Astronomy Archives

October 17, 2023October 17, 2023 by David Dickinson

Comet Encke and the Halloween Fireballs of 2023

Will Comet 2/P Encke and the Taurid meteors ‘trick’ or ‘treat’ observers this year?

October and November are always great months to watch for meteors, and 2023 is no exception. This year provides a special reason to be vigilant, as the source of the infamous November Taurid Fireballs Comet 2P Encke reaches perihelion for 2023 on October 22^nd, at 0.34 Astronomical Units (AU) from the Sun.

October 15, 2023October 16, 2023 by Matt Williams

JWST Observes the Kuiper Belt: Sedna, Gonggong, and Quaoar

Artist's conception of Sedna, the TNO that orbits in the outer edges of the Solar System. Credit: NASA/JPL-Caltech

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.

October 13, 2023October 13, 2023 by Jon Voisey

The Milky Way’s Stolen Globular Clusters

Modern astronomy holds that all major galaxies (with the Milky Way as no exception) are the accumulation of numerous small mergers. Thus, it should be expected that some of the globular clusters that are now part of our galaxy are likely inherited from other galaxies which have been cannibalized by the Milky Way, or even stolen from intact companion galaxies such as the Magellanic Clouds.

Associations between these clusters and the various progenitors began in the 1990’s, but recent research is beginning to paint a more comprehensive picture on exactly what percentage of our globular clusters were stolen, and precisely which ones.

October 12, 2023October 12, 2023 by Carolyn Collins Petersen

A Simulation Predicts Where Astronomers Should Look to Find Intermediate-mass Black Holes

A simulated stellar cluster made using DRAGON-II simulations. Orange and yellow dots represent sunlike stars, while the blue dots indicate stars with masses of 20 to 300 times that of the Sun. The large white object in the center represents a star with a mass of about 350 solar masses, which will shortly collapse to form an intermediate-mass black hole. Courtesy M. Arca Sedda (GSSI) — A simulated stellar cluster made using DRAGON-II simulations. Orange and yellow dots represent sunlike stars, while the blue dots indicate stars with masses of 20 to 300 times that of the Sun. The large white object in the center represents a star with a mass of about 350 solar masses, which will shortly collapse to form an intermediate-mass black hole. Could this model explain intermediate-mass black holes? Courtesy M. Arca Sedda (GSSI)

The universe is swimming in black holes, from stellar mass to supermassive behemoths. But, there’s one class that remains elusive: the “middle child” class. These are called “intermediate-mass black holes (IMBH).” How numerous are they, how do they form, and where are they? To answer those questions, astronomers simulated possible formation scenarios.

October 12, 2023October 13, 2023 by Matt Williams

A Comprehensive Blueprint for the Settlement of Mars

Astronauts on Mars will need oxygen. There's oxygen in the atmosphere, but only small amounts. But there's lots of subterranean water on Mars, and that means there's lots of oxygen, too. (Credit: NASA)

Throughout the 20th century, multiple proposals have been made for the crewed exploration of Mars. These include the famed “Mars Project” by Werner von Braun, the “Mars Direct” mission architecture by Robert Zubrin and David Baker, NASA’s Mars Design Reference Mission studies, and SpaceX’s Mars & Beyond plan. By 2033, two space agencies (NASA and the CNSA) plan to commence sending crews and payloads to the Red Planet. These and other space agencies envision building bases there that could eventually lead to permanent settlements and the first “Martians.”

This presents several major challenges, not the least of which have to do with exposure to radiation, extreme temperatures, dust storms, low atmospheric pressure, and lower gravity. However, with the right strategies and technology, these challenges could be turned into opportunities for growth and innovation. In a recent paper, a Leiden University researcher offers a roadmap for a Martian settlement that leverages recent advancements in technology and offers solutions that emphasize sustainability, efficiency, and the well-being of the settlers.

October 12, 2023October 12, 2023 by Matt Williams

TRAPPIST-1 Has Flares. What Does This Mean for its Planets?

