About 1,000 light years away in the constellation Perseus, the stellar nursery designated NGC 1333 is emerging as a priority target for astronomers planning to use the James Webb Space Telescope. Brown dwarfs come into play in the planned work, as do the free-floating 'rogue' planets we discussed recently. For NGC 1333 is a compact, relatively nearby target, positioned at the edge of a star-forming molecular cloud. It's packed with hundreds of young stars, many of them hidden from view by dust, a venue in which to observe star formation in action. Hoping to learn more about very low mass objects, Aleks Scholz (University of St Andrews, UK) lays out plans for using JWST to chart the distinctions between objects that emerge out of gravitational collapse of gas and dust clouds, and objects that grow through accretion inside a circumstellar disk. Says Scholz: "The least massive brown dwarfs identified so far are only five to 10 times heftier than the planet Jupiter. We don't yet know...

Hard to believe that Fast Radio Bursts (FRBs) were only discovered in 2007, as it seems we've been puzzled by them for a lot longer. Thus far about 140 FRBs have been detected, but now we have news that the Canadian Hydrogen Intensity Mapping Experiment (CHIME) has pulled in a total of 535 new fast radio bursts in its first year of operation between 2018 and 2019. The catalog growing from this work was presented this week at the annual meeting of the American Astronomical Society. "Before CHIME, there were less than 100 total discovered FRBs; now, after one year of observation, we've discovered hundreds more," says CHIME member Kaitlyn Shin, a graduate student in MIT's Department of Physics. "With all these sources, we can really start getting a picture of what FRBs look like as a whole, what astrophysics might be driving these events, and how they can be used to study the universe going forward." Image: The large radio telescope CHIME, pictured here, has detected more than 500...

If we assume that the Oort Cloud, that enveloping shroud of comets that surrounds our Solar System and extends to 100,000 AU or beyond, is a common feature of stellar systems, then it’s conceivable that objects are interchanged between the Sun and Alpha Centauri where the two clouds approach each other. That makes for the ‘slow boat to Centauri’ concept I’ve written about before, where travel between the stars essentially mines resources along the way in migrations lasting thousands of years. The resulting society would not be planet-oriented. When the Dutch astronomer Jan Hendrik Oort deduced the cloud’s existence, he theorized that there was an inner, disk-shaped component as well as an outer, spherical cloud, as shown in the image below. The outer cloud is only loosely bound to the Sun, making the interchange of cometary materials between stars a likely event over the aeons, while gravitational nudges from passing stars can dislodge comets in the other direction as well, causing...

The galaxy UGC 10738 resonates with the galaxy described yesterday -- BRI 1335-0417 -- in that it raises questions about how spiral galaxies form. In fact, the team working on UGC 10738 thinks it goes a long way toward answering them. That's because what we see here is a cross-sectional view of a galaxy much like the Milky Way, one that has both 'thick' and 'thin' disks like ours. The implication is that these structures are not the result of collisions with smaller galaxies but typical formation patterns for all spirals. Nicholas Scott and Jesse van de Sande (ASTRO 3D/University of Sydney) led the study, which used data from the European Southern Observatory's Very Large Telescope in Chile. As you can see from the image below, the galaxy, some 320 million light years away, presents itself to us edge on, offering a cross-section of its structure. Key to the work was the team's assessment of stellar metallicity, as van de Sande explains: "Using an instrument called the multi-unit...

My fascination with the earliest era of star and galaxy formation leads me to a new paper on an intriguing find. The authors describe the distant object BRI 1335-0417 as "an intensely star-forming galaxy," and its image as captured by the Atacama Large Millimeter/submillimeter Array (ALMA) is striking. This is a galaxy that formed a mere 1.4 billion years after the Big Bang, making it the most ancient galaxy with spiral structure ever observed. Spirals make up perhaps 70 percent of the galaxies in our catalogs, but how they form is an open question. Indeed, the proportion of spiral galaxies declines the further back in the evolution of the universe we observe. The spiral structure observed here extends 15,000 light years from the center of the galaxy (about a third the size of the Milky Way), while the total mass of stars and interstellar matter roughly equals our own galaxy. Image: ALMA image of a galaxy BRI1335-0417 in the Universe 12.4 billion years ago. ALMA detected emissions...