetary life searches focus not
on detecting individual organisms but on identifying the collective effects of life on the planetary system—what we refer to as exo-biospheres,” the authors explain.
In short, we can’t study biosignatures without studying biospheres. In doing so it’s critical to understand where and how an exo-biosphere reaches a “mature” state where they exert a strong influence on the atmosphere, hydrosphere, cryosphere, and lithosphere, collectively known as the geosphere. Once they’re mature and exert a strong influence, they’re in line with the Daisy World hypothesis.
The authors aim is to study how information flows between a biosphere and the planetary environment. To do this, they modelled potential conditions on M-dwarf exoplanets and came up with equations that describe the co-evolution of the daisies on these worlds with their planetary environments. They created what they term an ‘information narrative’ for exo-Daisy Worlds (eDWs).
Typically, the homeostatic feedback in DWs rests on physical quantities like radiation fluxes, albedos, and plant life coverage fractions. That’s the physical narrative. However, the researchers used Semantic Information Theory to derive a complementary narrative based on how information flows. In their work, SIT focuses on correlations between an agent—the biosphere—and an environment and how those correlations benefit the agent.
Their model showed that as stellar luminosity rises, the correlations between the biosphere and its environment intensify. The correlations correspond to distinct phases of information exchange between the two. This leads to the idea of rein control, a control exerted by flora through the positive and negative differences of their albedos compared to the bare ground. This is how the biosphere exerts a regulatory influence on a planet’s climate. In their informational narrative, the planetary temperatures are more constrained “at the cooler and warmer boundaries of the bearable temperature range.”
Not all of the information that flows between the biosphere and the environment is relevant. The biosphere doesn’t use all of it because some of it doesn’t help the biosphere maintain control. The authors say that by analyzing all this information according to information theory, they can determine which information, and when and how, it contributes to its own viability.
The Daisy World model is instructive, but it’s a toy model. For example, it doesn’t include stochastic events like volcanic eruptions. But the big question is how does it relate to exobiospheres?
The authors say that their work shows the potential in using approaches like SIT to understand how exoplanets and their biospheres co-evolved like they have on Earth. More realistic models will be necessary that include more of the complex networks of interactions between an exoplanet’s living and non-living systems. The biosphere processes information in ways that non-living systems don’t, so information-centric systems can undercover agnostic biosignatures in ways that physical or chemical models can’t.
“As a result, the next step in our research program will involve applying SIT and other information-theoretic approaches to more complex models of coupled planetary systems,” the authors conclude.
The post A New Way to Detect Daisy Worlds appeared first on Universe Today.
NASA Awards Contract for NOAA’s Space Weather Program
NASA, on behalf of the National Oceanic and Atmospheric Administration (NOAA), has selected Southwest Research Institute of San Antonio to build three coronagraphs for the Lagrange 1 Series project, part of NOAA’s Space Weather Next program.
Once operational, the coronagraphs will provide critical data to NOAA’s Space Weather Prediction Center, which issues forecasts, warnings, and alerts that help mitigate space weather impacts, including electric power outages and interruption to communications and navigation systems.
This cost-plus-fixed-fee contract is valued at approximately $60 million, and the anticipated period of performance is from this November through January 2034, concluding after launch of the second coronagraph aboard a NOAA spacecraft. The third coronagraph will be delivered as a flight spare.
This contract award marks a transfer of coronagraph development from the government to the U.S. commercial sector. The contract scope includes design, analysis, development, fabrication, integration, test, verification, and evaluation of the coronagraphs; launch support; supply and maintenance of ground support equipment; and support of post-launch instrument operations at the NOAA Satellite Operations Facility. The work will take place at Southwest Research Institute’s facility in San Antonio.
The coronagraphs will observe the density structure of the Sun’s faint outermost atmosphere — the corona — and will detect Earth-directed coronal mass ejections shortly after they erupt, providing the longest possible lead time for geomagnetic storm watches. With this forewarning, public and private organizations affected by space weather can take actions to protect their assets. The coronagraphs will also provide data continuity from the Space Weather follow-on Lagrange 1 mission.
