A pair of stars just over 5,000 lightyears away called Wolf–Rayet 140 orbit each other such that, every eight years, they come close enough that their stellar winds meet, compressing the gas and dust they naturally release into shells.
When we look at the system, those shells seem to form rings; in the image, there's at least 17 of them—corresponding to rings formed going back at least to 1886 (in terms of when the light reached us; add 5,600 ± 300 years to that).
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Friends, a few weeks ago I told you about something called Phantom—the Venus balloon mission concept I've been leading since January.
In July, we successfully flight-tested a subscale prototype of our balloon in the Nevada desert.
Now we've a video of those tests.
Take a look.
This video documents just a tiny bit of the *enormous* amount of work folks have put into developing these balloons—much of that work predating my joining the mission concept team.
Importantly, these tests validate the technologies we hope to propose to NASA for eventual flight.
You might remember, in my recent thread, that we might not even have the chance of proposing our mission concept to NASA in the next competition round.
That's something we're working hard on to fix.
But now, for the first time, we know we can fly a variable-altitude balloon.
NASA's #ParkerSolarProbe was able to image the surface of #Venus from space in a way we didn't think possible before!
Here, we can see the Aphrodite Terra highland *glowing* through the clouds (left), exactly where radar data tell us it should be (right)!
Venus' thick cloud layer obscures the surface from space at visible wavelengths—but there are some "windows" at near-infrared wavelengths where cameras can see through to the surface.
PSP took these images at a wavelength not thought to be able to penetrate the clouds before.
This matters because, unlike Mars, Mercury, the Moon, etc, we can't easily see the Venus surface—we have to use radar.
But if we can "see" the surface in the near infrared, we can start to learn things about what it's made of. And thus we can learn new things about Venus.
A quick 🧵 about the *size* of the #HungaTonga eruption:
Volcanic eruptions are generally assigned a VEI—Volcanic Explosivity Index—value.
This scale is a general indicator of the explosive character of an eruptive event.
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This scale, described by Christopher Newhall and Stephen Self in a 1982 paper, is a general indicator of the explosive character of an eruptive event, and reflects the interplay of an eruption's magnitude, intensity, and energy release rate.
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The VEI rating scale employs a set of criteria including ejecta volume, style of eruption, plume height, and injection of gases into the troposphere and stratosphere.
There's no question that the #Tongaeruption was huge—it absolutely was.
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I need you to know I'm being completely serious here.
We have no idea what's inside Uranus.
We really don't have a clue what's inside this or there other "ice giant", Neptune.
It's possible that there's a rocky interior, perhaps at least as large as Earth. There might be a water–ammonia ocean above that rocky centre, topped with a thick atmosphere.
But we don't know.
Uranus and Neptune are the outer Solar System's Venus -- fascinating, largely unexplained, but to be honest pretty much ignored in the modern era of planetary exploration.
The Solar System is *full* of incredible and fascinating worlds!
Mercury.
Venus.
Earth.
The Moon.
Jupiter.
Saturn.
Uranus and Neptune.
Ceres, Vesta, and the other main asteroid belt bodies.
The myriad other minor bodies scattered across the System.
Every one of them amazing! 🥰
People are pointing out that I forgot somewhere important!
Somewhere that fascinates everyone, that we need to explore more, that holds a special place in our heart.