Decoding Nebulae

We can agree that nebulae are some of the most majestic-looking objects in the universe. But what are they exactly? Nebulae are giant clouds of gas and dust in space. They’re commonly associated with two parts of the life cycle of stars: First, they can be nurseries forming new baby stars. Second, expanding clouds of gas and dust can mark where stars have died.

Not all nebulae are alike, and their different appearances tell us what's happening around them. Since not all nebulae emit light of their own, there are different ways that the clouds of gas and dust reveal themselves. Some nebulae scatter the light of stars hiding in or near them. These are called reflection nebulae and are a bit like seeing a street lamp illuminate the fog around it.

In another type, called emission nebulae, stars heat up the clouds of gas, whose chemicals respond by glowing in different colors. Think of it like a neon sign hanging in a shop window!

Finally there are nebulae with dust so thick that we’re unable to see the visible light from young stars shine through it. These are called dark nebulae.

Our missions help us see nebulae and identify the different elements that oftentimes light them up.

The Hubble Space Telescope is able to observe the cosmos in multiple wavelengths of light, ranging from ultraviolet, visible, and near-infrared. Hubble peered at the iconic Eagle Nebula in visible and infrared light, revealing these grand spires of dust and countless stars within and around them.

The Chandra X-ray Observatory studies the universe in X-ray light! The spacecraft is helping scientists see features within nebulae that might otherwise be hidden by gas and dust when viewed in longer wavelengths like visible and infrared light. In the Crab Nebula, Chandra sees high-energy X-rays from a pulsar (a type of rapidly spinning neutron star, which is the crushed, city-sized core of a star that exploded as a supernova).

The James Webb Space Telescope will primarily observe the infrared universe. With Webb, scientists will peer deep into clouds of dust and gas to study how stars and planetary systems form.

The Spitzer Space Telescope studied the cosmos for over 16 years before retiring in 2020. With the help of its detectors, Spitzer revealed unknown materials hiding in nebulae — like oddly-shaped molecules and soot-like materials, which were found in the California Nebula.

Studying nebulae helps scientists understand the life cycle of stars. Did you know our Sun got its start in a stellar nursery? Over 4.5 billion years ago, some gas and dust in a nebula clumped together due to gravity, and a baby Sun was born. The process to form a baby star itself can take a million years or more!

After billions more years, our Sun will eventually puff into a huge red giant star before leaving behind a beautiful planetary nebula (so-called because astronomers looking through early telescopes thought they resembled planets), along with a small, dense object called a white dwarf that will cool down very slowly. In fact, we don’t think the universe is old enough yet for any white dwarfs to have cooled down completely.

Since the Sun will live so much longer than us, scientists can't observe its whole life cycle directly ... but they can study tons of other stars and nebulae at different phases of their lives and draw conclusions about where our Sun came from and where it's headed. While studying nebulae, we’re seeing the past, present, and future of our Sun and trillions of others like it in the cosmos.

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when ezri says “these pronouns are going to drive me crazy” and “it’s like i don’t know my own body” and “there’s days when the computer asks me to identify myself and i don’t know what to say” and “i’m still sorting out my pronouns” and “there’s days when i don’t even know if i’m a man or a woman” hhhhhhh i cast trans your gender

This lighthearted post sent me down a Trill Feelings rabbit hole this morning, so I’m going for it: 

Ezri's self-interrogation about pronouns and gender is a big trans mood, for me and, clearly, for other folks. I mean, it’s right there in the text, whether or not the writers were aware of it at the time.

Oddly enough, though, Jadzia is the Trill I turn to as a reflection of my specific experience of being nonbinary. There are, of course, instances where they (I'm going to go ahead and use 'they' here) adopt binary terms for themself. They refer to themself not infrequently as a woman, and there’s the whole 'I am Dax, godfather of your son' thing--given the way Klingon culture is depicted in DS9, I assume ‘godfather’ is a gendered role. But I feel like you can read something wry and knowing in the way they self-declare. Something, dare I say, almost camp. When they do call themself a woman, e.g., they’re most often prodding at male characters’ insecurities (’This is where we make our graceful exit and let the boys talk amongst themselves,’ to Kira re O’Brien and Sisko, in ‘House of Quark; ‘I’m not a Klingon warrior, I’m a beautiful and sensitive young woman’ to Worf, in ‘Bar Association’). And while those lines were probably written as either gender-essentialist jokes about women, or as a woman joking about gender essentialism, I see those comments in context as a kind of ironic self-distancing that echoes the way I deal with being gendered. Like Jadzia is playing with the fact that Humans and Klingons see their body as female--and them as a woman--when of course their body is also a worm’s body and their joined sense of self is pretty much opaque to any non-joined species. 

I read them, in other words, as a character for whom gender is a bit bemusing, who’s not too bothered about being perceived as a woman or a man but likes to shake people up about it, and who is generally at home in their ambivalent, multiple body. And seeing someone with that sensibility onscreen--a sensibility that’s adjacent to my own, though refracted through the figure of the symbiont--feels very unusual and important to me.    

An obligatory caveat: I’m not arguing that this is the way Jadzia was meant to be read, or should be read. When there are all of two women in DS9′s Ops, the last thing I want to do is diminish the significance of them (her) as a woman, and a wlw character. And given the politics of representation in fandom I wavered for a long time about posting this, for exactly those reasons. But I found it really interesting trying to excavate why Jadzia speaks to me more than Ezri--whom I love as a character and who invites a textually-supported trans reading--or even than the ‘canonically’ nonbinary Adira Tal. To me, I think, implication often feels more immediate than representation, and Jadzia Dax, with all their contradictions, is particularly rich in trans implication.