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Tuesday, June 20th, 2017 10:15 pm

Posted by Phil Plait

Astronomers have just announced the discovery of a pretty unusual binary system: A white dwarf and a brown dwarf orbiting each other. That's pretty rare, so as cool as that is — and I'll explain why in a sec — even better is how ridiculously close together they orbit: They're separated by a mere 310,000 kilometers, closer than the Moon is to the Earth! And that means they move around each other fast: The intense gravity of the white dwarf tosses the brown dwarf around it at a speed in excess of 100 kilometers per second. That's rapid enough that they make a complete pass around each other every 71 minutes! Yes, minutes.


There are a few really nifty things about this system, so let's take a closer look. But not too close, because you'll get fried. Let me explain.

First, the white dwarf: It's called WD 1202-024, and it was first discovered in a survey of the sky in 2006. At 2700 light-years from Earth, it's pretty faint; the faintest star you can see with your naked eye is 150,000 times brighter!

Like all white dwarfs, it's the remains of a star that was once much like the Sun but ran out of usable hydrogen fuel in its core. It takes billions of years for a star to get to that point, but in this case WD 1202 reached this stage not too long ago, just 50 million years or so in the past. Normally, when a star like that is all by its lonesome, it responds to losing its fuel by expanding its outer layers, swelling to enormous size and cooling down. We call that a red giant. Over time, the outer layers of the star get blown away, exposing the hot core to space. This core is small (around the size of the Earth) and terribly hot, shining a painful white. That's a white dwarf (and you can find out lots more about them in my episode of Crash Course Astronomy about them).

WD 1202

[WD1202-024 just looks like a white dwarf sitting out there in space, alone and dim. But it harbors a surprising secret. Credit: Rappaport et al., SDSS]

But WD 1202 is different. In this new study, the astronomers discovered it's a variable star, changing its brightness in regular, predictable cycles that take a little over an hour. It slowly and subtly brightens and dims, then, for a few minutes each cycle, the light from the star drops precipitously. That's pretty unusual behavior for a white dwarf, and the astronomers quickly figured out what's going: WD 1202 isn't all by its lonesome. It has a companion: a brown dwarf.

Although the names are similar, they couldn't be more different. Brown dwarfs are objects that are too massive to be planets, but not massive enough to ignite fusion in their cores and become proper stars*. In this case, WD 1202's brown dwarf companion has a mass of about 6.6% of the Sun, which is definitely too low for fusion. It's about 67 times Jupiter's mass, so it's way beefier than a planet, too.

Even though it's far more massive than Jupiter, it's not much bigger (brown dwarfs are weird that way; their cores are very dense and take on odd properties, such that as you add mass to them they actually shrink). But it's still much larger then WD 1202, probably 4 or 5 times wider.

And that's why the brightness of the system changes. Get this: The subtle variations are caused by the brown dwarf itself as it goes around the smaller dwarf. We're seeing its phases!

[The WD 1202-024 light curve is caused by the phases we see of the brown dwarf orbiting the white dwarf, plus a bonus eclipse. Credit: Rappaport, et al. / Bishop's University]

This is just like the Moon, where we see it go through its phase of new (when we only see the dark half), first quarter, full (when we see it fully lit by the Sun), then last quarter, then new again.

But in the case of the brown dwarf we're seeing phases, but because it's reflecting light from WD 1202, but because it's heated to incandescence by it!

The white dwarf is small, but it's furiously hot, about 22,400° C. The side of the brown dwarf facing the white dwarf is heated to glowing. When it's on the other side of the WD 1202 from us we see it full. A quarter of an orbit (about 69 minutes) later it's half full, then another quarter of an orbit after that the unlit side is facing us, so the system is dimmer. After that we start to see the lit side again until it's full, and the cycle repeats.

But there's more. Because the brown dwarf is so much bigger, when it's "new" it actually gets in the way of the white dwarf and blocks its light from us. That's why the brightness drops so much every 71 minutes!

