Former President Donald Trump’s campaign and his eldest son, Don Jr., say they are thrilled with Sen. J.D. Vance’s performance on the campaign trail in comparison to Minnesota Gov. Tim Walz, in exclusive…

[unable to retrieve full-text content]For more than a century, dams have blocked fish migration on California’s second-largest river. VOA’s Matt Dibble takes us to the removal of the last of four…

Readers, Instead of sucking up to the political and corporate powers that dominate America, The Daily Caller is fighting for you — our readers. We humbly ask you to consider joining us in this fight.…

Jupiter’s moon, Ganymede, is a fascinating celestial body. Measuring 2,634 km (1,636 mi) in diameter, it is also the largest satellite in the Solar System and even larger than Mercury, which measures 2,440 km (1,516 mi) in diameter. Like Europa, it has an interior ocean and is one of the few bodies in the Solar System (other than the gas giants) with an intrinsic magnetic field. The presence of this field also means Ganymede experiences aurorae circling the regions around its northern and southern poles due to interaction with Jupiter’s magnetic field. In addition, based on its surface craters, scientists believe that Ganymede experienced a powerful impact with an asteroid about 4 billion years ago. This asteroid was about 20 times larger than the Chicxulub asteroid that caused the extinction of the dinosaurs, or the Cretaceous–Paleogene extinction event (ca. 66 million years ago). According to a recent study by Naoyuki Hirata of Kobe University, this impact occurred almost precisely on the meridian farthest away from Jupiter. This caused a reorientation of Ganymede’s rotational axis and allowed Hirata to determine exactly what type of impact took place. Naoyuki Hirata is an assistant professor with the Department of Planetology at Kobe University’s Graduate School of Science. His paper, “Giant impact on early Ganymede and its subsequent reorientation,” recently appeared in Science Reports. Since the Pioneer 10 and 11 and the Voyager 1 and 2 probes flew through the Jupiter system in the 1970s, scientists have known that large parts of Ganymede’s surface are covered by furrows that form concentric circles around a single spot. This led researchers in the 1980s to conclude that these were the result of a major impact event. On large parts of its surface, Ganymede is covered by furrows (right) that form concentric circles around one specific spot (left, red cross). © HIRATA Naoyuki The exact nature of this impact and its effects on Ganymede has been the subject of debate ever since. As Hirata said in a Kobe University press release: “The Jupiter moons Io, Europa, Ganymede, and Callisto all have interesting individual characteristics, but the one that caught my attention was these furrows on Ganymede. We know that this feature was created by an asteroid impact about 4 billion years ago, but we were unsure how big this impact was and what effect it had on the moon.” Using data obtained by the New Horizons mission of Pluto, Hirata drew on similarities with an impact event on Pluto that caused a shift in the (dwarf) planet’s rotational axis. As a specialist who simulates impact events on moons and asteroids, Hirata was able to calculate what kind of impact would have caused Ganymede’s orientation to shift. According to his estimates, the asteroid had a diameter of around 300 km (~186.5 mi) that created a crater measuring between 1,400 and 1,600 km (870 and 995 mi) in diameter before the debris resettled on the surface. Evidence of this impact is visible today in the center of the furrow system on the anti-Jovian side of Ganymede (the hemisphere facing away from Jupiter) and currently measures roughly 1,000 km (662 mi) in diameter. Looking ahead, Hirata hopes to learn how this impact could have affected the moon’s evolution, particularly where its internal ocean is involved: “I want to understand the origin and evolution of Ganymede and other Jupiter moons. The giant impact must have had a significant impact on the early evolution of Ganymede, but the thermal and structural effects of the impact on the interior of Ganymede have not yet been investigated at all. I believe that further research applying the internal evolution of ice moons could be carried out next.” Distribution of furrows and the location of the center of the furrow system shown in the hemisphere that always faces away from Jupiter (top) and the cylindrical projection map of Ganymede (bottom). © HIRATA Naoyuki. The ESA’s JUpiter ICy moons Explorer (JUICE) mission is currently en route to Jupiter and will establish orbit around Ganymede by 2034. The observations it makes over the next six months will help shed light on these and other questions regarding Ganymede and its sibling satellites, Europa and Callisto – not the least of which is whether or not these “Ocean Worlds” can support life. Further Reading: Kobe University, Scientific Reports The post Ouch! A Monster Asteroid Crashed Into Ganymede 4 Billion Years Ago, Rolling it Over appeared first on Universe Today.

The European Space Agency (ESA) launched its final Vega rocket this week, lofting a Sentinel-2C Earth observation satellite into orbit. This wraps up 12 years of service and 20 successful flights for the venerable Vega. The rocket launched several well-known missions, including LISA Pathfinder (2015), the Earth-observing satellites Proba-V (2013), and Aeolus (2018). ESA will now launch these types of payloads on the new Vega-C rocket, capable of launching heavier payloads at a lower price. Vega’s final launch was on September 5, 2024 from Europe’s Spaceport in French Guiana, and ESA said that it was fitting the rocket boosted to orbit one of the Sentinel satellites, as Vega had previously launched Sentinel-2A in 2015 and Sentinel-2B in 2017. Vega was a smaller but powerful rocket launcher designed to loft smaller science and Earth observation satellites, specializing in launching of satellites into polar orbit. At 30 meters (98 ft) tall the rocket weighs 137 tons on the launch pad. Vega consisted of three solid-propellant powered stages with the a liquid-propellant fourth stage.  before the fourth liquid-propellant stage took over to bring satellites to their required orbit. Vega could reach space in just six minutes. On 13 February 2012, the first Vega lifted off on its maiden flight from Europe’s South American Spaceport in French Guiana and deployed 9 science satellites. Credits: ESA – S. Corvaja Vega’s first launch took place in February 2012, conducting a perfectly executed qualification flight to deploy 9 science cubesats into Earth orbit. On Vega’s second flight in 2013, a secondary payload adapter called Vespa was added. This provided different options for payload ride-sharing where multiple satellites could be launched on one rocket. This flight brought three satellites to orbit — Earth observation satellites, ESA’s Proba-V, Vietnam’s VNREDSat-1A and Estonia’s first satellite, the ESTCube-1 technology demonstrator. All three were released into different orbits and the complex mission required five upper-stage boosts, with the flight lasting about twice as long as its first launch. Countdown and launch of Vega’s final flight. The most satellites Vega ever launched to orbit was in 2020 when a variant of Vespa was used — called the Small Spacecraft Mission Service — and brought over 50 satellites at once to orbit. 2015 was Vega’s’ busiest year, launching three ESA missions including a reentry demonstrator called IXV that prove the technology to launch a vehicle to space and return it safely to Earth. According to ESA, in less than two hours Vega accelerated IXV to speeds of 27,000 km/h (16,777 mph) at a height of 412 km (250 miles) before the reentry vehicle splashed down in the Atlantic Ocean. But now ESA is building on Vega’s heritage, and the era of Vega-C has already begun. This new rocket completed its inaugural flight in July of 2022, putting the main payload LARES-2 – a scientific mission of the Italian Space Agency ASI – into orbit as well as six research CubeSats from France, Italy and Slovenia. ESA said Vega-C will provide better performance and greater payload capability as it has two new solid propulsion stages, an uprated fourth stage, a newly designed fairing, and new ground infrastructure. Lift-off of a Vega-C rocket, with the Lares-2 mission plus rideshares. Credit: ESA The post The Final Vega Rocket Blasts Off appeared first on Universe Today.

You can't unsee this.