NASA and NOAA oversee the development, launch, testing and operation of all the satellites in the project. NOAA is the program owner providing the requirements and funding along with managing the program, operations, data products, and dissemination to users. NASA and its commercial partners develop and build the instruments, spacecraft, and provide launch services on behalf of NOAA.
For information about NASA and agency programs, visit:
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Abbey Donaldson
Headquarters, Washington
202-358-1600
Abbey.a.donaldson@nasa.gov
Jeremy Eggers
Goddard Space Flight Center, Greenbelt, Md.
757-824-2958
jeremy.l.eggers@nasa.gov
FAA creating new committee to update launch regulations
NASA Johnson Invites Proposals to Lease Vibration Test Facility
Nov. 14, 2024
NASA Johnson Invites Proposals to Lease Vibration Test Facility
NASA’s Johnson Space Center is seeking proposals for the use of its historic, but underused, Vibration and Acoustic Test Facility. Prospective tenants must submit facility walk-through requests by Monday, Nov. 18.
Final proposals are due by 12 p.m. EST Monday, Dec. 16, and must promote activities that will build, expand, modernize, or operate aerospace-related capabilities at NASA Johnson and help preserve the historic and iconic building through preservation and adaptive reuse.
NASA plans to sign a National Historic Preservation Act (NHPA) lease agreement for the facility, also known as Building 49, for a five-year base period and one five-year extension to be negotiated between NASA and the tenant. To request a walk-through, send an email to hq-realestate@mail.nasa.gov.
“This historic facility has been used for decades to ensure the success and safety of all human spaceflight missions by putting engineering designs and hardware to the ultimate stress tests,” said NASA Johnson Director Vanessa Wyche. “For more than 60 years, NASA Johnson has been the hub of human space exploration and this agreement will be a vital part of the center’s efforts to develop a robust and durable space economy that refines our understanding of the solar system and space exploration.”
All proposals must adhere to the guidelines detailed in the Agency Announcement for Proposals describing concept plans for development of the property, including any modifications proposed to the building; a statement of financial capability to successfully achieve and sustain operations, demonstrated experience with aerospace-related services or other space-related activities, and a detailed approach to propelling the space economy.
The nine-story building complex has a gross square footage of 62,737 square feet and consists of a north wing measuring 62 feet long, 268 feet wide and 106 feet tall, and a central wing about 64 feet long and 115 feet wide. Building 49 currently houses five laboratories, including the General Vibration Laboratory, Modal Operations Laboratory, Sonic Fatigue Laboratory, Spacecraft Acoustic Laboratory, and Spacecraft Vibration Laboratory. The south administrative portion of the building is not included in the property offered for lease.
As the home of Mission Control Center for the agency’s human space missions, astronaut training, robotics, human health and space medicine, NASA Johnson leads the way for the human exploration. Leveraging its unique role and location, the center is developing multiple lease agreements, including the recently announced Exploration Park, to sustain its key role in helping the human spaceflight community foster a robust space.
In the coming years, NASA and its academic, commercial, and international partners will see the completion of the International Space Station Program, the commercial development of low Earth orbit, and the first human Artemis campaign missions establishing sustainable human presence on the Moon in preparation for human missions to Mars.
Johnson already is leading the commercialization of space with the commercial cargo and crew programs and private astronaut missions to the space station. The center also is supporting the development of commercial space stations in low Earth orbit, and lunar-capable commercial spacesuits and lunar landers that will be provided as services to both NASA and the private sector to accelerate human access to space. Through the development of Exploration Park, the center will broaden the scope of the human spaceflight community that is tackling the many difficult challenges ahead.
Learn more about NASA Johnson’s efforts to collaborate with industry partners:
https://www.nasa.gov/johnson/frontdoor
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Kelly Humphries
Johnson Space Center, Houston
281-483-5111
kelly.o.humphries@nasa.gov
NASA, Peru Agree to Study Potential Sounding Rocket Campaign
Lee esta nota de prensa en español aquí.
