Astro Blog

By  Jamie M. Jasinsk  et al, Nature Astronomy. Summary: A human spacecraft has only gotten close to Uranus once—in 1986, when Voyager 2 drifted past the distant planet. That flyby indicated that   Uranus was weird in several ways , which astronomers have spent decades trying to explain. Now, a new analysis in   Nature Astronomy   suggests the probe   just happened to arrive there on an off day . Voyager 2’s data indicated that Uranus had an “unusually oblique and off-centered magnetic field” with inexplicably intense electron radiation belts and a severely plasma-depleted magnetosphere,” the team behind the new work writes. But by mining old data from the mission, the scientists found evidence for a super strong solar wind that likely squished the magnetosphere just prior to the probe’s readings. This would have pushed any plasma too close to the planet to detect, and filled the radiation belts with high-energy particles. https://www.nature.com/articles/s41...

https://www.nasa.gov/feature/jpl/nasa-mission-update-voyager-2-communications-pause By Calla Cofield, Jet Propulsion Laboratory.  Excerpt: ... Voyager 2  is located more than 12.3 billion miles (19.9 billion kilometers) from Earth...A series of planned commands sent to NASA’s Voyager 2 spacecraft July 21 inadvertently caused the antenna to point 2 degrees away from Earth. As a result, Voyager 2 [was] unable to receive commands or transmit data back to Earth. The agency’s Deep Space Network facility in Canberra, Australia, sent the equivalent of an interstellar “shout” more than 12.3 billion miles (19.9 billion kilometers) to Voyager 2, instructing the spacecraft to reorient itself and turn its antenna back to Earth. With a one-way light time of 18.5 hours for the command to reach Voyager, it took 37 hours for mission controllers to learn whether the command worked. At 12:29 a.m. EDT on Aug. 4, the spacecraft began returning science and telemetry data, indicating it is ope...

https://www.nytimes.com/2019/11/04/science/voyager-2-interstellar-solar-wind.html Source:   By Kenneth Chang. The New York Times. Excerpt: The Voyager 2 spacecraft burst out of the bubble of gases expanding from the sun and into the wild of the Milky Way a year ago. It was the second spacecraft to cross that boundary and directly observe the interstellar medium. Its faster-moving twin, Voyager 1, made the crossing six years earlier, in August 2012. Launched 42 years ago, when Jimmy Carter was president, the twin spacecraft have persisted far longer than envisioned, as has their ability to send scientific findings home to Earth. In a series of papers published on Monday in Nature Astronomy [https://www.nature.com/articles/s41550-019-0928-3], scientists report what Voyager 2 observed at the boundary of the solar wind’s bubble and beyond....

Source:   By Robert Sanders, Media relations, UC Berkeley News Excerpt: Taking advantage of a rare orbital alignment between two of Jupiter’s moons, Io and Europa, researchers have obtained an exceptionally detailed map of the largest lava lake on Io, the most volcanically active body in the solar system. ...Overturning lava is a popular explanation for the periodic brightening and dimming of the hot spot, called Loki Patera after the Norse god. (A patera is a bowl-shaped volcanic crater.) The most active volcanic site on Io, which itself is the most volcanically active body in the solar system, Loki Patera is about 200 kilometers (127 miles) across. The hot region of the patera has a surface area of 21,500 square kilometers, larger than Lake Ontario. Earthbound astronomers first noticed Io’s changing brightness in the 1970s, but only when the Voyager 1 and 2 spacecraft flew by in 1979 did it become clear that this was because of volcanic eruptions on the surface. Despite highl...

Source:    NASA RELEASE: 11-402 Excerpt:  NASA's Voyager 1 spacecraft has entered a new region between our solar system and interstellar space.  ...Although Voyager 1 is about 11 billion miles (18 billion kilometers) from the sun, it is not yet in interstellar space.  ...Scientists previously reported the outward speed of the solar wind had diminished to zero in April 2010, marking the start of the new region.  …"We've been using the flow of energetic charged particles at Voyager 1 as a kind of wind sock to estimate the solar wind velocity," said Rob Decker,... "We've found that the wind speeds are low in this region and gust erratically. For the first time, the wind even blows back at us. We are evidently traveling in completely new territory. ...For more information about the Voyager spacecraft, visit: http://www.nasa.gov/voyager  www.nasa.gov/home/hqnews/2011/dec/HQ_11-402_AGU_Voyager.html

Source:   Nancy Atkinson, Universe Today Saturn’s rings have several gaps, most of which are caused by small moons shepherding ring debris into breaks in the rocky rings. But one gap may be caused by gravitational perturbations from Saturn’s largest moon, Titan, sending tsunami-like waves up to 3 kilometers (2 miles) high in the C ring. … “The whole pattern rotates around at the same rate as the satellite Titan orbits Saturn, once every 16 days,” said Nicholson said.... www.universetoday.com/74929/titan-ic-tsunami-causing-crack-in-saturn%E2%80%99s-c-ring/