Matt Williams, Author at Universe Today

June 28, 2024June 28, 2024 by Matt Williams

These Three Neutron Stars Shouldn't Be So Cold

Artist's impression of a neutron star, with white/blue filaments are streaming out from its polar regions, representing magnetic field lines. Credit: ESA

Neutron stars are among the densest objects in the Universe, second only to black holes. Like black holes, neutron stars are what remains after a star reaches the end of its life cycle and undergoes gravitational collapse. This produces a massive explosion (a supernova), in which a star sheds its outer layers and leaves behind a super-compressed stellar remnant. In fact, scientists speculate that matter at the center of the star is compressed to the point that even atoms collapse and electrons merge with protons to create neutrons.

Traditionally, scientists have relied on the “Equation of State” – a theoretical model that describes the state of matter under a given set of physical conditions – to understand what physical processes can occur inside a neutron star. But when a team led by scientists from the Spanish National Research Council (CSIC) examined three exceptionally young neutron stars, they noticed they were 10-100 times colder than other neutron stars of the same age. For this, the researchers concluded that these three stars are inconsistent with most of the proposed equations of state.

June 28, 2024June 28, 2024 by Matt Williams

Making Rocket Fuel Out of Lunar Regolith

An illustration of a Moon base that could be built using 3D printing and ISRU, In-Situ Resource Utilization. Credit: RegoLight, visualisation: Liquifer Systems Group, 2018

In the coming years, NASA and other space agencies plan to extend the reach of human exploration. This will include creating infrastructure on the Moon that will allow for crewed missions on a regular basis. This infrastructure will allow NASA and its international partners to make the next great leap by sending crewed missions to Mars (by 2039 at the earliest). Having missions operate this far from Earth for extended periods means that opportunities for resupply will be few and far between. As a result, crews will need to rely on In-Situ Resource Utilization (ISRU), where local resources are leveraged to provide for basic needs.

In addition to air, water, and building materials, the ability to create propellant from local resources is essential. According to current mission architectures, this would consist of harvesting water ice in the polar regions and breaking it down to create liquid oxygen (LOX) and liquid hydrogen (LH₂). However, according to a new study led by engineers from McGill University, rocket propellant could be fashioned from lunar regolith as well. Their findings could present new opportunities for future missions to the Moon, which would no longer be restricted to the polar regions.

June 24, 2024June 24, 2024 by Matt Williams

Simulating the Last Moments Before Neutron Stars Merge

Volume rendering of density in a simulation of a binary neutron star merger. New research shows that neutrinos created in the hot interface between the merging stars can be briefly trapped and remain out of equilibrium with the cold cores of the merging stars for 2 to 3 milliseconds. Credit: David Radice/Penn State

When stars reach the end of their life cycle, they shed their outer layers in a supernova. What is left behind is a neutron star, a stellar remnant that is incredibly dense despite being relatively small and cold. When this happens in binary systems, the resulting neutron stars will eventually spiral inward and collide. When they finally merge, the process triggers the release of gravitational waves and can lead to the formation of a black hole. But what happens as the neutron stars begin merging, right down to the quantum level, is something scientists are eager to learn more about.

When the stars begin to merge, very high temperatures are generated, creating “hot neutrinos” that remain out of equilibrium with the cold cores of the merging stars. Ordinarily, these tiny, massless particles only interact with normal matter via weak nuclear forces and possibly gravity. However, according to new simulations led by Penn State University (PSU) physicists, these neutrinos can weakly interact with normal matter during this time. These findings could lead to new insights into these powerful events.

June 20, 2024June 20, 2024 by Matt Williams

Matched Twin Stars are Firing Their Jets Into Space Together

This artist’s concept shows two young stars nearing the end of their formation. Encircling the stars are disks of leftover gas and dust from which planets may form. Jets of gas shoot away from the stars’ north and south poles. Credit: NASA

Since it began operating in 2022, the James Webb Space Telescope (JWST) has revealed some surprising things about the Universe. The latest came when a team of researchers used Webb‘s Mid-Infrared Instrument (MIRI) to observe Rho Ophiuchi, the closest star-forming nebula to Earth, about 400 light-years away. While at least five telescopes have studied the region since the 1970s, Webb’s unprecedented resolution and specialized instruments revealed what was happening at the heart of this nebula.

For starters, while observing what was thought to be a single star (WL 20S), the team realized they were observing a pair of young stars that formed 2 to 4 million years ago. The MIRI data also revealed that the twin stars have matching jets of hot gas (aka stellar jets) emanating from their north and south poles into space. The discovery was presented at the 244th meeting of the American Astronomical Society (224 AAS) on June 12th. Thanks to additional observations made by the Atacama Large Millimeter/submillimeter Array (ALMA), the team was surprised to notice large clouds of dust and gas encircling both stars.

June 15, 2024June 15, 2024 by Matt Williams

New Simulation Explains how Supermassive Black Holes Grew so Quickly

Supermassive Black Hole Survey. Credit: ESA/XMM-Newton/PSU/F. Zou et al./N.Trehnl/The TNG Collaboration

One of the main scientific objectives of next-generation observatories (like the James Webb Space Telescope) has been to observe the first galaxies in the Universe – those that existed at Cosmic Dawn. This period is when the first stars, galaxies, and black holes in our Universe formed, roughly 50 million to 1 billion years after the Big Bang. By examining how these galaxies formed and evolved during the earliest cosmological periods, astronomers will have a complete picture of how the Universe has changed with time.

