Calculating the distance to far-away objects, such as galaxy clusters and quasars, is difficult. But it is also critical to our understanding of how the universe evolves. Luckily, humanity has a trusty workhorse that has been collecting data for such calculations for decades—Hubble. It is by far the best telescope suited to the job, as described by a recent NASA press release about a distance measurement to a supernova in a nearby galaxy.
Continue reading “Only Hubble Could Make this Measurement of a Supernova”The JWST is Re-Writing Astronomy Textbooks
When the James Webb Space Telescope was launched at the end of 2021, we expected stunning images and illuminating scientific results. So far, the powerful space telescope has lived up to our expectations. The JWST has shown us things about the early Universe we never anticipated.
Some of those results are forcing a rewrite of astronomy textbooks.
Continue reading “The JWST is Re-Writing Astronomy Textbooks”Feast Your Eyes on 19 Face-On Spiral Galaxies Seen by Webb
If you’re fascinated by Nature, these images of spiral galaxies won’t help you escape your fascination.
These images show incredible detail in 19 spirals, imaged face-on by the JWST. The galactic arms with their multitudes of stars are lit up in infrared light, as are the dense galactic cores, where supermassive black holes reside.
Continue reading “Feast Your Eyes on 19 Face-On Spiral Galaxies Seen by Webb”A Solo Brown Dwarf Found With Auroras
Astronomers have used JWST to find a brown dwarf with polar auroras like the Earth, or Jupiter. This is surprising because the brown dwarf, dubbed W1935, is a free-floating object, meaning it isn’t part of another star system. Therefore, there’s no solar wind available to generate any Northern Lights. Instead, the auroras are seemingly generated from methane emissions in the planet’s atmosphere, interacting with the interstellar plasma. Another theory is that it perhaps has an active but unseen moon contributing to the emissions.
Continue reading “A Solo Brown Dwarf Found With Auroras”Why Was it Tricky to Know the Distances to Galaxies JWST Was Seeing?
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?”JWST Observes the Kuiper Belt: Sedna, Gonggong, and Quaoar
The Kuiper Belt, the vast region at the edge of our Solar System populated by countless icy objects, is a treasure trove of scientific discoveries. The detection and characterization of Kuiper Belt Objects (KBOs), sometimes referred to as Trans-Neptunian Objects (TNOs), has led to a new understanding of the history of the Solar System. The disposition of KBOs is an indicator of gravitational currents that have shaped the Solar System and reveal a dynamic history of planetary migrations. Since the late 20th century, scientists have been eager to get a closer look at KBOs to learn more about their orbits and composition.
Studying bodies in the outer Solar System is one of the many objectives of the James Webb Space Telescope (JWST). Using data obtained by Webb’s Near-Infrared Spectrometer (NIRSpec), an international team of astronomers observed three dwarf planets in the Kuiper Belt: Sedna, Gonggong, and Quaoar. These observations revealed several interesting things about their respective orbits and composition, including light hydrocarbons and complex organic molecules believed to be the product of methane irradiation.
Continue reading “JWST Observes the Kuiper Belt: Sedna, Gonggong, and Quaoar”Why Build Megastructures? Just Move Planets Around to Make Habitable Worlds
In 1960, Freeman Dyson proposed how advanced civilizations could create megastructures that enclosed their star, allowing them to harness all of their star’s energy and multiplying the habitable space they could occupy. In 2015, the astronomical community was intrigued when the star KIC 8462852 (aka. Tabby’s Star) began experiencing unexplained changes in brightness, leading some to speculate that the variations might be due to a megastructure. While the final analysis of the star’s light curve in 2018 revealed that the dimming pattern was more characteristic of dust than a solid structure, Tabby’s Star focused attention on the subject of megastructures and their associated technosignatures.
Dyson’s ideas were proposed at a time when astronomers were unaware of the abundance of exoplanets in our galaxy. The first confirmed exoplanet was not discovered until 1992, and that number has now reached 5,514! With this in mind, a team of researchers from Bangalore, India, recently released a paper that presents an alternative to the whole megastructure concept. For advanced civilizations looking for more room to expand, taking planets within their system – or capturing free-floating planets (FFP) beyond – and transferring them into the star’s circumsolar habitable zone (HZ) is a much simpler and less destructive solution.
Continue reading “Why Build Megastructures? Just Move Planets Around to Make Habitable Worlds”We Should Be Looking for Small, Hot Dyson Spheres
In 1960, legendary physicist Freeman Dyson published his seminal paper “Search for Artificial Stellar Sources of Infrared Radiation,” wherein he proposed that there could be extraterrestrial civilizations so advanced that they could build megastructures large enough to enclose their parent star. He also indicated that these “Dyson Spheres,” as they came to be known, could be detected based on the “waste heat” they emitted at mid-infrared wavelengths. To this day, infrared signatures are considered a viable technosignature in the Search for Extraterrestrial Intelligence (SETI).
So far, efforts to detect Dyson Spheres (and variation thereof) by their “waste heat” signatures have come up empty, leading some scientists to recommend tweaking the search parameters. In a new paper, astronomy and astrophysics Professor Jason T. Wright of the Center for Exoplanets and Habitable Worlds and the Penn State Extraterrestrial Intelligence Center (PSTI) recommends that SETI researchers refine the search by looking for indications of activity. In other words, he recommends looking for Dyson Spheres based on what they could be used for rather than just heat signatures.
Continue reading “We Should Be Looking for Small, Hot Dyson Spheres”The Suspense is Killing Us. The Next Planet in the TRAPPIST System Gets the JWST Treatment
The TRAPPIST-1 system is easily the most exciting collection of exoplanets ever discovered by astronomers. The system contains seven rocky planets orbiting an ultracool red dwarf star 40 light-years from Earth. Several of the planets are in the star’s habitable zone.
With the James Webb Space Telescope’s ability to detect and study the atmospheres of distant planets orbiting other stars, data on the TRAPPIST planets have been highly anticipated. Astronomers have now released detailed information about the second planet, TRAPPIST-1 c, theorized to be a Venus-like world. Unlike Venus, however, JWST failed to detect any trace of a thick carbon dioxide atmosphere.
Continue reading “The Suspense is Killing Us. The Next Planet in the TRAPPIST System Gets the JWST Treatment”Could We Resurrect the Spitzer Space Telescope?
NASA’s Spitzer Space Telescope served the astronomy community well for 16 years. From its launch in 2003 to the end of its operations in January 2020, its infrared observations fuelled scientific discoveries too numerous to list.
Infrared telescopes need to be kept cool to operate, and eventually, it ran out of coolant. But that wasn’t the end of the mission; it kept operating in ‘warm’ mode, where observations were limited. Its mission only ended when it drifted too far away from Earth to communicate effectively.
Now the US Space Force thinks they can reboot the telescope.
Continue reading “Could We Resurrect the Spitzer Space Telescope?”