Exoplanets – worlds of other suns

weatheriscool
Posts: 12964
Joined: Sun May 16, 2021 6:16 pm

Re: Exoplanets – worlds of other suns

Post by weatheriscool »

GAIA mission been extended until middle of 2025 it will be 11 years of scientific mission until there maybe 100,000 planets until the end of processing the data in 2030 who knows…

https://sci.esa.int/web/director-desk/- ... e-missions
weatheriscool
Posts: 12964
Joined: Sun May 16, 2021 6:16 pm

Re: Exoplanets – worlds of other suns

Post by weatheriscool »

A super-Earth and a mini-Neptune near the 2:1 MMR straddling the radius valley around the nearby mid-M dwarf TOI-2096
https://arxiv.org/abs/2303.08174
weatheriscool
Posts: 12964
Joined: Sun May 16, 2021 6:16 pm

Re: Exoplanets – worlds of other suns

Post by weatheriscool »

Small stars may host bigger planets than previously thought
https://phys.org/news/2023-03-small-sta ... anets.html
by University College London
Stars with less than half the mass of our sun are able to host giant Jupiter-style planets, in conflict with the most widely accepted theory of how such planets form, according to a new study led by UCL (University College London) and University of Warwick researchers.

Gas giants, like other planets, form from disks of material surrounding young stars. According to core accretion theory, they first form a core of rock, ice and other heavy solids, attracting an outer layer of gas once this core is sufficiently massive (about 15 to 20 times that of Earth).

However, low-mass stars have low-mass disks that, models predict, would not provide enough material to form a gas giant in this way, or at least not quickly enough before the disk breaks up.

In the study, accepted for publication in the Monthly Notices of the Royal Astronomical Society (MNRAS), researchers looked at 91,306 low-mass stars, using observations from NASA's Transiting Exoplanet Survey Satellite (TESS), and in 15 cases found dips in the brightness of the light corresponding to a gas giant passing in front of the star.

Five out of the 15 potential giant planets have since been confirmed as planets using independent methods. One of these confirmed planets orbits a star that is a fifth of the mass of the sun—which would not be possible according to planet formation models.
weatheriscool
Posts: 12964
Joined: Sun May 16, 2021 6:16 pm

Re: Exoplanets – worlds of other suns

Post by weatheriscool »

James Webb telescope detects dust storm on distant world
https://www.bbc.com/news/science-environment-65040983
A raging dust storm has been observed on a planet outside our Solar System for the first time.

It was detected on the exoplanet known as VHS 1256b, which is about 40 light-years from Earth.

It took the remarkable capabilities of the new James Webb Space Telescope (JWST) to make the discovery.

The dust particles are silicates - small grains comprising silicon and oxygen, which form the basis of most rocky minerals.

But the storm detected by Webb isn't quite the same phenomenon you would get in an arid, desert region on our planet. It's more of a rocky mist.

"It's kind of like if you took sand grains, but much finer. We're talking silicate grains the size of smoke particles," explained Prof Beth Biller from the University of Edinburgh and the Royal Observatory Edinburgh, UK.

"That's what the clouds on VHS 1256b would be like, but a lot hotter. This planet is a hot, young object. The cloud-top temperature is maybe similar to the temperature of a candle flame," she told BBC News.
User avatar
wjfox
Site Admin
Posts: 8732
Joined: Sat May 15, 2021 6:09 pm
Location: London, UK
Contact:

Re: Exoplanets – worlds of other suns

Post by wjfox »

weatheriscool
Posts: 12964
Joined: Sun May 16, 2021 6:16 pm

Re: Exoplanets – worlds of other suns

Post by weatheriscool »

Webb space telescope measures the temperature of a rocky exoplanet
https://phys.org/news/2023-03-webb-spac ... rocky.html
by European Space Agency
An international team of researchers has used the NASA/ESA/CSA James Webb Space Telescope to measure the temperature of the rocky exoplanet TRAPPIST-1 b. The measurement is based on the planet's thermal emission: heat energy given off in the form of infrared light detected by Webb's Mid-Infrared Instrument (MIRI).

The result indicates that the planet's dayside has a temperature of about 500 Kelvin (roughly 230°C), and suggests that it has no significant atmosphere. This is the first detection of any form of light emitted by an exoplanet as small and as cool as the rocky planets in our own solar system. The result marks an important step in determining whether planets orbiting small active stars like TRAPPIST-1 can sustain atmospheres needed to support life. It also bodes well for Webb's ability to characterize temperate, Earth-sized exoplanets using MIRI.

