Feed aggregator
JWST Uses “Interferometry Mode” to Reveal Two Protoplanets Around a Young Star
The JWST is flexing its muscles with its interferometry mode. Researchers used it to study a well-known extrasolar system called PDS 70. The goal? To test the interferometry mode and see how it performs when observing a complex target.
The mode uses the telescope’s NIRISS (Near Infrared Imager and Slitless Spectrograph) as an interferometer. It’s called Aperture Masking Interferometry (AMI) and it allows the JWST to reach its highest level of spatial resolution.
A team of astronomers used the JWST’s AMI to observe the PDS 70 system. PDS 70 is a young T-Tauri star about 5.4 million years old. At that young age, its protoplanetary disk still surrounds it. PDS 70 is a well-studied system that’s caught the attention of astronomers. It’s unique because its two planets, PDS 70 b and c, make it the only multiplanet protoplanetary disk system we know of.
The researchers wanted to determine how easily the AMI would find PDS 70’s two known planets and what else it could observe in the system.
Their research is “The James Webb Interferometer: Space-based interferometric detections of PDS 70 b and c at 4.8 µm.” It’s available on the pre-print site arxiv.org and hasn’t been peer-reviewed yet. The lead author is Dori Blakely from the Department of Physics and Astronomy at the University of Victoria, BC, Canada.
PDS 70 is known for its pair of planets. PDS 70 b is about 3.2 Jupiter masses and follows a 123-year orbital period. PDS 70 c is about 7.5 Jupiter masses and follows a 191-year orbit. One of the most puzzling things about the system is that PDS 70 b appears to have its own accretion disk. The system also shows intriguing evidence of a third body, maybe another star.
The JWST’s interferometry easily detected both planets. In fact, the observations found evidence of circumplanetary disk emissions around PDS 70 b and c. “Our photometry of both PDS 70 b and c provide evidence for circumplanetary disk emission,” the researchers write. That means we can see the star and its protoplanetary disk, where planets form, and the individual circumplanetary disks around each planet. Those disks are where moons form, and seeing them in a system 366 light-years away is very impressive.
The PDS 70 system as seen by the JWST’s interferometry mode and after extensive data processing. A yellow star marks the location of PDS 70, with PDS 70 b and c also shown. The JWST shows the infrared emissions coming from the disk. Image Credit: Blakely et al. 2024.The JWST’s AMI observations also found a third point source. Its light is different from the light from the pair of planets and more similar to the light from the star. If it’s another planet, its composition is different from the others. If it’s not another planet, that doesn’t mean it necessarily has to be another star. The JWST could be seeing scattered starlight from another gaseous, dusty structure or clump in the disk. “This indicates that what we observe is not due to a simple inner disk structure, and may hint at a complex inner disk morphology such as a spiral or clumpy features,” the researchers explain.
The unexplained third source could be something more exotic. Previous research also identified the source and suggested that it could be an accretion stream flowing between PDS 70 b and c. “We interpret its signal in the direct vicinity of planet c as tracing the accretion stream feeding its circumplanetary disk,” the authors of the previous research wrote.
These images are from previous research that used the JWST but not its interferometry mode. The top row is from the telescope’s F187N filter, and the bottom row is from the telescope’s F480M filter. The left column shows the complete images. The middle column shows the system with the disk subtracted. The right column shows the system with the disk and both known planets extracted. What remains is a potential third planet, planet “d,” and an arm-like feature and potential accretion stream. Image Credit: V. Christiaens et al. 2024.Or, perhaps most exciting, the source could be another planet. “Another scenario is that the signal we observe is due to an additional planet interior to the orbit of PDS 70 b,” the authors explain. “Follow-up observations will be needed to determine the nature of this emission,” the authors write.
Part of the observations’ success comes from what it didn’t detect. Protoplanetary disks are dusty and difficult to examine. The JWST has a leg up on it because it can see infrared light. When used in interferometry mode, it’s a powerful tool. The fact that it failed to detect any other planets is progress, though. “Additionally, we place the deepest constraints on additional planets,” in part of the disk. These constraints will help future researchers examine the PDS 70 system and other extrasolar systems.
The results also show another of AMI’s strengths: its ability to see into parts of the parameter space that other telescopes can’t. “Furthermore, our results show that NIRISS/AMI can reliably measure relative astrometry and contrasts of young planets in a part of parameter space (small separations and moderate to high contrasts) that is unique to this observing mode, and inaccessible to all other present facilities at 4.8 µm,” the authors explain.
The JWST has already established its place in the history of astronomy. It’s delivered on its promise and has already significantly contributed to our understanding of the cosmos. The telescope’s observations with its Aperture Masking Interferometry mode will further cement its place in history.
