Mark Megahan
Thanks to the heavy duty new high-tech equipment aboard the James Webb Space Telescope, we can view the elusive rings of Neptune with rarely observed precision. The infrared instruments can “highlight features not seen in such detail since the Voyager 2 probe flew past the planet in 1989.”
The rings of Neptune
The band of rings around Neptune isn’t as bold or extensively formed as the ones surrounding Saturn but they’re made up of the same dust and rocks.
Webb also picked up some “different cloud structures,” which intrigue scientists because they can “tell them something novel about the workings of Neptune’s atmosphere.”
Neptune has 14 moons and 7 of them were imaged by Webb. The one with the biggest visual impact is Triton, which “appears star-like in the Webb imagery.”
The reason for that is because the frozen gas giant “is darkened in the telescope’s view by methane absorption at infrared wavelengths.” Meanwhile, Triton “reflects an average of 70% of the sunlight that strikes its icy surface.” That makes it exceptionally bright.
Modern technology has its pluses and minuses, as Professor Leigh Fletcher of Leicester University observes. He’s at the Europlanet Science Congress in Granada, Spain, and everyone there is trying to analyze Neptune images that look like a postage stamp.
Everyone, he says, is “trying to interpret this on our phones, but it’s incredible to see those rings, and we’re accessing wavelengths that no-one has seen before. Its great to see how excited everyone is!”
Deep circulation patterns
They’re really amazed at the Webb images because “the longer wavelengths are brand new and could give us a window on to the deep circulation patterns, with a bright equatorial band that looks a bit like the bright bands of Jupiter and Saturn.”
Even far away from the sun, the planet’s “powerful storms are as active as ever, and the whole Neptune family is represented here, with those ring moons and Triton.”
Now that Pluto has been demoted, Neptune is the outermost planet in our Solar System. It lies 2.8 billion miles from the sun and takes 164.8 years to complete one revolution. Just like the other gas giants, Neptune’s is mostly hydrogen and helium.
Along with those are “a very strong presence of ices, of water, ammonia and methane.” That makes it potentially useful for a refueling stop some day.
The planet Neptune seems small because it is so far away but it’s actually four times as wide as Earth. Recently the mid-range infrared equipment on the James Webb Space Telescope developed some problems.
The grating wheel is experiencing some unknown “friction” which means that parts of the equipment are currently out of service. That’s on top of the ding in one mirror which happened before it even went online. Unlike with Hubble, repair and service missions aren’t an option.
