Astronomy Archives

October 18, 2024October 19, 2024 by David Dickinson

Review: Unistellar’s New Odyssey Pro Smart Telescope

Unistellar’s new Odyssey Pro telescope offers access to deep-sky astrophotography in a small portable package.

Access to the night sky has never been simpler. The last half decade has seen a revolution in backyard astronomy, as ‘smartscopes’—telescopes controlled by smartphone applications—have come to the fore. These offer an easy entry into basic deep sky astrophotography even from bright urban skies, albeit at a higher price point versus traditional telescopes on the market. We’ve reviewed units from Vaonis and Unistellar before, as well as wrote commentary on the rise of the whole smartscope movement. Now, Unistellar has a new entry on the market in 2024: the Odyssey Pro.

October 17, 2024October 19, 2024 by Matt Williams

Establishing a New Habitability Metric for Future Astrobiology Surveys

An illustration of the variations among the more than 5,000 known exoplanets discovered since the 1990s. Could their stars' metallicity play a role in making them habitable to life? Credit: NASA/JPL-Caltech

The search for exoplanets has grown immensely in recent decades thanks to next-generation observatories and instruments. The current census is 5,766 confirmed exoplanets in 4,310 systems, with thousands more awaiting confirmation. With so many planets available for study, exoplanet studies and astrobiology are transitioning from the discovery process to characterization. Essentially, this means that astronomers are reaching the point where they can directly image exoplanets and determine the chemical composition of their atmospheres.

As always, the ultimate goal is to find terrestrial (rocky) exoplanets that are “habitable,” meaning they could support life. However, our notions of habitability have been primarily focused on comparisons to modern-day Earth (i.e., “Earth-like“), which has come to be challenged in recent years. In a recent study, a team of astrobiologists considered how Earth has changed over time, giving rise to different biosignatures. Their findings could inform future exoplanet searches using next-generation telescopes like the Habitable Worlds Observatory (HWO), destined for space by the 2040s.

October 17, 2024October 17, 2024 by Matt Williams

Astronomers Solve the Mystery of the Famed Brown Dwarf That is Too Bright: It’s Twins!

This artwork highlights a pair of recently uncovered brown dwarf twins, named Gliese 229 Ba and Gliese 229 Bb. Credit: K. Miller/R. Hurt (Caltech/IPAC)

In 1995, Caltech researchers at the Institute’s Palomar Observatory first observed what appeared to be a brown dwarf orbiting Gliese 229 – a red dwarf star located about 19 light-years from Earth. Since then, this brown dwarf (Gliese 229 B) has mystified astronomers because it appeared too dim for its mass. With 70 times the mass of Jupiter, it should have been brighter than what telescopes had observed. However, a Caltech-led international team of astronomers recently solved the mystery by determining that the brown dwarf is a pair of closely orbiting twins!

October 13, 2024October 13, 2024 by Matt Williams

New Research Could Help Resolve the “Three-Body Problem”

Zine Tseng as Chinese radio astronomer, sitting at control panel for antenna — Zine Tseng plays a Chinese radio astronomer in "3 Body Problem." (Credit: Ed Miller / Netflix © 2024)

Perhaps you’ve heard of the popular Netflix show and the science fiction novel on which it is based, The Three-Body Problem, by Chinese science fiction author Liu Cixin. The story’s premise is a star system where three stars orbit each other, which leads to periodic destruction on a planet orbiting one of them. As Isaac Newton described in his Philosophiæ Naturalis Principia Mathematica, the interaction of two massive bodies is easy to predict and calculate. However, the interaction of three bodies leads is where things become unpredictable (even chaotic) over time.

This problem has fascinated scientists ever since and remains one of the most famous unsolved mysteries in mathematics and theoretical physics. The theory states that the interaction of three gravitationally bound objects will evolve chaotically and in a way that is completely detached from their initial positions and velocities. However, in a recent study, an international team led by a researcher from the Niels Bohr Institute ran millions of simulations that showed “isles of regularity in a sea of chaos.” These results indicate that there could be a solution, or at least some predictability, to the Three-Body Problem.

October 13, 2024October 13, 2024 by Matt Williams

Webb Observations Shed New Light on Cosmic Reionization

A simulation of galaxies during the era of deionization in the early Universe. Credit: M. Alvarez, R. Kaehler, and T. AbelCredit: M. Alvarez, R. Kaehler, and T. Abel

The “Epoch of Reionization” was a critical period for cosmic evolution and has always fascinated and mystified astronomers. During this epoch, the first stars and galaxies formed and reionized the clouds of neutral hydrogen that permeated the Universe. This ended the Cosmic Dark Ages and led to the Universe becoming “transparent,” what astronomers refer to as “Cosmic Dawn.” According to our current cosmological models, reionization lasted from 380,000 to 1 billion years after the Big Bang. This is based on indirect evidence since astronomers have been unable to view the Epoch of Reionization directly.

Investigating this period was one of the main reasons for developing the James Webb Space Telescope (JWST), which can pierce the veil of the “dark ages” using its powerful infrared optics. However, observations provided by Webb revealed that far more galaxies existed in the early Universe than previously expected. According to a recent study, this suggests that reionization may have happened more rapidly and ended at least 350 million years earlier than our models predict. Once again, the ability to peer into the early Universe has produced tensions with prevailing cosmological theories.

