Astronomy

With an injection of rat cells, mouse brains that were genetically engineered to be unable to smell could detect odors and even track down an Oreo cookie stash

“Energy independence” doesn’t mean what politicians think it means

China reportedly plans to launch its Chang'e 6 sample-return mission toward the moon's mysterious far side on Friday (May 3).

Climate change means many tree species planted today in Europe won’t survive to the end of the century, but English oaks could thrive in many areas

Climate change means many tree species planted today in Europe won’t survive to the end of the century, but English oaks could thrive in many areas

Boeing Starliner's 1st astronaut crew continues their training, even in quarantine. After finishing a big dress rehearsal on April 26, practice continues ahead of the scheduled May 6 launch to the ISS.

A giant impact likely formed Pluto's heart-shaped basin, Sputnik Planitia. A big chunk of the impactor’s core might still be buried under the ice.

The post A Cosmic Arrow Pierced Pluto's Heart — Is It Still There Beneath the Surface? appeared first on Sky & Telescope.

NASA astronauts Barry "Butch" Wilmore and Suni Williams are slated to launch on Boeing’s first crewed test flight of its Starliner capsule, flying to the International Space Station on May 6.

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.

Cosmological puzzles are tempting astronomers to rethink our simple picture of the universe – and ask whether dark matter is even stranger than we thought

Cosmological puzzles are tempting astronomers to rethink our simple picture of the universe – and ask whether dark matter is even stranger than we thought

Cosmological puzzles are tempting astronomers to rethink our simple picture of the universe – and ask whether dark matter is even stranger than we thought

Cosmological puzzles are tempting astronomers to rethink our simple picture of the universe – and ask whether dark matter is even stranger than we thought

A preview of Mad Cave Studios' new "Flash Gordon" comic book series coming in July.

A new model of Enceladus "tiger stripe" fractures and their connection with the moon of Saturn's ice geysers and subsurface oceans could have implications for its ability to support life.

Astronomers finally know why giant binary stars born from the same collapsing cloud of gas and dust can be "non-identical twins" with different characteristics and planetary systems.

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.

Nokia is developing a LTE/4G communications system for the moon, and its first piece of the network might launch as soon as late this year.

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: ESA

Understanding 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: SKA

Using 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.

A court in the Philippines revoked the permit to grow rice genetically modified to boost vitamin A, but the government is expected to appeal against the decision