Space and astronomy news
The JWST has directly imaged its first exoplanet, a temperate super Jupiter only about 12 light-years away from Earth. It could be the oldest and coldest planet ever detected.
Continue reading “Webb Directly Images a Jupiter-Like Planet”
One of the chief objectives of the James Webb Space Telescope (JWST) is to study the formation and evolution of the earliest galaxies in the Universe, which emerged more than 13 billion years ago. To this end, scientists must identify galaxies from different cosmological epochs to explore how their properties have changed over time. This, in turn, requires precise dating techniques so astronomers are able to determine when (in the history of the Universe) an observed galaxy existed. The key is to measure the object’s redshift, which indicates how long its light has been traveling through space.
This is the purpose of the Cosmic Evolution Early Release Science Survey (CEERS), a collaborative research group that analyzes Webb data to learn more about galactic evolution. These galaxies are known as “high-redshift,” meaning that their light emissions are redshifted all the way into the infrared spectrum. Galaxies that existed ca. 13 billion years ago can only be observed in the near-infrared spectrum, which is now possible thanks to Webb’s Near-Infrared Camera (NIRCam). Even so, obtaining accurate redshift measurements from such distant galaxies is a very tricky, and requires advanced techniques.
Continue reading “Why Was it Tricky to Know the Distances to Galaxies JWST Was Seeing?”
In a recent study published in the Monthly Notices of the Royal Astronomical Society, a team of international researchers examined exoplanet TOI-4860 b, which is located approximately 80 parsecs (261 light-years) from Earth and has an orbital period of approximately 1.52 days around a low-mass star, or a star smaller than our Sun. Exoplanets orbiting so close to their parent stars aren’t uncommon and commonly known as “hot Jupiters”.
However, TOI-4860 b is unique due its relative size compared to its parent star, along with its lower surface temperatures compared to “hot Jupiters” and possessing large amounts of heavy elements. These attributes are why researchers are classifying TOI-4680 b as a “warm Jupiter”, and could challenge traditional planetary systems formation models while offering new insights into such processes, as well.
Continue reading “This Jupiter-Sized Exoplanet is Unusual for Several Reasons”
SpaceX’s Starlink satellite system has been in the news lately for both good and ill. The “Mega-constellation” of around 2,800 satellites added another 53 satellites to its roster just last week. But while it might one day provide high-speed internet for the whole of humanity, it is already causing a massive headache for one particular slice of humanity – astronomers. Starlink satellites are reflective due to the solar panels they need to power themselves.
Continue reading “With Better Communication, Astronomers and Satellites can co-Exist”
With exoplanet discoveries coming at us several times a month, finding these worlds is a hot field of research. Once the planets are found and confirmed, however, there’s a lot more that has to be done to understand them. What are they made of? How habitable are they? What are their atmospheres like? These are questions we are only beginning to understand.
One long-standing exoplanet researcher argues that we don’t know very much about about alien planet atmospheres, as an example. Princeton University’s Adam Burrows says that not only is our understanding at an infancy, but the media and scientists overhype information based on very little data.
“Exoplanet research is in a period of productive fermentation that implies we’re doing something new that will indeed mature,” Burrows stated in a story posted on Princeton Journal Watch. “Our observations just aren’t yet of a quality that is good enough to draw the conclusions we want to draw.”
Burrow’s skepticism comes from how information on exoplanet atmospheres is collected. That uses a method called low-resolution photometry, which shows changes in light and radiation emitted from an object such as a planet. This could be affected by things such as a planet’s rotation and cloud cover.
Burrows’ solution is to use spectrometry, which can glean physical information through looking at light spectra, but that would be a challenge given the existing exoplanet-seeking infrastructure in space and on Earth uses telescopes that generally rely on other methods.
What do you think of his conclusions? Leave your thoughts in the comments. For more information, read the full article in Princeton Journal Watch, the study in Proceedings of the National Academy or the preprint version on Arxiv.
A simple, yet elegant method of measuring the surface gravity of a star has just been discovered. These computations are important because they reveal stellar physical properties and evolutionary state – and that’s not all. The technique works equally well for estimating the size of hundreds of exoplanets. Developed by a team of astronomers and headed by Vanderbilt Professor of Physics and Astronomy, Keivan Stassun, this new technique measures a star’s “flicker”. Continue reading “Flicker… A Bright New Method of Measuring Stellar Surface Gravity”