October 12, 2024October 14, 2024 by Matt Williams

A Possible Exomoon Could be Volcanic, like Jupiter’s Moon Io

New NASA-led research suggests a sodium cloud seen around the exoplanet WASP-49 b might be created by a volcanic moon, which is depicted in this artist’s concept. Jupiter’s fiery moon Io produces a similar cloud. Credit: NASA/JPL-Caltech

In 2012, astronomers detected a gas giant transiting in front of WASP-49A, a G-type star located about 635 light-years from Earth. The data obtained by the WASP survey indicated that this exoplanet (WASP-49 b) is a gas giant roughly the same size as Jupiter and 37% as massive. In 2017, WASP-49 b was found to have an extensive cloud of sodium, which was confounding to scientists. Further observations in 2019 using the Hubble Space Telescope detected the presence of other minerals, including magnesium and iron, which appeared to be magnetically bound to the gas giant.

WASP-49 b and its star are predominantly composed of hydrogen and helium, with only trace amounts of sodium – not enough to account for this cloud. In addition, there was no indication of how this sodium cloud was ejected into space. In our Solar System, gas emissions from Jupiter’s volcanic moon Io create a similar phenomenon. In a recent study, an international team led by scientists from NASA’s Jet Propulsion Laboratory found potential evidence of a rocky, volcanic moon orbiting WASP-49 b. While not yet confirmed, the presence of a volcanic exomoon around this gas giant could explain the presence of this sodium cloud.

October 10, 2024October 10, 2024 by Matt Williams

Exoplanet Discovered in a Binary System Could Explain Why Red Dwarfs Form Massive Planets

This artist's concept illustrates a red dwarf star surrounded by exoplanets. Credit: NASA/JPL-Caltech

In recent years, the number of known extrasolar planets (aka. exoplanets) has grown exponentially. To date, 5,799 exoplanets have been confirmed in 4,310 star systems, with thousands more candidates awaiting confirmation. What has been particularly interesting to astronomers is how M-type (red dwarf) stars appear to be very good at forming rocky planets. In particular, astronomers have detected many gas giants and planets that are several times the mass of Earth (Super-Earths) orbiting these low-mass, cooler stars.

Consider TOI-6383A, a cool dwarf star less than half the mass of the Sun that orbits with an even smaller, cooler companion – the red dwarf star TOI-6383B. In a recent study, an international team of astronomers with the Searching for Giant Exoplanets around M-dwarf Stars (GEMS) survey detected a giant planet transiting in front of the primary star, designated TOI-6383Ab. This planet is similar in size and mass to the system’s companion star, which raises questions about the formation of giant planets in red dwarf star systems.

October 7, 2024October 7, 2024 by Matt Williams

The JWST Reveals New Things About How Planetary Systems Form

This artist’s impression of a planet-forming disk surrounding a young star shows a swirling “pancake” of hot gas and dust from which planets form. Credit and ©: National Astronomical Observatory of Japan (NAOJ)

Every second in the Universe, more than 3,000 new stars form as clouds of dust and gas undergo gravitational collapse. Afterward, the remaining dust and gas settle into a swirling disk that feeds the star’s growth and eventually accretes to form planets – otherwise known as a protoplanetary disk. While this model, known as the Nebular Hypothesis, is the most widely accepted theory, the exact processes that give rise to stars and planetary systems are not yet fully understood. Shedding light on these processes is one of the many objectives of the James Webb Space Telescope (JWST).

In a recent study, an international team of astronomers led by University of Arizona researchers and supported by scientists from the Max Planck Institute of Astronomy (MPIA) used the JWST’s advanced infrared optics to examine protoplanetary disks around new stars. These observations provided the most detailed insights into the gas flows that sculpt and shape protoplanetary disks over time. They also confirm what scientists have theorized for a long time and offer clues about what our Solar System looked like roughly 4.6 billion years ago.

October 7, 2024October 7, 2024 by Alan Boyle

Hera Probe Heads Off to See Aftermath of DART’s Asteroid Impact

SpaceX Falcon 9 rocket lifts off with Hera probe — A SpaceX Falcon 9 rocket sends the European Space Agency's Hera spacecraft into space from its Florida launch pad. (Credit: SpaceX)

The European Space Agency’s Hera spacecraft is on its way to do follow-up observations of Dimorphos, two years after an earlier probe knocked the mini-asteroid into a different orbital path around a bigger space rock.

Scientists say the close-up observations that Hera is due to make millions of miles from Earth, starting in 2026, will help them defend our planet from future threats posed by killer asteroids.

October 6, 2024October 6, 2024 by Matt Williams

Primordial Holes Could be Hiding in Planets, Asteroids, and Here on Earth

An artistic take on primordial black holes. Credit: NASA’s Goddard Space Flight Center

Small primordial black holes (PBHs) are one of the hot topics in astronomy and cosmology today. These hypothetical black holes are believed to have formed soon after the Big Bang, resulting from pockets of subatomic matter so dense that they underwent gravitational collapse. At present, PBHs are considered a candidate for dark matter, a possible source of primordial gravitational waves, and a resolution to various problems in physics. However, no definitive PBH candidate has been observed so far, leading to proposals for how we may find these miniature black holes.

Recent research has suggested that main-sequence neutron and dwarf stars might contain small PBHs in their interiors that are slowly consuming their gas supply. In a recent study, a team of physicists extended this idea to include a new avenue for potentially detecting PBHs. Basically, we could search inside objects like planets and asteroids or employ large plates or slabs of metal to detect PBHs for signs of their passage. By detecting the microchannels these bodies would leave, scientists could finally confirm the existence of PBHs and shed light on some of the greatest mysteries in cosmology today.