NASA and Peru’s National Commission for Aerospace Research and Development (CONIDA) laid the groundwork for a potential multi-year scientific rocket launch campaign in the South American country.
Both countries signed a non-binding memorandum of understanding Thursday that includes safety training, a joint feasibility study for the potential campaign, and technical assistance for CONIDA on sounding rocket launches. Sounding rockets are small, low-cost rockets that provide suborbital access to space.
“We are excited to look at the possibility of once again launching sounding rockets from Peru,” said NASA Administrator Bill Nelson, who signed on behalf of the United States. “This agreement deepens our international partnership with Peru and the scientific research we conduct because of the country’s location along the magnetic equator. Together we will go farther.”
Maj. Gen. Roberto Melgar Sheen, head of CONIDA, signed on behalf of Peru. Brian Nichols, assistant secretary for Western Hemisphere Affairs for the U.S. State Department, and Stephanie Syptak-Ramnath, U.S. ambassador to Peru, also participated, among other Peruvian officials. The event took place during the week of the Asia-Pacific Economic Cooperation forum beginning Nov. 9 in Lima.
During his visit to Peru, Nelson also discussed the importance of international partnerships and collaboration in space and celebrated Peru’s signing of the Artemis Accords earlier this year.
The United States and Peru have a long history of space cooperation. NASA conducted sounding rocket campaigns at CONIDA’s Punta Lobos launch base in 1975 and 1983.
NASA uses sounding rockets to carry scientific instruments into space on suborbital flights to collect important science data and test prototype instruments. They yield invaluable data that enhance our understanding of Earth’s atmosphere and weather, our solar system, and the universe, and test equipment for deeper space travel.
Understanding our Earth’s atmosphere and how it is influenced by the Sun is crucial to protecting ground and space-based assets that we rely on every day, from the power grid to weather data and even navigation.
For more information about NASA’s international partnerships, visit:
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Meira Bernstein / Elizabeth Shaw
Headquarters, Washington
202-358-1600
meira.b.bernstein@nasa.gov / elizabeth.a.shaw@nasa.gov
South Pole Safety: Designing the NASA Lunar Rescue System
In the unforgiving lunar environment, the possibility of an astronaut crewmember becoming incapacitated due to unforeseen circumstances (injury, medical emergency, or a mission-related accident) is a critical concern, starting with the upcoming Artemis III mission, where two astronaut crewmembers will explore the Lunar South Pole. The Moon’s surface is littered with rocks ranging from 0.15 to 20 meters in diameter and craters spanning 1 to 30 meters wide, making navigation challenging even under optimal conditions. The low gravity, unique lighting conditions, extreme temperatures, and availability of only one person to perform the rescue, further complicate any rescue efforts. Among the critical concerns is the safety of astronauts during Extravehicular Activities (EVAs). If an astronaut crewmember becomes incapacitated during a mission, the ability to return them safely and promptly to the human landing system is essential. A single crew member should be able to transport an incapacitated crew member distances up to 2 km and a slope of up to 20 degrees on the lunar terrain without the assistance of a lunar rover. This pressing issue opens the door for innovative solutions. We are looking for a cutting-edge design that is low in mass and easy to deploy, enabling one astronaut crewmember to safely transport their suited (343 kg (~755lb)) and fully incapacitated partner back to the human landing system. The solution must perform effectively in the Moon’s extreme South Pole environment and operate independently of a lunar rover. Your creativity and expertise could bridge this critical gap, enhancing the safety measures for future lunar explorers. By addressing this challenge, you have the opportunity to contribute to the next “giant leap” in human space exploration.
