Universe Today

February 1, 2023January 29, 2023 by Paul M. Sutter

Astronomers Come Closer to Understanding How Mercury Formed

Artist's concept of the MESSENGER spacecraft on approach to Mercury. Credit: NASA/JPL

Simulations of the formation of the solar system have been largely successful. They are able to replicate the positions of all the major planets along with their orbital parameters. But current simulations have an extreme amount of difficulty getting the masses of the four terrestrial planets right, especially Mercury. A new study suggests that we need to pay more attention to the giant planets in order to understand the evolution of the smaller ones.

February 1, 2023February 1, 2023 by Matt Williams

Rolls-Royce Reveals a Nuclear Reactor That Could Provide Power on the Moon

For space agencies and the commercial space industry, the priorities of the next two decades are clear. First, astronauts will be sent to the Moon for the first time since the Apollo Era, followed by the creation of permanent infrastructure that will allow them to say there for extended periods. Then, the first crewed missions will be sent to Mars, with follow-up missions every 26 months, culminating in the creation of surface habitats (and maybe a permanent base). To meet these objectives, space agencies are investigating next-generation propulsion, power, and life support systems.

This includes solar-electric propulsion (SEP), where solar energy is used to power extremely fuel-efficient Hall-Effect thrusters. Similarly, they are looking into nuclear thermal propulsion (NTP) and compact nuclear reactors, allowing for shorter transit times and providing a steady power supply for Lunar and Martian habitats. Beyond NASA, the UK Space Agency (UKSA) has partnered with Rolls-Royce to develop nuclear systems for space exploration. In a recent tweet, the international auto and aerospace giant provided a teaser of what their “micro-reactor” will look like.

February 1, 2023February 1, 2023 by Evan Gough

Astronomers Detect a Second Planet Orbiting Two Stars

Artist's impression of Kepler-16b, the first planet known to definitively orbit two stars - what's called a circumbinary planet. The planet, which can be seen in the foreground, was discovered by NASA's Kepler mission. Credit: NASA/JPL-Caltech/T. Pyle

Planets orbiting binary stars are in a tough situation. They have to contend with the gravitational pull of two separate stars. Planetary formation around a single star like our Sun is relatively straightforward compared to what circumbinary planets go through. Until recently, astronomers weren’t sure they existed.

January 31, 2023January 31, 2023 by Evan Gough

Don’t Bother Trying to Destroy Rubble Pile Asteroids

Detailed view of the rubble-pile asteroid 25143 Itokawa visited by the Japanese spacecraft Hayabusa in 2005. Credit: JAXA

The asteroids in our Solar System are survivors. They’ve withstood billions of years of collisions. The surviving asteroids are divided into two groups: monolithic asteroids, which are intact chunks of planetesimals, and rubble piles, which are made of up fragments of shattered primordial asteroids.

It turns out there are far more rubble pile asteroids than we thought, and that raises the difficulty of protecting Earth from asteroid strikes.

January 31, 2023January 31, 2023 by Nancy Atkinson

Watch This 12-Year Timelapse of Exoplanets Orbiting Their Star

Four faint exoplanets orbit star HR8799, which is represented by a star-shaped icon in the center. (The star itself was removed from the video because its glare is so intense that it blocks out the surrounding planets.) Credit: Jason Wang/Northwestern University.

Back in 2008, astronomers made a big announcement: for the first time, they had taken pictures of a multi-planet solar system, much like ours, orbiting another star. At the time, the star system, named HR8799 was known to have three planets, but follow-up observations a year later revealed a fourth world.

Astronomers have continued to watch this intriguing star system, and now, using observations from the last 12 years, astrophysicist Jason Wang has put together a time lapse video showing the orbital motions of the four planets.

January 31, 2023January 31, 2023 by Laurence Tognetti

Freezing Ocean Might Not Be Responsible for Cryovolcanic Flows on Pluto’s Moon, Charon

Color-enhanced image of Pluto's largest moon, Charon, taken by NASA's New Horizons spacecraft on July 14, 2015. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)

In a recent study scheduled to be published in the journal Icarus in March 2023, a team of researchers led by the Southwest Research Institute (SwRI) modeled a potential correlation between an ancient freezing ocean with cryovolcanic flows and surface canyons on Pluto’s largest moon, Charon. Their hypothesis was that when Charon’s interior ocean froze long ago, the significant stress put on the icy outer shell from the addition of more ice to the bottom of the existing shell could have been responsible for the cryovolcanic flows on the surface.

January 31, 2023January 31, 2023 by Laurence Tognetti

South Korea’s Danuri Mission Sends Home Pictures of the Earth and Moon

Credit: Korea Aerospace Research Institute (KARI)

The Korea Aerospace Research Institute (KARI) both ended 2022 and started 2023 on a very high note as its first-ever lunar orbiter, Danuri, sent back black-and-white images of the Earth with the Moon’s surface in the foreground that were photographed between December 24 and January 1, KARI announced in a January 3^rd statement. Both the images and videos were taken less than 120 kilometers (75 miles) above the Moon’s surface, and will be “used to select potential sites for a Moon landing in 2032,” KARI added in the statement.

January 31, 2023January 31, 2023 by Carolyn Collins Petersen

Soon We’ll Detect Extreme Objects Producing Gravitational Waves Continuously

An artist's concept of a binary pair where a smaller star is feeding material to a neutron star. Perturbations in the neutron star may be sending a constant wash of gravitational waves through space. Courtesy Gabriel Pérez Díaz, SMM (IAC)

The cosmic zoo contains objects so bizarre and extreme that they generate gravitational waves. Scorpius X-1 is part of that strange collection. It’s actually a binary pair: a neutron star orbiting with a low-mass stellar companion called V818 Scorpii. The pair provides a prime target for scientists hunting for so-called “continuous” gravitational waves. Those waves should exist, although none have been detected—yet.

January 30, 2023February 3, 2023 by Laurence Tognetti

The Outer Solar System Supplied a Surprising Amount of Earth’s Water

Currently exploring the Kuiper Belt, New Horizons is just one of five spacecraft to reach beyond 50 astronomical units, on its way out of the solar system and, eventually, into interstellar space. (Credit: NASA/Johns Hopkins APL/Southwest Research Institute)

In a recent study published in Science, a team of researchers at Imperial College London examined 18 meteorites containing the volatile element zinc to help determine their origin, as it has been long hypothesized that Earth’s volatiles materials, including water, were derived from asteroids closer to our home planet. However, their results potentially indicate a much different origin story.

January 30, 2023January 31, 2023 by Laurence Tognetti

Scientists Examine Geological Processes of Monad Regio on Neptune’s Largest Moon, Triton

Global color mosaic of Neptune's largest moon, Triton, taken by NASA's Voyager 2 in 1989. (Credit: NASA/JPL-Caltech/USGS)

In a recent study submitted to the journal Icarus, a team of researchers at the International Research School of Planetary Science (IRSPS) located at the D’Annunzio University of Chieti-Pescara in Italy conducted a geological analysis of a region on Neptune’s largest moon, Triton, known as Monad Regio to ascertain the geological processes responsible for shaping its surface during its history, and possibly today. These include what are known as endogenic and exogenic processes, which constitute geologic processes occurring internally (endo-) and externally (exo-) on a celestial body. So, what new insights into planetary geologic processes can we learn from this examination of Monad Regio?