"These observations really take advantage of Webb's mid-infrared capability," said Thomas Greene, an astrophysicist at NASA's Ames Research Center and lead author on the study published today in the journal Nature. "No previous telescopes have had the sensitivity to measure such dim mid-infrared light."
Image
User avatar
Time_Traveller
Posts: 2096
Joined: Sun May 16, 2021 4:49 pm
Location: Clermont, Indiana, USA, October 7th 2019 B.C.E

Re: Exoplanets – worlds of other suns

Post by Time_Traveller »

Discovering the Most Terrifying Planets in the Universe (VIDEO)
March 30, 2023

Have you ever looked up at the night sky and wondered what kind of planets are oᴜt there? Well, let me tell you, not all of them are the idyllic, habitable worlds we dream of. In fact, some of the planets we’ve discovered are downright teггіfуіпɡ. From never-ending nights to raining glass and planets being devoured by their own stars, the universe is full of surprises – and not all of them are pleasant.
"We all have our time machines, don't we. Those that take us back are memories...And those that carry us forward, are dreams."

-H.G Wells.
weatheriscool
Posts: 12964
Joined: Sun May 16, 2021 6:16 pm

Re: Exoplanets – worlds of other suns

Post by weatheriscool »

Repeating Radio Signal Leads Astronomers to an Earth-size Exoplanet
Source: CNN

Astronomers have detected a repeating radio signal from an exoplanet and the star that it orbits, both located 12 light-years away from Earth. The signal suggests that the Earth-size planet may have a magnetic field and perhaps even an atmosphere.

Earth’s magnetic field protects the planet’s atmosphere, which life needs to survive, by deflecting energetic particles and plasma that stream out from the sun. Finding atmospheres around planets located outside of our solar system could point to other worlds that potentially have the ability to support life.

Scientists noticed strong radio waves coming from the star YZ Ceti and the rocky exoplanet that orbits it, called YZ Ceti b, during observations using the Karl G. Jansky Very Large Array of telescopes in New Mexico. The researchers believe the radio signal was created by interactions between the planet’s magnetic field and the star.

A study detailing the findings was published Monday in the journal Nature Astronomy.
Read more: https://www.cnn.com/2023/04/04/world/ex ... index.html
weatheriscool
Posts: 12964
Joined: Sun May 16, 2021 6:16 pm

Re: Exoplanets – worlds of other suns

Post by weatheriscool »

Coherent radio bursts from known M-dwarf planet-host YZ Ceti
https://www.nature.com/articles/s41550- ... tastronTWT

Conclusions wrote:
Using simple Poisson statistics, the probability of seeing at least one event in the 3.6 h associated with epoch 5 is ~24%. By contrast, the probability of seeing one burst, on two separate occasions within 2 h of a given phase (a 4 h window) is only 5.1%—small but insufficient as conclusive evidence. It is thus plausible that the bursts could have no association with the planetary system and be a normal part of the radio stellar activity of slowly rotating M dwarfs, which is not yet well studied. The mechanisms powering the emission remain inconclusive, and we thus categorize YZ Cet as an SPI candidate, requiring further follow-up to discern the nature of the radio bursts.
weatheriscool
Posts: 12964
Joined: Sun May 16, 2021 6:16 pm

Re: Exoplanets – worlds of other suns

Post by weatheriscool »

LHS 475 b: A Venus-sized Planet Orbiting a Nearby M Dwarf
https://arxiv.org/abs/2304.01920
Quote :
Based on photometric observations by TESS, we present the discovery of a Venus-sized planet transiting LHS 475, an M3 dwarf located 12.5 pc from the Sun. The mass of the star is 0.274±0.015 MSun. The planet, originally reported as TOI 910.01, has an orbital period of 2.0291025±0.0000020 days and an estimated radius of 0.955±0.053 REarth. We confirm the validity and source of the transit signal with MEarth ground-based follow-up photometry of five individual transits. We present radial velocity data from CHIRON that rule out massive companions. In accordance with the observed mass-radius distribution of exoplanets as well as planet formation theory, we expect this Venus-sized companion to be terrestrial, with an estimated RV semi-amplitude close to 1.0 m/s. LHS 475 b is likely too hot to be habitable but is a suitable candidate for emission and transmission spectroscopy.
Post Reply