Award: $45,000 in total prizes
Open Date: November 14, 2024
Close Date: January 23, 2025
For more information, visit: https://www.herox.com/NASASouthPoleSafety
Asteroid pieces brought to Earth help reveal how our solar system's planets and moons grew
NASA Leadership Hosts Future-Focused Dialogues with Kennedy Employees
NASA Deputy Administrator Pam Melroy (front center left) discusses NASA 2040 on Wednesday, Nov. 13, 2024, the agency’s strategic initiative for aligning workforce, infrastructure, and technologies to meet the needs of the future with various groups of employees at the agency’s Kennedy Space Center in Florida.
The initiative launched in June 2023 to implement meaningful changes to ensure the agency remains the global leader in aerospace and science in the year 2040 while also making the greatest impacts for the nation and the world.
NASA will focus on addressing the agency’s aging infrastructure, shaping an agency workforce strategy, improving decision velocity at many levels, and exploring ways to achieve greater budget flexibility.
Photo credit: NASA/Glenn Benson
Precision Pointing Goes the Distance on NASA Experiment
4 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater) The laser that transmits between NASA’s Psyche spacecraft and Earth-based observatories for the Deep Space Optical Communications experiment successfully reaches its target thanks, in part, to a vibration isolation platform developed by Controlled Dynamics Inc., and supported by several Space Technology Mission Directorate programs. NASA/JPL-Caltech
One year ago today, the future of space communications arrived at Earth as a beam of light from a NASA spacecraft nearly 10 million miles away. That’s 40 times farther than our Moon. That’s like using a laser pointer to track a moving dime from a mile away. That’s pretty precise.
That laser — transmitted from NASA’s DSOC (Deep Space Optical Communications) technology demonstration — has continued to hit its target on Earth from record-breaking distances.
“NASA’s Deep Space Optical Communications features many novel technologies that are needed to precisely point and track the uplink beacon and direct the downlink laser,” said Bill Klipstein, DSOC project manager at NASA’s Jet Propulsion Laboratory in Southern California.
One of the technologies aiding that extremely precise pointing was invented by a small business and fostered by NASA for more than a decade.
Whole Lotta Shakin’ Going On (Not!)Part of the challenge with the precision pointing needed for DSOC was isolating the laser from the spacecraft’s vibrations, which would nudge the beam off target. Fortunately for NASA, Controlled Dynamics Inc. (CDI), in Huntington Beach, California, offered a solution to this problem.
The company had a platform designed to isolate orbiting experiments from vibrations caused by their host spacecraft, other payloads, crew movements, or even their own equipment. Just as the shocks on a car provide a smoother ride, the struts and actuators on CDI’s vibration isolation platform created a stable setting for delicate equipment.
This idea needed to be developed and tested first to prove successful.
The Path to Deep Space SuccessNASA’s Space Technology Mission Directorate started supporting the platform’s development in 2012 under its Game Changing Development program with follow-on support from the SBIR (Small Business Innovation Research) program. The technology really began to take off — pun intended — under NASA’s Flight Opportunities program. Managed out of NASA’s Armstrong Flight Research Center in Edwards, California, Flight Opportunities rapidly demonstrates promising technologies aboard suborbital rockets and other vehicles flown by commercial companies.
Early flight tests in 2013 sufficiently demonstrated the platform’s performance, earning CDI’s technology a spot on the International Space Station in 2016. But the flight testing didn’t end there. A rapid series of flights with Blue Origin, UP Aerospace, and Virgin Galactic put the platform through its paces, including numerous boosts and thruster firings, pyrotechnic shocks, and the forces of reentry and landing.
“Flight Opportunities was instrumental in our development,” said Dr. Scott Green, CDI’s co-founder and the platform’s principal investigator. “With five separate flight campaigns in just eight months, those tests allowed us to build up flight maturity and readiness so we could transition to deep space.”
The vibration isolation platform developed by Controlled Dynamics Inc., and used on the Deep Space Optical Communications experiment conducted numerous tests through NASA’s Flight Opportunities program, including this flight aboard Virgin Galactic’s VSS Unity in February 2019. Virgin Galactic
The culmination of NASA’s investments in CDI’s vibration isolation platform was through its Technology Demonstration Missions program, which along with NASA’s SCaN (Space Communications and Navigation) program supported NASA’s Deep Space Optical Communications.