WD 1202 light curve

[The light curve of the binary (the change in brightness over time). The red line is a model that includes the phases of the brown dwarf and the eclipse; the black line is the observations (exposure times are about 30 minutes, so the eclipse isn't seen), and the blue line is the model mathematically fit to the observations (including the exposure time fuzzing out the eclipse). Credit: Rappaport et al. / Bishop's University]

I love just this part of the story. That brown dwarf is far too faint and close to WD 1202 to see it separately, but we can infer its existence because of its phases even though it's 27 quadrillion kilometers away. How about that?

But there's more, and it's also wondrous. Get this: The brown dwarf was, for quite some time, literally inside WD 1202!

Let's rewind the clock back to when WD 1202 was a regular star, about to run out of hydrogen fuel in its core. Back then, the brown dwarf was farther out, probably something like 50 million kilometers out (or half the distance from the Earth to the Sun), well separated.

But then WD 1202 expanded into a red giant. These kinds of stars get really big, easily spanning a hundred million kilometers across, sometimes more than twice that. That's bigger than the orbital distance of the brown dwarf, so when the primary expanded, it engulfed the brown dwarf.

Yet it persisted. That's because when it expands, the density of the gas in the red giant's outer layers dropped hugely. The lower density is what saved the brown dwarf from destruction. It would've been heated a lot by the star around it, and the drag from plowing through the material would have shrunk its orbit. As it got closer it would have orbited faster than the red giant rotated, too, so the companion acted like an egg beater, stirring up the primaries outer layers.

That can give the gas so much energy that they are expelled even more rapidly. When this violent period in the binary's life was over, what was left was the white dwarf with the companion brown dwarf in its tight orbit. Judging from what we know about the physics of such events, and the temperature of the white dwarf (they cool over time, giving us a measure of their age) this happened about 50 million years ago.

That's seriously cool. And yet there's one more thing.

[Artist's drawing of the RS Ophiuchi system, a similar one to what WD 1202 will be like in a couple of hundred million years. Credit: David Hardy & PPARC]

The gravity of the white dwarf is impressive. When you squeeze half the mass of the Sun into a ball about twice the size of the Earth, it's phenomenally dense. The surface gravity is tens of thousands times stronger than Earth's. If you stood on its surface, you'd weigh thousands of tons. Oof.

As it happens, the brown dwarf is orbiting so close to WD 1202 that its gravity is felt very strongly indeed. Over time, even now, the brown dwarf is slowly spiraling in, getting closer to the white dwarf as they emit gravitational radiation (for more about that, read this article about gravitational waves). The astronomers who observed the system calculate that in about 250 million years, the brown dwarf will get so close to the primary that the white dwarf's gravity will start to draw material off the companion!

This material will pile up on the white dwarf and get squeezed excruciatingly hard by the intense gravity. When there's enough, it will undergo sudden and catastrophic hydrogen fusion, exploding literally like a thermonuclear bomb. This explosion is very energetic, and the system will dramatically flare in brightness. Then it will fade as the material blown off cools and blows away … and then the cycle will star again.

This kind of object is called a cataclysmic variable, or CV, and we know of quite a few. We also know of a few pre-CV systems, but this one has the shortest period of any known, which means it's the closest we know of that will become a proper CV in the future.

So, as amazing as this system's history is, and is now, its future will still hold plenty of wonder. As long as you stand a bit back from it. Cataclysmic variable are given that name for a very good reason.

This is one of those science stories were I dig every piece of it. It's got quite a bit of the stuff I love: stellar evolution, weird objects, cool geometry, and it ends quite literally with a bang.

The Universe is a pretty interesting and astonishing place, if you look at it carefully enough.

*Some people call them "failed stars", which is a term I don't like, for two reasons: They aren't stars at all, they're their own class of object; and why call them that when you could be more positive and call them really overachieving planets?


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Thursday, June 22nd, 2017 01:45 pm

Posted by Ariel Meadow Stallings

New Orleans meets pop culture meets foodie details at this Atlanta wedding
Photo by Peach and Oak photographer from this wedding we featured a couple of weeks ago.