“Here, using the power of the James Webb Interferometer, we detect PDS 70, its outer disk, and its two protoplanets, b and c. These are the first planets detected with space-based interferometry,” the authors write.
The post JWST Uses “Interferometry Mode” to Reveal Two Protoplanets Around a Young Star appeared first on Universe Today.
Major Martian Milestones
There’s good news from NASA’s Cloudspotting on Mars project! That’s the project that invites you to help identify exotic clouds high in the Martian atmosphere.
- Thanks to your help, the Cloudspotting on Mars project reached ahuge milestone. Another full Mars year, Mars Year 30 (Oct 2009 – Sep 2011), has been completed! That’s the second full Mars year of observations that has been analyzed since the project began.
- The team has uploaded another full year of data, Mars Year 31 (Sep 2011 – Aug 2013). You’ll find right here, ready for you to investigate.
- A new project from the Cloudspotting on Mars team has started its beta testing phase! In this new project, you’ll pick out cloud shapes in data from NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) Mission. If you’re willing to help beta test this project and provide feedback before it launches, please send an email to the team. We’ll let everyone know when this project officially launches, of course!
Congratulations to the Cloudspotting on Mars team and all the volunteers who have helped spot Martian clouds!
Facebook logo @DoNASAScience @DoNASAScience Share Details Last Updated Apr 29, 2024 Related Terms Explore More 6 min read Pushing the Limits of Sub-Kilowatt Electric Propulsion Technology to Enable Planetary Exploration and Commercial Mission Concepts Article 6 days ago 5 min read Why is Methane Seeping on Mars? NASA Scientists Have New Ideas Article 1 week ago 5 min read Hubble Goes Hunting for Small Main Belt Asteroids Article 2 weeks agoA new approach to dark matter could help us solve galactic anomalies
A new approach to dark matter could help us solve galactic anomalies
'Flash Gordon' returns to escape from a prison planet in new comic series
'Tiger stripes' on Saturn's moon Enceladus could reveal if its oceans are habitable
Astronomers finally know why stars born from the same cloud aren't identical twins
A Cold Brown Dwarf is Belching Methane Into Space
Brown dwarfs span the line between planets and stars. By definition, a star must be massive enough for hydrogen fusion to occur within its core. This puts the minimum mass of a star around 80 Jupiters. Planets, even large gas giants like Jupiter, only produce heat through gravitational collapse or radioactive decay, which is true for worlds up to about 13 Jovian masses. Above that, deuterium can undergo fusion. Brown dwarfs lay between these two extremes. The smallest brown dwarfs resemble gas planets with surface temperatures similar to Jupiter. The largest brown dwarfs have surface temperatures around 3,000 K and look essentially like stars.
Because of this, it can be difficult to study brown dwarfs, particularly ones that don’t orbit other stars. Without much reflected or emitted light, we can’t easily analyze their spectra to determine their composition. Fortunately, some brown dwarfs do emit radio light thanks to their strong magnetic fields.
Planets such as Earth and Jupiter have strong magnetic fields, and this means they can trap ionized particles such as hydrogen. These charged particles then spiral along the magnetic field lines until they collide with the planet’s upper atmosphere, generating glowing aurora. On Earth, we see them as the Northern Lights. For brown dwarfs, we can’t see the visible light of their aurora, but we can detect their radio glow.
Recently a team looked at the auroral light from a brown dwarf known as W1935. It is a cold brown dwarf 47 light-years from Earth with a surface temperature of just 200 °C. Within the spectra the team found light emissions from methane. While the presence of methane was expected in cold brown dwarfs, the fact that the methane emitted light was not. This means the atmosphere of W1935 likely has a thermal inversion, where the upper atmosphere is warmer than the lower layers.
This is true for the atmosphere of Earth but is driven by solar radiance. W1935 doesn’t orbit a star, so how can its upper atmosphere get so warm? One possible explanation is that the brown dwarf has an undetected small companion. This companion could be ejecting material similar to the way Saturn’s moon Enceleadus ejects water vapor. Once ionized in the vacuum of space, it would become trapped by the magnetic fields of W1935, eventually colliding with the brown dwarf’s upper atmosphere and giving it a bit of thermal heating.
This discovery shows that even the smallest brown dwarfs defy easy classification. Though they resemble planets, they may have their own planetary system like a star.
Reference: Faherty, Jacqueline K., et al. “Methane emission from a cool brown dwarf.” Nature 628.8008 (2024): 511-514.
The post A Cold Brown Dwarf is Belching Methane Into Space appeared first on Universe Today.