On Oct. 13, 2023, DSOC launched aboard the Psyche spacecraft, a mission managed by JPL. The CDI isolation platform provided DSOC with the active stabilization and precision pointing needed to successfully transmit a high-definition video of Taters the cat and other sample data from record-breaking distances in deep space.
“Active stabilization of the flight laser transceiver is required to help the project succeed in its goal to downlink high bandwidth data from millions of miles,” said Klipstein. “To do this, we need to measure our pointing and avoid bumping into the spacecraft while we are floating. The CDI struts gave us that capability.”
The Deep Space Optical Communications technology demonstration’s flight laser transceiver is shown at NASA’s Jet Propulsion Laboratory in Southern California in April 2021. The transceiver is mounted on an assembly of struts and actuators — developed by Controlled Dynamics Inc. — that stabilizes the optics from spacecraft vibrations. Several Space Technology Mission Directorate programs supported the vibration isolation technology’s development. NASA/JPL-Caltech Onward Toward Psyche
The Psyche spacecraft is expected to reach its namesake metal-rich asteroid located between Mars and Jupiter by August 2029. In the meantime, the DSOC project team is celebrating recognition as one of TIME’s Inventions of 2024 and expects the experiment to continue adding to its long list of goals met and exceeded in its first year.
By Nancy Pekar
NASA’s Flight Opportunities Program
Space Technology Mission Directorate
Deep Space Optical Communications (DSOC)
Game Changing Development
Flight Opportunities
Share Details Last Updated Nov 14, 2024 EditorLoura Hall Related Terms55 Years Ago: Apollo 12 Launches
55 Years Ago: Apollo 12 Launches
The Apollo 12 spacecraft launches from NASA’s Kennedy Space Center in Florida in this image from Nov. 14, 1969, with astronauts Charles Conrad Jr., Richard F. Gordon Jr., and Alan L. Bean aboard. During liftoff, the Saturn V rocket which carried the Apollo capsule was struck twice by lightning.
On Nov. 19, 1969, the lunar module landed on the Moon. About three hours after landing, Conrad emerged from the lunar module, becoming the third person to step on the Moon. He was followed by Bean.
Image credit: NASA
China launching Tianzhou 8 cargo mission to Tiangong space station on Nov. 15
Plumes of pollution from big factories can make it snow
Plumes of pollution from big factories can make it snow
What Bird Flu in Wastewater Means for California and Beyond
Wastewater in several Californian cities, including San Francisco and Los Angeles, recently tested positive for bird flu. But understanding disease risk and exposure to humans isn’t so straightforward
Two Supermassive Black Holes on the Verge of a Merger
In March 2021, astronomers observed a high-energy burst of light from a distant galaxy. Assigned the name AT 2021hdr, it was thought to be a supernova. However, there were enough interesting features that flagged as potentially interesting by the Automatic Learning for the Rapid Classification of Events (ALeRCE). In 2022, another outburst was observed, and over time the Zwicky Transient Facility (ZTF) found a pattern of outbursts every 60–90 days. It clearly wasn’t a supernova, but it was unclear on what it could be until a recent study solved the mystery.
One idea was that AT 2021hdr was a tidal disruption event (TDE),] where a star strays too close to a black hole and is ripped apart. This can create periodic bursts as the stellar remnant orbits the black hole, but TDEs don’t tend to have such regular patterns. So the team considered another model, where a massive interstellar cloud passes into the realm of a pair of binary black holes.
Simulations show how binary black holes interact with a gas cloud. Credit: F. Goicovic et al. 2016Computer simulations show that rather than simply ripping apart the cloud, a binary black hole would churn the cloud as it consumes it. This would produce a periodic burst of light as the black holes orbit. The team observed AT 2021hdr using the Neil Gehrels Swift Observatory and found periodic oscillations of ultraviolet and X-ray light that match the transient bursts observed by ZTF. These observations match the simulations of a binary black hole.