As addressed in previous articles, the results of Webb‘s most distant observations have turned up a few surprises. In addition to revealing that galaxies formed rapidly in the early Universe, astronomers also noticed these galaxies had particularly massive supermassive black holes (SMBH) at their centers. This was particularly confounding since, according to conventional models, these galaxies and black holes didn’t have enough time to form. In a recent study, a team led by Penn State astronomers has developed a model that could explain how SMBHs grew so quickly in the early Universe.

June 15, 2024June 15, 2024 by Matt Williams

Don't Get Your Hopes Up for Finding Liquid Water on Mars

In the coming decades, NASA and China intend to send the first crewed missions to Mars. Given the distance involved and the time it takes to make a single transit (six to nine months), opportunities for resupply missions will be few and far between. As a result, astronauts and taikonauts will be forced to rely on local resources to meet their basic needs – a process known as in-situ resource utilization (ISRU). For this reason, NASA and other space agencies have spent decades scouting for accessible sources of liquid water.

Finding this water is essential for future missions and scientific efforts to learn more about Mars’s past, when the planet was covered by oceans, rivers, and lakes that may have supported life. In 2018, using ground-penetrating radar, the ESA’s Mars Express orbiter detected bright radar reflections beneath the southern polar ice cap that were interpreted as a lake. However, a team of Cornell researchers recently conducted a series of simulations that suggest there may be another reason for these bright patches that do not include the presence of water.

June 13, 2024June 13, 2024 by Matt Williams

NASA is Considering Other Ways of Getting its Mars Samples Home

Artist's impression of the NASA-ESA Mars Sample Return mission. Credit: NASA

In 2021, NASA’s Perseverance rover landed in the Jezero Crater on Mars. For the next three years, this astrobiology mission collected soil and rock samples from the crater floor for eventual return to Earth. The analysis of these samples is expected to reveal much about Mars’ past and how it transitioned from being a warmer, wetter place to the frigid and desiccated place we know today. Unfortunately, budget cuts have placed the future of the proposed NASA-ESA Mars Sample Return (MSR) mission in doubt.

As a result, NASA recently announced that it was seeking proposals for more cost-effective and rapid methods of bringing the samples home. This will consist of three studies by NASA and the Johns Hopkins University Applied Physics Laboratory (JHUAPL). In addition, NASA has selected seven commercial partners for firm-fixed-price contracts for up to $1.5 million to conduct their own 90-day studies. Once complete, NASA will consider which proposals to integrate into the MSR mission architecture.

June 9, 2024June 9, 2024 by Matt Williams

Instead of Losing its Atmosphere, an Exoplanet Puffed Up and Held Onto it

Artist's impression of the "hot Neptune" Phoenix orbiting its red giant star. Credit: Credit: Roberto Molar Candanosa/JHU

To date, astronomers have confirmed the existence of 5638 extrasolar planets in 4,199 star systems. In the process, scientists have found many worlds that have defied expectations. This is certainly the case regarding “hot Neptunes,” planets that are similar to the “ice giants” of the outer Solar System but orbit much closer to their stars. But when a Johns Hopkins University-led team of astronomers discovered TIC365102760 b (aka. Pheonix), they observed something entirely unexpected: a Neptune-sized planet that retained its atmosphere by puffing up.

June 6, 2024June 6, 2024 by Matt Williams

Astronauts are Practicing Lunar Operations in New Space Suits

Astronauts were fully suited while conducting mission-like maneuvers in the full-scale build of the Starship human landing system’s airlock which will be located inside Starship under the crew cabin. Credit: SpaceX

Through the Artemis Program, NASA will send astronauts to the lunar surface for the first time since 1972. While the challenges remain the same, the equipment has evolved, including the rocket, spacecraft, human landing system (HLS), and space suits. In preparation for Artemis III (planned for September 2026), NASA recently conducted a test where astronauts donned the new space suits developed by Axiom Space and practiced interacting with the hardware that will take them to the Moon.

June 5, 2024June 6, 2024 by Matt Williams

Starliner Finally Launches, Carrying Two Astronauts Into Orbit

Boeing's CTS-100 Starliner taking off from Cape Canaveral, Florida, on June 5th, 2024. Credit: NASA

After many delays and two scrubbed launch attempts, Boeing’s CST-100 Starliner successfully launched earlier today! The Crewed Flight Test (CFT) took off from Space Launch Complex-41 at Cape Canaveral Space Force Station, Florida, at 10:52 a.m. EDT (07:52 PDT) atop a ULA Atlas V rocket. For this mission, the capsule is carrying two NASA astronauts: Barry “Butch” Wilmore (commander) and Sunita “Suni” Williams (pilot). They are expected to reach the International Space Station (ISS) at 12:15 p.m. EDT (09:15 a.m. PDT) on Thursday, June 6th.