Most exoplanets orbit red dwarf stars because they're the most plentiful stars. This is an artist's illustration of what the TRAPPIST-1 system might look like from a vantage point near planet TRAPPIST-1f (at right). Credits: NASA/JPL-Caltech

The TRAPPIST-1 system continues to fascinate astronomers, astrobiologists, and exoplanet hunters alike. In 2017, NASA announced that this red dwarf star (located 39 light-years away) was orbited by no less than seven rocky planets – three of which were within the star’s habitable zone (HZ). Since then, scientists have attempted to learn more about this system of planets to determine whether they could support life. Of particular concern is the way TRAPPIST-1 – like all M-type (red dwarf) stars – is prone to flare-ups, which could have a detrimental effect on planetary atmospheres.

Using the James Webb Space Telescope (JWST), an international team of astrophysicists led by the University of Colorado Boulder (CU Boulder) took a closer look at this volatile star. As they describe in their paper (which recently appeared online), the Webb data was used to perform a detailed spectroscopic investigation of four solar flares bursting around TRAPPIST-1. Their findings could help scientists characterize planetary environments around red dwarf stars and measure how flare activity can affect planetary habitability.

October 12, 2023October 12, 2023 by Evan Gough

Astronomers See the Afterglow Where Two Ice Giant Planets Collided

This artist's illustration is a visualization of the huge, glowing planetary body produced by a planetary collision. In the foreground, fragments of ice and rock fly away from the collision and will later cross in between Earth and the host star which is seen in the background of the image. Image Credit: Mark Garlick

What would happen if two giant planets collided? It would be terrifying to behold if it happened in our Solar System. Imagine if Neptune and Uranus slammed into each other. Picture the chaos as a new super-heated object took their places, and clouds of debris blocked out the Sun. Think of the monumental destruction as objects are sent careening into each other.

Astronomers spotted the aftermath of a gigantic planetary collision like this in a distant solar system. From a safe distance, they were surprised and intrigued rather than terrified. Now, they intend to keep watching as the aftermath unfolds.

October 11, 2023October 11, 2023 by Matt Williams

China is Planning to Double the Size of its Space Station

Artist's rendering of the completed Tiangong space station. Credit: Shujianyang/Wikimedia

The International Space Station (ISS) will be retired in 2030 after more than thirty-two years of continuous service. Naturally, there are questions regarding what will replace this station, which has served as a bastion for vital research and inter-agency cooperation in space. In the past, China has indicated that their Tiangong (“heavenly palace”) space station will be a successor and rival to the ISS, offering astronauts from other nations an alternative platform to conduct research in Low Earth Orbit (LEO). As part of this plan, China recently announced plans to double the size of Tiangong in the coming years.

October 11, 2023October 11, 2023 by Evan Gough

The Closest Star Cluster Spat out an Extremely Massive White Dwarf

This image shows the Hyades star cluster, the nearest cluster to us. The Hyades cluster is well-studied due to its location. Why are there so few white dwarfs in the Hyades? Image Credit: NASA, ESA, and STScI.

The Hyades star cluster is only about 153 light-years away. At that short distance away, it’s visible with the unaided eye in the constellation Taurus. Its proximity gives professional astronomers an easier time observing it than many other objects of interest. Hyades contains hundreds of stars with similar ages—about 625 million years—similar metallicities and similar motions through space.

But something’s missing from the Hyades cluster: white dwarfs. There’s an apparent lack of them, with only eight of them in the cluster’s core. Where did they go?

October 10, 2023October 10, 2023 by Evan Gough

Seeing the Moment Planets Start to Form

ALMA captured this high-resolution image of the protoplanetary disk surrounding DG Taurus at a 1.3 mm wavelength. The young star is still embedded in its disk, and the smooth appearance, absent of ring-like structures, indicates a phase shortly before planets form. Credit: ALMA (ESO/NAOJ/NRAO), S. Ohashi, et al.

Nature makes few duplicates, and planets are as distinct from one another as snowflakes are. But planets all start out in the same circumstances: the whirling disks of material surrounding young stars. ALMA’s made great progress imaging these disks and the telltale gaps excavated by young, still-forming planets.

But new images from ALMA (Atacama Large Millimeter/submillimeter Array) show a star and disk so young that there are no telltale gaps in the disk. Is this the moment that planets start to form?