Saturn is Winning the Moon Contest

Posted on by onespaceman2000
Image (Credit): Saturn’s Death Star-like moon Tethys. (NASA)

So Saturn now has 145 moons due to the discovery of 62 new moons, which is 50 more than the next closest competitor, Jupiter, with 95 moons. You can thank the University of British Columbia (UBC) for the new moon count.

The new discoveries come from a process used by UBC astronomers called ‘shift and stack’:

Shifting a set of sequential images at the rate that the moon is moving across the sky results in enhancement of the moon’s signal when all the data is combined, allowing moons that were too faint to be seen in individual images to become visible in the stacked image. The team used data taken using the Canada-France-Hawaii Telescope (CFHT) on top of Mauna Kea, Hawaii between 2019 and 2021. By shifting and stacking many sequential images taken during three hour spans, they were able to detect moons orbiting Saturn down to about 2.5 kilometres in diameter.

So, as you can read, some of these moons are pretty small. As of today, NASA was still showing 124 moons around Saturn, and another site, theplanets.org, is showing only 62 moons total around the planet. It appear the space agency and others will need to update their pages to show the new mini-moons.

For some reason I doubt the counting is over, just like identified dwarf planets, that seem to range from 5 to 19 at the moment, depending on the source.

The Juice Mission has Started

Posted on by onespaceman2000
Image (Credit): The successful launch of the ESA’s Juice mission from Kourou, French Guiana on April 14, 2023. (ESA/M. Pédoussaut and ESA/CNES/Arianespace/Optique Vidéo du CSG/JM Guillon)

Earlier today, the European Space Agency’s (ESA) Jupiter Icy Moons Explorer (Juice)  mission successfully launched from French Guiana. It is the start of a long trip to the Jovian planet and its moons. The spacecraft will not reach Jupiter until July 2031. You can watch of video of the launch here. ESA has numerous other videos on the mission here.

ESA Director General Josef Aschbacher stated:

ESA, with its international partners, is on its way to Jupiter…Juice’s spectacular launch carries with it the vision and ambition of those who conceived the mission decades ago, the skill and passion of everyone who has built this incredible machine, the drive of our flight operations team, and the curiosity of the global science community. Together, we will keep pushing the boundaries of science and exploration in order to answer humankind’s biggest questions.

It is another great step forward in the exploration of our home solar system as we scan the skies for other more distant systems.

Image (Credit): Juice mission patch. (ESA)

Space Stories: Volcanoes on Venus, Exoplanet Radio Signals, and Bright Baby Jupiter

Posted on by onespaceman2000
Image (Credit): Map of volcanoes located on Venus. (Washington University in St. Louis)

Here are some recent stories of interest.

—Washington University in St. Louis: “Scientists Share ‘Comprehensive’ Map of Volcanoes on Venus — all 85,000 of Them“

Byrne and Hahn’s new study includes detailed analyses of where volcanoes are, where and how they’re clustered, and how their spatial distributions compare with geophysical properties of the planet such as crustal thickness. Taken together, this work provides the most comprehensive understanding of Venus’ volcanic properties — and perhaps of any world’s volcanism so far. That’s because, although we know a great deal about the volcanoes on Earth that are on land, there are still likely a great many yet to be discovered under the oceans. Lacking oceans of its own, Venus’ entire surface can be viewed with Magellan radar imagery.

—CNN: “Repeating Radio Signal Leads Astronomers to an Earth-Size Exoplanet“

Astronomers have detected a repeating radio signal from an exoplanet and the star that it orbits, both located 12 light-years away from Earth. The signal suggests that the Earth-size planet may have a magnetic field and perhaps even an atmosphere…Scientists noticed strong radio waves coming from the star YZ Ceti and the rocky exoplanet that orbits it, called YZ Ceti b, during observations using the Karl G. Jansky Very Large Array of telescopes in New Mexico. The researchers believe the radio signal was created by interactions between the planet’s magnetic field and the star.

