https://arxiv.org/abs/1801.01120
Is it cheating if I read the SciTech Daily article first?
Only if you still write it up.
Honest.
(We've both let this slide lately [I wasn't entirely kidding about a short Horkheimer version], and really ought to dedicate a thread, since you need to write up science outside your expertise if that's a thing you fancy trying to make money at... You're quite smart, even by the standards of this community, and clearly well-read; I think you could swing the archaeology papers, notwithstanding the difference in jargon and rigor.)
I've changed my mind. It's nothing but clear that pro science writers read each other's stuff all the time. Have a look at that SciTech Daily article and party on with your own bad self.
So I didn't read that article specifically, but I have been following this story. Nevertheless, here's my take:
In the 1920s, Hubble famously discovered the expansion of the universe by looking at Cepheid variables in other galaxies. Cepheid variables are standard candles, which is what astronomers use to measure cosmic distances. Because a star that looks bright might be a close, dim star or a distant, luminous star, we need a way to independently determine how bright a star should be in order to figure out how far away it is. Cepheid variables serve as a standard candle because their brightness periodically pulsates and there is a correlation between the pulsation period and its average peak brightness. So the longer the period, the brighter a Cepheid should be, which means that if you find a dim, long period Cepheid, you know it must be very far away.
The tricky part is that in order to calibrate "very far away," you have to know the actual distances to some nearby Cepheids by some other method. This is the cosmic distance ladder, by which we climb one distance-measuring rung to reach the next. For the closest interstellar objects, we measure distance by "parallax," which in practice is a kind of vague term that corresponds to any method that uses a combination of time and geometry. The distances to the Cepheids Hubble used were actually determined via "statistical parallax," which is a little complicated and not central to this story. (See this (http://anomalous-readings.blogspot.com/2017/05/rungs-all-way-down.html) post if you want to get a better idea. Although I'm not super happy about how that one turned out.)
When you hear the term parallax, what probably springs to mind is what astronomers refer to as "stellar parallax," which is observing the apparent shift of a foreground star against background stars as the Earth moves around its orbit. Measure the position of a star. Wait half a year. Measure again. The greater the difference between the star's two apparent positions, the closer it is. This paper details a very precise set of stellar parallax observations made using the Hubble telescope. I'll talk about why these measurements are so good in a bit, but we're not quite done with Hubble the dude.
Hubble's discovery required accurate distance measurements and accurate spectroscopy. The faster a star is receding from you, the redder its spectrum will be due to the Doppler shift (redshift for astronomy). What Hubble found was a roughly linear relationship between distance and recession speed. A galaxy twice as far away as another will be receding at twice the speed. Combine this with some fancy math from general relativity and you can conclude that the universe is expanding and must have been smaller in the past. The expansion rate is now referred to as Hubble's constant. However, due to some systematic errors present at the time (for example, there were Cepheids that behaved differently from the rest, but no one knew it then), Hubble's estimate was an order of magnitude too high.
In the decades that followed, astronomers were able to get a much more accurate value for Hubble's constant and were also able to extend it out across the entire cosmos. They achieved this by finding more standard candles, the most important of which is type 1a supernovae. These work as standard candles out to much greater distances than Cepheids because they are extremely luminous and they have a fairly well understood peak luminosity based on underlying physics. Using these supernovae, astronomers were able to show that Hubble's constant is in fact pretty constant over long stretches of time and space. Cool.
So there are two reasons why the most recent Hubble observations are able to pin down a value for Hubble's constant with even less uncertainty. The first has to do with consistency. They measured the parallax of Milky Way Cepheid variables using the same Hubble camera that's been used to measure the brightness of extragalactic Cepheids. This means they can be very confident that discrepancies aren't just due to using different instruments.
Second, they're also using a relatively new technique for taking pictures with Hubble called spatial scanning photometry. Rather than just staring at a star and collecting its light over a period of time, they get Hubble to scan diagonally over it, leaving a star trail on the CCD and then adding up all the light from the trail. The advantage of this method is that you can collect a lot of light from a single source without saturating your pixels and you're not relying on one group of pixels to calculate the brightness of the star. You can average out the brightness across this diagonal pixel slash in a way that reduces the chance for error due to (essentially) imperfect calibration.
So the team got very precise measurements of the brightness and parallax of Milky Way Cepheid variables, which let them recalibrate the cosmic distance ladder all the way out to type 1a supernovae and come up with an even better measurement of Hubble's constant. Great. The reason this story is making headlines, however, is that it widens and solidifies the gap growing between this method of determining Hubble's constant and another method.