Hi, I read an article recently (Excluded by the wedding industry, black brides turn to Instagram) and wondered what your thoughts might be on it.

I love your blog (it's the only wedding thing I'm subscribed to) but surely there must be more black Offbeat Brides out there somewhere.


Hey, Emma! Thanks for sharing that article — super interesting. This is an issue I feel pretty strongly about, and have been writing about for almost a decade. Here's a post from way back in 2008, where I was like "Where the fuck are the Offbeat Brides of color?"

I can say that, in reviewing our submissions, we feature virtually every single black Offbeat Bride wedding that's submitted to us, because it's a huge editorial priority. In fact, we skew so hard toward trying to represent black brides on the site that sometimes we have commenters saying things like, "There's nothing offbeat about this wedding, it's totally boring, why is this even on Offbeat Bride?"

Our answer is always, "Because we're trying to ensure that our site is a place where folks who feel under-represented in the mainstream wedding media can feel seen."

We also heavily favor weddings that include people with disabilities, non-binary genders, and older couples, even though historically these posts don't perform all that well. As a publisher whose business lives and dies by pageviews, it's scary to say "Sure, let's pass up that pink-haired unicorn wedding that'll get 10k views, and instead feature this lower-budget backyard wedding of this older disabled couple that will probably only get 500 views" …but that's the kind of editorial decision we've made every week, for many years.

I don't mean to sound all OH I'M SO NOBLE, here — in fact, far from that, prioritizing content in this way can feel pretty awkward at times. There's an odd grey area where it feels like tokenism. I've wrestled with that discomfort for years, and wrote about that a bit over here in 2012… and five years later, I'm still not sure I have a solid solution.

To more specifically answer your question about where the black Offbeat Brides are: while we don't tag weddings specifically for black brides (categorization in this way can bring up complex issues around self-identification), we do have a couple overlapping archives where you'll find them: the couples of color archive, and our natural hair archive.

Now, as for that article you shared! Super awesome! …for the most part. I love love love that communities that feel under-represented in the mainstream media are using Instagram to get their stories out there and increase visibility… I especially love how I've seen youth dealing with disabilities and chronic illness using Instagram. It's a form of body positivity that's so needed, and I love that social media can amplify those voices that aren't getting heard.

That said, it's a bit weird to see that article give so much credit to Instagram. One of the Instagram accounts mentioned, Munaluchi Bride, is actually a website that's been online since 2009! This means the article is essentially the author saying "I found things on Instagram that I could have found on a website, but I like browsing via social media better." …And that's cool! I totally get that there are tens of thousands of people who follow Offbeat Bride on Instagram who never visit our website. It just seems a little weird to point to Instagram as some sort of new and exciting answer, when publishers like Munaluchi have been featuring the weddings of people of color since before Instagram existed.

But whatever: if Instagram is the tool that helps people find more inclusive content in the thick of their wedding planning, I'm all for it!

Thursday, June 22nd, 2017 01:00 pm

Posted by Jen

I believe that all new scientific discoveries should be announced via cake, don't you?

[pushing back glasses and consulting clipboard] Ladies and gentlemen, I'm proud to present...

The Majestic Bagel-Nosed Falcon of Uganda!

Or it might be a fish. Fish...falcon...you know. Whatevs.


[Shuffling papers] Next we have...

The Majestic Happy Chicken-Footed Spiny-Backed Slime Devil.
(Watch out; they spit.)


We're still working on the scientific name for this one:

So for now let's just call it the Majestic Coiled Crap Hound.
(I think that has a real ring to it, don't you?)


Here we have a particularly colorful specimen:

The Majestic Disco Newt! Let's pause a moment to admire his beautiful plumage.

Right. That's long enough.


And finally, we have...

The Majestic Three-Toed Four-Eyed Whiskered Zebra Toad.
(Yeah, you heard me. ZooBorns, eat your heart out.)