Innovation that Impacts All NASA Missions: Improving How We Engineer Our Systems
Download PDF: Innovation that Impacts All NASA Missions: Improving How We Engineer Our Systems
John F. Kennedy set the tone for NASA’s culture in 1961 during his famous speech on going to the Moon, “We choose to go to the Moon not because it’s easy, but because it’s hard; because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone…”
That culture has never faded, even across NASA’s diverse spectrum of missions. The continuous challenge to do what is hard or near impossible includes the requirement for innovation. Innovation is the importance of what we do, but also how we do it. With a goal of improving the way NASA’s workforce engineers its systems, the Systems Engineering (SE) Technical Discipline Team (TDT) has partnered with numerous facets of the NASA workforce to better enable innovation in how we work. Over the past year, three diverse teams made progress toward that goal by looking at the way we levy technical standards, improving understanding and integrated risk (cost, schedule, and technical), reducing project risk by better management of mass growth, and moving SE into the model based digital domain. A brief summary of each team’s efforts follows.
a). MBSE is being applied to help architect the ExMC, which is pushing the boundary of space medical systems to care for future astronauts. b). A proposed Mars sample return mission development project would benefit from using the NASA-endorsed ANSI/AIAA standard: Mass Properties Control for Space Systems
ExMC: Systems Analysis and Integration Using MBSE
Via its Model-Based Systems Engineering (MBSE) Infusion And Modernization Initiative (MIAMI), the NESC SE TDT partnered with the Human Research Program’s Exploration Medical Capability (ExMC) Element (https://www.nasa.gov/hrp/elements/exmc) at JSC. ExMC has adopted SE principles and tools (MBSE and the Systems Modeling Language) to develop an initial architecture and requirements for a future exploration medical system. MIAMI is assisting the ExMC work by providing an MBSE modeler who is matrixed to ExMC, one NASA MBSE Community of Practice (CoP) meeting per month dedicated to responding to ExMC’s needs, and any available/needed Agency MBSE infrastructure. In return, MIAMI is receiving modeling lessons learned, feedback to the MIAMI Leadership Team on available MBSE resources, and data needed to communicate MBSE successes and challenges to their SE TDT peers.The partnership has been mutually beneficial to ExMC, the SE TDT, and the greater NASA MBSE community. With MIAMI support, ExMC architected their system model, developed a model management plan, better defined their MBSE hiring and training needs, provided guidance to junior modelers, and developed ideas to push the boundaries of model usage.
As a return benefit, the MBSE community received a sample model architecture, an updated model management plan template, and valuable discussions at the MBSE CoP, where the ExMC presented ideas that had not been considered before. Ideas included the characteristics of good system modelers, how to manage model configuration, and using models with non-modeling tools. Notes from all these lively and well-attended CoP discussions are on the NASA Engineering Network MBSE website (https://nen.nasa.gov/web/mbse/). Beyond this, ExMC’s input on what will be necessary to grow NASA’s MBSE community and capability (e.g., modeler skillsets) continues to inform and ground in reality MIAMI’s recommendations to NASA’s Digital Transformation initiative.
For more information, contact Kerry McGuire, kerry.m.mcguire@nasa.gov.
NASA/JPL: Enterprise Approach to Mass Properties Control
In August 2019, a team of NESC and NASA subject matter experts (SME) issued a report regarding mass growth. It included recommendations to initiate the development and sustainment of an expanded mass growth database as an Agency resource and reforms in how programs and projects estimate, manage, and report mass properties based on the NASA-endorsed ANSI/AIAA S-120A-2015 [2019] standard, Mass Properties Control for Space Systems. The intent is to reap the benefits of a more common approach across NASA in managing and controlling mass growth and of using a common terminology among NASA Centers and its contractors. Historical mass growth data, consolidated in a single place, will help programs and projects in establishing Mass Growth Allowance (MGA) factors and mass margins above MGA that can reduce the risk of mass issues and potential cost overruns. To date, the NESC recommendations have resulted in major changes in mass management and control requirements and recommended best practices at JPL and other NASA Centers. Beyond Center-level actions, the NESC has engaged with the Office of the Chief Financial Officer to promote the use of the ANSI/AIAA standard’s terminology and calculations in future data collections for NPR 7120.5-mandated Cost Analysis Data Requirements documents.
For more information, contact Robert Shishko, robert.shishko@jpl.nasa.gov.
New approaches to streamlining design and constructions standards will benefit projects like the Gateway Power and Propulsion and Habitation and Logistics Outpost.
HALO: Modernized Application of Design & Construction Standards
The NASA Technical Standards Process Improvement pilot activity initiated by the Habitation and Logistics Outpost (HALO) Project seeks to improve the way that NASA levies and manages technical standards by 1) moving from document-centric to data-centric (databases) management of the requirements; 2) incorporating important attributes into the database so that applicability, tailoring, and information management is streamlined; and 3) providing technical recommendations on acceptable approaches for compliance evidence. The effort is a fleet-leader on how to streamline the standards deployment, assessment, and long-term verification process, while also improving the allocation of resources based on mission risk.
