Behold: four of Saturn’s 82 true moons. Four you say? That’s right, four. To wit:
First — and farthest in the background — is Titan, the largest moon of Saturn and one of the larger moons in the Solar System. The dark feature across the top of this perpetually cloudy world is the north polar hood. The next most obvious moon is bright Dione, visible in the foreground, complete with craters and long ice cliffs. Jutting in from the left are several of Saturn’s expansive rings, including Saturn’s A ring featuring the dark Encke Gap. On the far right, just outside the rings, is Pandora, a moon only 80-kilometres across that helps shepherd Saturn’s F ring. The fourth moon? If you look closely inside Saturn’s rings, in the Encke Gap, you will find a speck that is actually Pan. Although one of Saturn’s smallest moons at 35-kilometres across, Pan is massive enough to help keep the Encke gap relatively free of ring particles. After more than a decade of exploration and discovery, the Cassini spacecraft ran low on fuel in 2017 and was directed to enter Saturn’s atmosphere, where it surely melted.
(Image: Cassini Imaging Team, ISS, JPL, ESA, NASA)
What are these streaks in the sky? They’re more orbiting agents of Elon Musk is what they are. To wit:
SpaceX launched 60 Starlink communication satellites in May and 60 more in November. These satellites and thousands more are planned by communications companies in the next few years that may make streaks like these relatively common. Concern has been voiced by many in the astronomical community about how reflections from these satellites may affect future observations into space. In the pictured composite of 33 exposures, parallel streaks from Starlink satellites are visible over southern Brazil. Sunflowers dot the foreground, while a bright meteor was caught by chance on the upper right. Satellite reflections are not new — the constellation of 66 first-generation Iridium satellites launched starting 20 years ago produced some flares so bright that they could be seen during the day. Most of these old Iridium satellites, however, have been de-orbited over the past few years.
(Image: Egon Filter)
The graveyard of outer space – crowded with some 17,000 spent rocket stages, dead or dying satellites and countless crumbs of human-made orbital flotsam – is building toward critical mass, colliding, creating more debris. According to experts at the John Hopkins Space Department, it’s now inevitable that every satellite in orbit will be ‘percussively decommissioned’. According to Gen. William Shelton, commander of USAF Space Command:
“The traffic is increasing. We’ve now got over 50 nations that are participants in the space environment,” Shelton said last month during the Space Foundation’s 27th National Space Symposium. Given existing space situational awareness capabilities, over 20,000 objects are now tracked.
“We catalog those routinely and keep track of them. That number is projected to triple by 2030, and much of that is improved sensors, but some of that is increased traffic,” Shelton said. “Then if you think about it, there are probably 10 times more objects in space than we’re able to track with our sensor capability today. Those objects are untrackable … yet they are lethal to our space systems — to military space systems, civil space systems, commercial — no one’s immune from the threats that are in orbit today, just due to the traffic in space.”
Ugly Truth of Space Junk: Orbital Debris Problem to Triple by 2030 (Space.com)