—ScienceNews: “Baby Jupiter Glowed so Brightly it Might have Desiccated its Moon“

A young, ultrabright Jupiter may have desiccated its now hellish moon Io. The planet’s bygone brilliance could have also vaporized water on Europa and Ganymede, planetary scientist Carver Bierson reported March 17 at the Lunar and Planetary Science Conference. If true, the findings could help researchers narrow the search for icy exomoons by eliminating unlikely orbits. Jupiter is among the brightest specks in our night sky. But past studies have indicated that during its infancy, Jupiter was far more luminous. “About 10 thousand times more luminous,” said Bierson, of Arizona State University in Tempe.

Space Mission: ESA’s Juice Mission

Posted on by onespaceman2000
Image (Credit): Upper stage of the Ariane 5 rocket that will launch ESA’s Juice mission. (ESA)

On April 13th, the European Space Agency (ESA) will launch its Jupiter Icy Moons Explorer (Juice) mission from French Guiana. The purpose of the mission is to conduct a detailed study of Jupiter as well as three of its moons (and their oceans) – Ganymede, Callisto and Europa. The spacecraft will eventually go into orbit around Ganymede, which will be the first orbit of a moon in our solar system other than Earth’s Moon.

The key milestones for the mission are listed below and shown in greater detail within the graphic as well:

–February 2023: Juice arrives in French Guiana

–April 13, 2023: Launch on Ariane-5 rocket

–July 2031: Arrival at Jupiter

-July 2031 – November 2034: 35 icy moon flybys

–December 2034: Arrival at Ganymede

Image (Credit): Juice mission milestones. (ESA JUICE Launch Kit)

In addition to ESA/European scientific instruments and equipment, the spacecraft will also carry items from NASA, the Japan Aerospace Exploration Agency, and the Israel Space Agency.

The delayed arrival at Jupiter relates to the need for multiple flybys cover this great distance. In The Financial Times, Justin Byrne, head of science for lead contractor Airbus, stated, “Ariane-5 is a very powerful rocket but it can only give us about half the energy we need to get to Jupiter…We get the rest by doing planetary fly-bys, each one giving us a gravitational assist through a slingshot manoeuvre.”

The ESA put together a useful Launch Kit that answers any question you may have about the Juice mission, as well as related missions.

Space Stories: Jovian Moons, Charon’s Canyons, and a New Space Telescope

Posted on by onespaceman2000
Image (Credit): Jupiter as seen by the NASA/ESA Hubble Space Telescope. (NASA, ESA, A. Simon (Goddard Space Flight Center), and M.H. Wong (University of California, Berkeley)

Here are some recent stories of interest.

—Live Science: “Jupiter Officially has the Most Moons in the Solar System, Discovery of 12 New Satellites Confirms“

Jupiter was already the king of the solar system, and new discoveries give the massive planet another way to reign supreme: It now has the most moons. Twelve new moons discovered orbiting Jupiter have been confirmed, bumping the count from 80 to 92, and knocking Saturn — which has 83 moons — down a peg. 

—Phys.org: “Models Explain Canyons on Pluto’s Large Moon Charon“

In 2015, when NASA’s New Horizons spacecraft encountered the Pluto-Charon system, the Southwest Research Institute-led science team discovered interesting, geologically active objects instead of the inert icy orbs previously envisioned. An SwRI scientist has revisited the data to explore the source of cryovolcanic flows and an obvious belt of fractures on Pluto’s large moon Charon. These new models suggest that when the moon’s internal ocean froze, it may have formed the deep, elongated depressions along its girth but was less likely to lead to cryovolcanoes erupting with ice, water and other materials in its northern hemisphere.

—Big Think: “NASA’s Habitable Worlds Observatory to Finally Answer the Epic Question: “Are we Alone?”“

…perhaps the biggest question of all — that of “Are we alone in the Universe?” — remains a mystery. While the current generation of ground-based and space-based telescopes can take us far into the Universe, this is a question that’s currently beyond our reach. To get there, we’ll need to directly image Earth-like exoplanets: planets with sizes and temperatures similar to Earth, but that orbit Sun-like stars, not the more common red dwarf stars like Proxima Centauri or TRAPPIST-1. Those capabilities are precisely what NASA is aiming for with its newly announced flagship mission: the Habitable Worlds Observatory. It’s an ambitious project but one that’s well worth it. After all, finding out we’re not alone in the Universe would quite possibly be the biggest revolution in all of science history.