Thanks to Kelly D., Kit R., Caitlin B., Jordan J. and Donald L., who are all, er, majestic.


Thank you for using our Amazon links to shop! USA, UK, Canada.

Thursday, June 22nd, 2017 12:45 pm

Posted by Offbeat Editors

Art, succulents, & a crystal crown at this vegan eco-friendly wedding
Photos by Aleah Eileen Photography

The Offbeat Bride: Kiara, musician

Her offbeat partner: Kiel, musician

Date and location of wedding: Elysian Park, Los Angeles, CA — April 23, 2017

Budget: $2,175

Our offbeat wedding at a glance:

Our rogue park wedding idea was born from there being a few things that are really important to us in our day-to-day lives, and we wanted to be able to honor those in our wedding.

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

We both are vegan and lead lives of compassion towards ourselves and living beings around us. From the beginning, we were sure we wanted a 100% vegan wedding, from what we wore to what we ate. We sourced our shoes from awesome vegan shoe companies, my dress was made with synthetic fibers, and Kiel's suit is a cotton blend. We care about the preservation of our earth and environment and wanted to have a low impact, eco-friendly, and minimal waste day, so our plates, napkins, and cups were all compostable, and our venue was provided graciously by Mother Earth.

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

We gave away all our extra food and flowers to our guests and the fleece blankets we made to be used as picnic blankets were donated to a woman’s shelter after the wedding. Above all, we wanted the day to be about our love for each other and our love for our community that surrounds, supports, and holds us accountable.

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Tell us about the ceremony:

We had an intimate ceremony in a circle. Ben, the guy who didn’t really mean to introduce us four years ago when we were both playing in his band for his CD release party, was our loving officiant. We walked into the circle of our community to our friend Ryan Dilmore singing his song, "Forever Sounds (So Much Like Your Name)." After the kiss, our friends, "Sometimes We Sing Together," came into the center for a beautiful rendition of their song "Pyramids." These artists and songs speak to Kiel and myself in the way they discuss love, openness, and adventure.

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

In addition to our own vows to each other, Kiel and I had prepared community affirmations where we asked our community to exclaim "We Will!" to a list of requests to support us in our marriage. There was a mat that the guests were asked to sign at the reception and our affirmations are being artistically rendered and will hang in our home surrounded by the signatures.

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

After the final song and a large group hug, it was time for the reception!

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Tell us about your reception:

Many two- and four-legged creatures gathered in the park on a gorgeous spring afternoon. It was magical. With dietary restrictions, wanting to keep the day as simple and waste-free as possible, and pure cost considerations, we decided to keep the wedding in the middle of the day and provide vegan snacks, lemonade and iced tea, and vegan cupcakes and invite our guests to bring their own libations and a picnic if they wished.

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

I think art is a wonderful way for people to connect or become acquainted, so we had two art tables. Guests were asked to bring a little succulent plant. At the Succulent City table they painted the pot, and when they went home, they were invited to take home someone else’s painted, potted succulent as a fond memory of the day. The other art table was our Memory Book, where each guest was asked to create a page. They were invited to bring something physical like a photo, poem, letter, etc. to assist their page, or they could use the art supplies provided to create their masterpiece. The book is so beautiful; each page different and unique, just like our eclectic community.

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

What was your most important lesson learned?

It truly takes a village. The most important thing to me was that our community was around us and that everyone could have a relaxing and fun day. My family arrived super early at the park that morning to stake out our area. When I had to go up to the house to get ready, the park wasn't set up. Until that point, I had had 100% control over everything and this was when I had to take a deep breath and just let go. While I was sitting still and getting my hair and makeup done, my incredible mother and friends made my bouquet, Kiel's boutonniere, table arrangements, and set up our park site.

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

When I got down to the park for our first look, everything looked perfect. I walked through the grass towards Kiel’s back, locking eyes with our dear friends who were finding their individualized notes that we’d handwritten in the ceremony circle. The sun was shining but shade was abundant and there was a beautiful, soft breeze. That little bit of letting go, of letting my community take over and make those final decisions, brought the final touch of magic into this fairy tale day for us.