Based on the data, the black holes have a combined mass of about 40 million Suns, and they orbit each other every 130 days. If they continue along their paths, the two black holes will merge in about 70,000 years. Without the passing cloud, we would have never noticed them.
The team plans to continue their observations of the system to further refine their model. They also plan to study how the black holes interact with their home galaxy.
Reference: L. Hernández-García, et al. “AT 2021hdr: A candidate tidal disruption of a gas cloud by a binary super massive black hole system.” Astronomy & Astrophysics 691 (2024)
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Brilliant fireball explodes over North America as satellites capture flash from space (video)
Is this the best Black Friday camera deal ever? The Canon EOS R5 is nearly $1500 off the MSRP
Interferometry Will Be the Key to Resolving Exoplanets
When it comes to telescopes, bigger really is better. A larger telescope brings with it the ability to see fainter objects and also to be able to see more detail. Typically we have relied upon larger and larger single aperture telescopes in our attempts to distinguish exoplanets around other stars. Space telescopes have also been employed but all that may be about to change. A new paper suggests that multiple telescopes working together as interferometers are what’s needed.
When telescopes were invented they were single aperture instruments. A new technique emerged in the late 1800’s to combine optics from multiple instruments. This achieved higher resolution than would ordinarily be achieved by the instruments operating on their own. The concept involves analysis of the interference pattern when the incoming light from all the individual optical elements is combined. This is used very successfully in radio astronomy for example at the aptly named Very Large Array. It is not just radio waves that are used, infra-red and even visible light interferometers have been developed saving significant costs and producing results that would otherwise not be achievable from a single instrument.
Image of radio telescopes at the Karl G. Jansky Very Large Array, located in Socorro, New Mexico. (Credit: National Radio Astronomy Observatory)One area of astronomical research is the study of exoplanets. Observing alien worlds orbiting distant stars presents a number of challenges but the two key difficulties are that they lie at great distances and orbit bright stars. The planets are usually small and faint making them almost (but not quite) impossible to study directly due to the brightness and proximity to their star. Some understanding of their nature can be gleaned from using the transit method of study. This involves studying starlight as it passes through any atmosphere present to reveal its composition.
Direct imaging and study is a little more challenging and requires high resolution and sometimes a way of blocking light from the nearby star. To achieve direct observations requires angular resolution of a few milliarcseconds or even less (the full Moon covers 1,860,000 milliarcseconds!) This depends largely on the planets size and distance from Earth and from its host star. To give some idea of context, to resolve a planet like Earth orbiting the Sun from a distance of just 10 light years requires an angular resolution of 0.1 milliarcseconds. The James Webb Space Telescope has a resolution of 70 milliarcseconds so even that will struggle.
This artist’s impression depicts the exomoon candidate Kepler-1625b-i, the planet it is orbiting and the star in the centre of the star system. Kepler-1625b-i is the first exomoon candidate and, if confirmed, the first moon to be found outside the Solar System. Like many exoplanets, Kepler-1625b-i was discovered using the transit method. Exomoons are difficult to find because they are smaller than their companion planets, so their transit signal is weak, and their position in the system changes with each transit because of their orbit. This requires extensive modelling and data analysis.A paper recently authored by Amit Kumar Jha from the University of Arizona and a team of astronomers explores this very possibility. They look at using interferometry techniques to achieve the required resolutions, at using advanced imaging techniques like the Quantum Binary Spatial Mode Demultiplexing to analyse the point spread function (familiar to amateur astronomical imagers) and at using quantum based detectors.
The study draws upon radio interferometric techniques with promising results. They showed that a multi-aperture interferometry approach utilising quantum based detectors are more effective than single aperture instruments. They will provide a super-resolution imaging solution that has to date not been used in exoplanetary research. Not only will it hugely increase resolution, it’s also a very cost effective way to observe exoplanets and indeed other objects across the cosmos.
The post Interferometry Will Be the Key to Resolving Exoplanets appeared first on Universe Today.