Let's flash back to Hubble the dude for a moment. He discovers the expansion of the universe, and theorists run with this idea and postulate a big bang. A big bang should leave behind observational evidence in the form of the cosmic microwave background, which formed when the universe cooled down enough so that electrons could calmly orbit protons and photons could stream outward without fear of hitting those electrons. Some of the static on your TV that nobody sees anymore because we've all gone digital is a result of CMB photons reuniting with matter for the first time in like 13.7 billion years, having cooled down to 2.7 kelvins.
But with very good satellites and other radio/microwave telescopes, we can detect much more than static in the CMB. There are tiny temperature fluctuations, some of them on large scales, others on small scales. You can plot all these variations as a power spectrum, which measures how strong your fluctuations are at particular sizes. The exact shape of this spectrum depends on a variety of factors, but cosmologists can model what it should look like using relatively simple physics.
One of the primary parameters influencing the CMB power spectrum is the ratio of matter and energy when the CMB formed. Before the CMB, matter and photons bounced around in a big sloshy mix that caused reverberations throughout the cosmos. Once the CMB formed, they separated and stopped influencing each other. The result is that the CMB power spectrum encodes the matter and energy waves that were most prominent at that last moment of scattering, so the ratio of matter to energy tells you what kind of waves you should get.
The big bang says the universe started out with more energy (from photons and neutrinos) than regular matter. However, as the universe expands, energy dilutes more quickly than matter (due to redshift), which means that at some point, matter becomes more dominant than energy. The ratio of matter to energy that you get from the CMB tells you when this happens, which tells you how quickly the universe is expanding, which gets you another estimate of Hubble's constant. (The difficult part is that many factors go into the CMB power spectrum, so this really gives you a range of acceptable values for the Hubble constant as those other parameters slide around.)
And the problem is that as more accurate maps of the CMB have been drawn (from WMAP and Planck), the value of Hubble's constant they're getting and the value coming from type 1a supernovae have stopped overlapping. The CMB gets you 67 km/s/Mpc, and this new paper's recalibration of Cepheid variables gets you 73 km/s/Mpc, and the uncertainties have shrunk enough that you can't just hope they're really the same value. So there's something important that cosmologists are missing. Thanks to efforts like this most recent paper, measurement error is probably not the answer. Maybe new physics? Maybe assumptions underlying one or both methods are wrong? No one is really sure yet. It's a pickle.
Wow that was way too long. I'll see if I can put together a shorter version later.
Your language is good, but I'm going to need to teach you some news/journalism style. You want to begin with a "lede", which is one sentence, concise as humanly possible without being misleadingly simple, with a summary of, and/or hook for, the article's idea(s).
Skimming the beginning, you need to say "astronomer Edwin Hubble" to avoid confusion with his eponymous space telescope. At the mention of six months later for parallax. you probably ought to work in as briefly as possible that it's opposite side of orbit = greatest distance baseline.
I mean, in general, you want to cut where feasible, simplifying, but also idiot-proofing.
I'll try hard to give you an in-depth reading and a lot more feedback later today when I'm caught up on my daily routine.
Protip: Always come up with a headline or two - not just for presentation here, but because even good editors sometimes come up with a head that misses the point and/or is a lame joke and/or chaps your butt some other way; it is standard practice to end you copy with some suggested headlines, which they may actually use instead of inventing something embarrassing. Here, you'll want to bold your favorite at the top - but just as well get in the habit of putting any other head ideas at the bottom.
I should quote the journal link and these two posts to the dedicated thread, so we can go on from there there, shouldn't I?
I want to get paid to write about science. At least in the short to medium term, I'm not picky about how that happens. I can write for newspapers/magazines by pitching, I can write press releases for universities, I can do outreach for scientific organizations and agencies, etc. But as BU pointed out, those all require different audiences.The more I know about your goals and general druthers, the better I can be of help, so this is great.