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding

Art, succulents, & a crystal crown at this vegan eco-friendly wedding



Click to view slideshow.
Thursday, June 22nd, 2017 11:45 am

Posted by Adiba Nelson

Meet ClaraBelle Blue

One of the high points in parenting is getting to read books to, and with, your child. It is a bedtime ritual that has been practiced for decades upon decades. Whether it was "The Adventures of Dick and Jane," or the now ever-popular "Harry Potter" series, books at bedtime are a staple in a household with children.

However, when I went looking for a bedtime book that I felt my child could relate to, I came up short. Actually, I came up empty. I searched local independent bookstores, well-known chain bookstores like Barnes & Noble, and even online looking for a book that had an African American girl in a wheelchair on the cover, and quickly discovered there was nothing. It simply did not exist.

Let me put this in a broader context: My child did not exist in the books written and designed for a group that she is clearly a part of: children.

While I did find books that talked about children having a disability, the books often focused on the child's disability, and never the child. This would never do for my kid. At the time, my Emory was a spunky, sassy four-year-old (not much has changed four years later) who was so much more than just her wheelchair or communication device. So, I decided to take matters into my own hands. I wanted a book that told me about a kid being a kid, doing kid things. It was fine if there was a message because as a writer, I do feel like children's books should have a point, but I mostly wanted her to see herself — a fun, loving, silly kid, who, by the way, also had special needs.

As I shopped the book around to a few agents, I found out why books like mine are not included. My child, and children like mine (and possibly yours), are considered too "niche" for the publishing world.

Thus, "Meet ClaraBelle Blue" was born.

Now, truth be told, I wrote it in a fit of frustration (and maybe a little bit of mama bear rage). How could an entire genre of books that is supposed to serve my child, not include my child? It didn't make sense and seemed terribly cruel and unfair. As I shopped the book around to a few agents, I found out why books like mine are not included. My child, and children like mine (and possibly yours), are considered too "niche" for the publishing world.

I remember the feeling that came over me when I heard those words through the phone line. It was akin to the feeling I had when a child care center once told me that my child was a safety hazard because another child might trip and fall over her stander — therefore at age two, she had to remain in the infant room. That feeling? You might be familiar with it. It's rage. It's pain. It's frustration. It is a heartbreaking sadness. And if you're anything like me, it culminates into the fiercest determination this world has ever seen. Nothing about my child, or any child is "too niche" to be seen in a children's book, and no child is too niche to be recognized as existing in the world they live in.

This awoke a giant in me, and I decided to self-publish "Meet ClaraBelle Blue." My book is currently the only children's book featuring a young African-American girl with special needs on the cover, and, once you read the book, you quickly discover that it just may be the only book of its nature. This book that was once labeled as "too niche" to be considered for representation has quickly become not only my daughter's favorite book, but a favorite in households across the country.

With "Meet ClaraBelle Blue", I set out to not only create a book that my daughter could see herself in, but also a book that could help typically-abled children see that children like her aren't so different from them, even though they may look (or behave) differently (there's that whole "message" thing). Inadvertently, the book has also helped parents start the conversation around special needs, and keep it at a child-friendly level.

My goal is to have "Meet ClaraBelle Blue" on every child's bookshelf, and in every library and bookstore across the country because I know the story of a kid just being a kid is not "too niche" for kids to understand.

My kid is not too niche. Your child is not too niche.

And it's high time the world found out.

Thursday, June 22nd, 2017 12:41 pm

Posted by (@NWSBayArea)

Very hot today with triple digit temperatures fcst for many inland areas. Tomorrow will mark the beginning of a several day cooling trend.

Thursday, June 22nd, 2017 11:17 am

Posted by (@NWSBayArea)

At 3 am some sites in the North Bay hills are still above 90! with lots of 80s across the Bay Area hills. Expect another hot day inland!