The early universe was a much different place than our own, and astronomers do not fully understand how baby stars grew up in that environment. And while instruments like the James Webb Space Telescope will pierce back into the earliest epochs of star formation, we don’t always have to work so hard – there may be clues closer to home.
Continue reading “The First cry From a Brand new Baby Star”A new way to Discover Planets? Astronomers Detect an Exoplanet by Seeing its Trojan Belts
Although we have found thousands of exoplanets in recent years, we really only have three methods of finding them. The first is to observe a star dimming slightly as a planet passes in front of it (transit method). The second is to measure the wobble of a star as an orbiting planet gives it a gravitational tug (Doppler method). The third is to observe the exoplanet directly. Now a new study in the Astrophysical Journal Letters has a fourth method.
Continue reading “A new way to Discover Planets? Astronomers Detect an Exoplanet by Seeing its Trojan Belts”The History of the Sun is Written on the Moon
If you want to learn about the history of the Sun, then look no further than the Moon. That’s the recommendation of a team of scientists who hope to harness future Artemis lunar missions to help understand the life history of our home star.
Continue reading “The History of the Sun is Written on the Moon”Hubble Sees a Spiral Galaxy With a Supermassive Black Hole Feasting at its Center
Even after thirty years, and with next-generation telescopes (like the James Webb) hogging all the attention, the Hubble Space Telescope still manages to inspire. Recently, Hubble acquired a breathtaking image of NGC 1961, an intermediate spiral galaxy measuring 220,000 light years in diameter and located about 180 million light-years away in the constellation Camelopardalis. Intermediate spiral galaxies are so-named because they are between “barred” and “unbarred” spiral galaxies, which means they don’t have a well-defined bar of stars at their centers.
The data used to create this image came from two sources, the first being a study of previously-unobserved objects belonging to the Atlas of Peculiar Galaxies (or “Arp galaxies,” named after astronomer Halton Arp). The second source consisted of observations made of the progenitors and explosions of a variety of supernovae. Between 1998 and 2021, four supernovae were observed in NGC 1961 (SN 1998eb, SN 2001is, SN 2013cc, and SN 2021vaz), making it a high-value target for study.
The resulting image captures the dusty spiral arms, bright, hot star-forming regions of NGC 1961 and the galaxy’s glowing center that manages to outshine all the stars in its disk. This is an example of an active galactic nucleus (AGN), where the central region emits tremendous amounts of energy because it contains a supermassive black hole (SMBH) that feeds on the surrounding dust, gas, and stars in the core region.
Many AGNs have been observed emitting bright jets of hot dust and gas that are accelerated to relativistic speeds (a fraction of the speed of light). These jets can be seen millions of light-years away and play an important role in a galaxy’s evolution. NGC 1961 is a fairly common type of AGN that shines brightly but emits low-energy-charged particles. It just goes to show that the old workhorses never lose their mojo! They just keep on delivering well into their later years!
Further Reading: NASA
A Galaxy With Ten Times the Mass of the Milky Way is Preparing to Become a Quasar
One of the fundamental questions in astronomy is how galaxies formed over 13 billion years ago and have evolved ever since. A common feature that astronomers have noted is that most galaxies appear to have supermassive black holes (SMBHs) at their center – like Sagittarius A*, the ~4 million solar mass SMBH at the center of the Milky Way. These monster black holes occasionally swallow up nearby gas, dust, and stars and emit excess energy as powerful relativistic jets. This phenomenon, where the center of a galaxy outshines the stars in the disk, is known as an Active Galactic Nucleus (AGN) or quasar.
In a recent study, an international team of astronomers led by the European Southern Observatory (ESO) discovered a galaxy in the early Universe that could reveal more about this evolution. Using the Very Large Telescope (VLT) and the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, they observed a swarm of galaxies orbiting a very bright and vigorously star-forming galaxy in the early Universe. These observations provide fresh insight into how exceptionally bright galaxies grow and evolve into quasars and emit powerful jets of light across the observable Universe.
Continue reading “A Galaxy With Ten Times the Mass of the Milky Way is Preparing to Become a Quasar”Galactic Superwinds From Supernovae and Newly-Forming Stars Shape a Galaxy’s Early Development
Astronomers have long believed that supernovae and stellar winds drive outflows from galaxies known as superwinds. New research suggests that they may instead be due to a ring of nuclear fire.
Continue reading “Galactic Superwinds From Supernovae and Newly-Forming Stars Shape a Galaxy’s Early Development”There Could be as Many Water Worlds as Earths in the Milky Way
On July 12th, 2022, NASA released the first images acquired by the James Webb Space Telescope, which were taken during its first six months of operation. Among its many scientific objectives, Webb will search for smaller, rocky planets that orbit closer to their suns – especially dimmer M-type (red dwarf) stars, the most common in the Universe. This will help astronomers complete the census of exoplanets and gain a better understanding of the types of worlds that exist out there. In particular, astronomers are curious about how many terrestrial planets in our galaxy are actually “water worlds.”
These are rocky planets that are larger than Earth but have a lower density, which suggests that volatiles like water make up a significant amount (up to half) of their mass-fraction. According to a recent study by researchers from the University of Chicago and the Instituto de Astrofísica de Canarias (IAC), water worlds may be just as common as “Earth-like” rocky planets. These findings bolster the case for exoplanets that are similar to icy moons in the Solar System (like Europa) and could have significant implications for future exoplanet studies and the search for life in our Universe.
Continue reading “There Could be as Many Water Worlds as Earths in the Milky Way”The Tonga Eruption Produced a 90-Meter Tsunami
The gigantic underwater Tonga volcano eruption event captured the world’s attention in January of this year. People from around the world marveled at the satellite imagery of this awesome demonstration of nature’s destructive capability. But only now are we learning that the volcano triggered something else – a tsunami wave up to 90m tall, nine times higher than the tsunamis generated by earthquakes.
Continue reading “The Tonga Eruption Produced a 90-Meter Tsunami”Meet the New Vespera Telescope From Vaonis
The Vespera telescope offers power and portability in a small deep-sky imaging package.
A great new telescope just got smaller and more portable. The French-based company Vaonis released its newest addition to their ‘smartscope’ family this week: the Vespera telescope. The small pill-shaped instrument joins the Stellina and the (forthcoming) Hyperia line, offering a lower price point and backpack portability without a compromise in quality.
Continue reading “Meet the New Vespera Telescope From Vaonis”Massive Stars don’t Always Grow Their own Planets. Sometimes They Steal Them
Recently astronomers have discovered Jupiter-sized planets orbiting at extremely large distances from giant stars. How can these stars end up with such big planets at such extreme orbits? A team of researchers has proposed that the answer is that the stars steal those planets from their neighbors.
Continue reading “Massive Stars don’t Always Grow Their own Planets. Sometimes They Steal Them”