NASA Technical Fellows participated in this review and provided important input and support for the assessment of Design and Construction (D&C) standards for the HALO project. The approach “shredded” the requirements documents into a database of individual requirements with fields to populate describing the requirement type and compliance approach. Overall, the pilot activity is an important first step in properly assessing and flowing D&C standards to NASA’s contractors and partners. NESC systems engineering and integration SMEs reviewed the HALO pilot deployment activity for managing and implementing design and construction standards. The SMEs identified advantages and disadvantages of the pilot activity and offered suggestions for improving the standards streamlining effort in the future.
For more information, contact Jennifer Devolites, jennifer.devolites@nasa.gov
Private moon lander will carry Nokia's 4G cell network to the lunar surface this year
Measuring Exoplanetary Magnetospheres with the Square Kilometer Array
Life on Earth would not be possible without food, water, light, a breathable atmosphere and surprisingly, a magnetic field. Without it, Earth, and its inhabitants would be subjected to the harmful radiation from space making life here, impossible. If we find exoplanets with similar magnetospheres then those worlds may well be habitable. The Square Kilometer Array (SKA) which is still under construction should be able to detect such magnetospheres from radio emissions giving us real insight into our exoplanet cousins.
The magnetic field of Earth is the result of churning motion of liquid iron and nickel in the outer core. The resultant magnetic field has properties of a giant magnet with a north pole and a south pole and it extends from the core outward, enveloping the entire planet. The presence of the field stops harmful solar radiation and cosmic particles. Magnetic fields are not static though and it is not uncommon for them to flip, as has happened to our own magnetic field.
Since we have been hunting exoplanets (and to date, over 5,000 have been discovered) it has become clear that there are a good number of super sized gas gas giants. As our detection technology and methods improve, smaller, more Earth like planets are starting to be discovered. It is therefore not unreasonable to think that, among them, there may well be alien planets with magnetic fields making them, therefore good candidates for habitable environments.
Artist impression of glory on exoplanet WASP-76b. Credit: ESAUnderstanding exoplanet magnetic fields is in its infancy. So far, we have only explored magnetic fields around the planets in our Solar System. What we do know is that any planetary magnetic field emits radio signals due to the Electron Cyclotron Maser Instability mechanism. Sounds like something out of StarTrek or StarWars depending on your preference but either way, electromagnetic radiation is amplified by electrons that are trapped in the field. It is this amplified radiation that can be detected remotely IF we have a radio telescope with the capability.
A recent paper authored by Fatemeh Bagheri and team from the University of Texas explores whether it might be possible to detect the emissions using the Square Kilometre Array. The concept of the SKA is a radio interferometer with components in Australia and Africa and its headquarters in the UK. The international array of radio telescopes that are joined together electronically to operate as one collecting area of a square kilometre. It affords the ability to study the radio sky with higher sensitivity and resolution than ever before and it’s this, that Bagheri and team are focusing their attention.
Aerial image of the South African MeerKAT radio telescope, part of the Square Kilometer Array (SKA). Credit: SKAUsing NASA’s exoplanet archive data, they calculated the strength of radio signal from 80 confirmed planets. They took the planet’s radius, mass and orbital distance from the host star, along with the stars’ mass, radius and distance form us to estimate the signal from the magnetosphere. The results were promising and suggest that, according to their analysis exoplanets; Qatar-4 b, TOI-1278 b, and WASP-173 A b would indeed emit radio signals from their magnetosphere that the SKA could detect. Unfortunately we will have to wait until 2028 when SKA is operational but already, it seems researchers are lining up to use it and this piece of research in particular looks set not only to herald a greater understanding of exoplanets but also the possibility of life in the Universe.
Source : Exploring Radio Emissions from Confirmed Exoplanets Using SKA
The post Measuring Exoplanetary Magnetospheres with the Square Kilometer Array appeared first on Universe Today.
Genetically modified golden rice may yet succeed in the Philippines
Genetically modified golden rice may yet succeed in the Philippines
Toxic chemicals from car tyres can get into soil and contaminate food
Toxic chemicals from car tyres can get into soil and contaminate food
Lethal AI Weapons Are on the Rise. What’s Next?
Lethal autonomous weapons might reduce civilian casualties—or make catastrophic mistakes
There Are Safer Ways to Bed-Share with a Baby
For some parents, bed-sharing is the only way their baby can sleep. Rather than talking to parents about how to do it safely, we try to pretend it doesn’t exist
How Foreign Governments Sway Voters with Online Manipulation
Almost half of the world population heads to elections in 2024. To counter disinformation activities aimed against the voters on social media, we must first understand how they work
China's Moon Atlas Is the Most Detailed Ever Made
The Geologic Atlas of the Lunar Globe doubles the resolution of Apollo-era maps and will support the space ambitions of China and other countries