Personally, there are two-ish ways I'd like to write about science: (1) provide slightly meatier explanations for people who get fed up with bad/lazy science articles but don't want to wade into journal papers (basically me before I went back to school), (2) tell stories about how science gets done, focusing on the process and pitfalls more than on big, flashy, speculative results.
write press releases for universities, I can do outreach for scientific organizations and agencies, etcWhen I was a junior reporter, I'd occasionally get handed press releases to rewrite into articles. I was appalled by how few PR flacks in town knew the basic AP stylebook stuff. About a decade and half later, I was secretary of the chess club in the same small city/big town -pop. aprox. 30,000- and taking initiative to be the one promoting the club, when we put on a simul, or tournament, or whatever mildly newsworthy/promotable event, I DID know the basic newswriting format, and was pleasantly surprised to find a lot of my emailed press releases run verbatim in papers in town -and somewhat around the region- when they got any traction at all. I do not know, but imagine that that's a lot less likely along the highly-urbanized mid-Atlantic coast area well south of New York - but I also imagine the standards for professional press-release writing PR flacks are a lot higher, and releases without proper news format get treated with a lot less respect at the news venue end. I know I didn't respect what I was re-writing where I was.
It's that way because -dig this- a correspondent sending a story long-distance by telegraph needs to get the most important info across first in case Indians cut the line or something, and the paper back home only got the beginning of it...
I kid you not.
Y'know, I could do you a re-write in news style for you to compare; does that sound worthwhile?
So, the next time I see something astronomical getting heavy coverage and the one I pick has a journal link, how about I post everything I find here for style comparison, and if you're willing, you write it up, too.
We can also girldog about the bad write-ups for both education and fun, which should rope in Uno and Geo for sure.
..., 'cause Geo likes to go in the backyard at night and look up and I copy/paste more of those stories than I would otherwise.
Yo, the gatekeeping function is important is all; you can't cover everything, so just as well keep in mind what getting the light shined on it will do some good for the world.And on a libertarian sort of note, you're a man, not a lemming; to the extent you have any freedom in a science writer gig, even when you know pointing the light where you're choosing won't do any good, you should AT LEAST choose to not be part of the problem when the lemmings are shining it where it's doing harm.
Re: monkeys, animal cognition (and cognition in general) is very fascinating to me and I'd certainly like to shine some light on that. The moral/advocacy aspect of it is something I'd like to avoid in general, though. I'm much more interested in giving people (a) the tools required to debate something thoughtfully and (b) the facts required to participate in the debate. This is where the philosophical side of me comes in. It's too easy for me to take an issue like animal rights and explode it into an entire discussion of other minds, AI, epistemology, and skepticism, at which point the very practical question of how we should treat animal X seems (to me) distant and meaningless.Isn't that what I said?
A thing to be thinking, meanwhile, is about how you approach a science write-up thematically for a broad audience. You need to figure out going in what the 'hook' is; what about it is of interest to the great unwashed, both the general public and especially them of us as has no particular science education but read science articles anyway. What's weird, wild, and/or 'sexy' about it? Is it the cause of anything laymen know about IRL? Does it make anything light up or help explain life the universe and everything? Are there any technology implications/possible advances in anything people have or encounter IRL?What's the central point of what you're translating? Give it in one sentence before you start elaborating into an article. -Now throw that one out and give us a short sentence in baby-talk.- Try writing suggested headlines before you start the rest (you can always add more later as they strike you, and they will, but this is for focus and inspiration).
You've been a little ruined by your academic training, that you write science consistently to prove your case, not just to explain that bit of science.. You're going to have to focus.
Well, I think I'd hate myself even if I weren't a Jew. ;)
Lori, I know you well enough to be near 100% sure that you instantly blew the above off as trite-ish and not the right tack for you and your strengths and weaknesses...Well, I think I'd hate myself even if I weren't a Jew. ;)
I'll take you at your word.
But it doesn't have to stay that way. I know it's uncomfortable for introverts like us, but by sustaining an effort to be kind/nice to people, talking to and smiling at strangers- both you and others will feel better about you. I had a sales job after working more or less alone for 20 years. I had to learn to connect with people, so I practiced everywhere I went. A simple good morning, weather comment, or, being a scientist with mad observation skills- you can find something to sincerely compliment.
It's not easy, but it gets easier. When you see somebody's face light up when you tell them that you hope you have hair as great as they do when you reach their age, it will make both of your days.
You managed your move, you can do this, too!
(Oh, and is the email with your account here any good, or would I need to dig up the time Elok cc:ed us if I wanted to email you?)Something odd was going on with my email account; it ate the first two tries w/o appearing in Sent messages, and I have no way of knowing if you got the third try, as Elok did. -Go check Writers' Workshop, willya? I finished reading last night.