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The Astronomer Who Brought Us the Universe

Posted by timothy on from the and-vice-versa dept.

StartsWithABang writes If all we were able to do was look up at the sky and see what we can see, no matter how powerful our instruments became, we would be extraordinarily limited in what we could learn about the Universe. But if we could know some intrinsic properties about what we were looking at, then simply by measuring things like how bright these objects appear, we could figure out the cosmic distance scale; all it would require is knowledge of a "distance indicator" or "standard candle." The very first one ever discovered — by Henrietta Leavitt — is not only still in use today, but taught us the galactic nature of the spiral nebulae and gave us the expanding Universe.

41 comments

  1. First post by Anonymous Coward · · Score: -1

    Earth?

    1. Re:First post by Anonymous Coward · · Score: -1

      Earth. As well, Systemd.

  2. Much like Systemd, no? by Anonymous Coward · · Score: -1

    I think so

  3. It's big by ArcadeMan · · Score: -1, Offtopic

    Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space. - Douglas Adams, The Hitchhiker's Guide to the Galaxy

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  4. Let me see by Anonymous Coward · · Score: 0

    They explored the universe without leaving the planet? But I've been assured by the Space Nutters that we must explore space and the only way to do it is by setting up a base on Mars?

    1. Re:Let me see by RightwingNutjob · · Score: 4, Informative

      Well, here's where you open yourself up. Distance measurements benefit from longer baselines. The biggest one we have now is about 2AU wide. Take a picture now, wait 6 months, take a picture again when the earth is on the opposite side of the sun. If we have a base on mars, we can have a slightly wider baseline with earth and mars on opposite sides of the sun for a simultaneous measurement (can't do that now at all) and two martian orbital radii for non-simulataneous measurements about a year apart.

      Now you might say: well why can't we do this with a remote probe? And the answer is, of course we can, but it's damn near impossible to be flexible if you launch a satellite into space where you can't get at it to change instruments or reconfigure it. And big mirrors in space aren't anywhere near as easy as big mirrors on the ground. That's why we still build billion-dollar telescopes on the ground, even though we launch billion-dollar telescopes into space. If you had an actual base on mars, with support staff and manufacturing capacity of the sort needed to maintain a remote outpost, you can now have astronomical instrumentation that costs just as much as a space-based platform or a little more, but is worth dozens of space telescopes because it's manned and has the magical property of reconfigurability, repairability, and flexibility in software as well as hardware. So yes, you can do things with manned systems that you cannot do with unmanned systems, especially when you're doing science.

    2. Re:Let me see by Anonymous Coward · · Score: -1

      LOL, what year are you posting from? Technology gets better all the time, remember?

      That's where YOU open yourself up! We just need to send a 3D printer with a FPGA and there's all your instruments we ever need.

      3D printers changed the game, remember?

      LOL

    3. Re:Let me see by RightwingNutjob · · Score: 1

      Well, I'm certainly not posting from the 24th century. So you've got me there.

    4. Re:Let me see by NEDHead · · Score: 1

      Simultaneous? Ain't no such thing...

    5. Re:Let me see by iggymanz · · Score: 1

      Sure there is, for two observers in the same reference frame, even if separated by large distances.

    6. Re:Let me see by PvtVoid · · Score: 2

      Well, here's where you open yourself up. Distance measurements benefit from longer baselines. The biggest one we have now is about 2AU wide. Take a picture now, wait 6 months, take a picture again when the earth is on the opposite side of the sun. If we have a base on mars, we can have a slightly wider baseline with earth and mars on opposite sides of the sun for a simultaneous measurement (can't do that now at all) and two martian orbital radii for non-simulataneous measurements about a year apart.

      Now you might say: well why can't we do this with a remote probe?

      We are: It's called Gaia. The baseline isn't really the limiting factor, nor is mirror size: it's mostly about atmospheric distortion and instrument stability, both of which are vastly improved in space. Gaia will be able to do parallaxes to accuracy of 20 micro-arcseconds.

    7. Re: Let me see by Anonymous Coward · · Score: 0

      They just don't necessarily know until a while later (at a base minimum, without signals via entanglement, of their distance divided by the speed of light) that it was at the same moment.

      Posted anonymously because on Chrome mobile I can apparently no longer log in (ze button! It does nothing!) even once I get the add out of the way of the log in button by tilting my phone into landscape. WTF, Dice.

    8. Re: Let me see by DMUTPeregrine · · Score: 1

      Entanglement can't transmit signals. This is often misunderstood, but it's a big part of the reason why it seems so strange.

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      Not a sentence!
    9. Re:Let me see by NEDHead · · Score: 1

      not even possible to realize 'same reference frame' except in an idealized classroom example unless the two observers are coexisting in the same spot

    10. Re: Let me see by garyisabusyguy · · Score: 1

      Clocks have been the established method for synchronizing measurements along a baseline

      The atomic clocks used for GPS are world beyond the ones used on ships for navigation in ages past, and better clocks are constantly being created

      Sure, it is not as fancy as entaglement, but sometimes a hammer is the only tool that you have

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      Wherever You Go, There You Are
    11. Re:Let me see by Anonymous Coward · · Score: 0

      Mars might be too dusty. Also landing delicate lenses onto Mars would be an engineering nightmare. One of its moons would be easier.

    12. Re:Let me see by Anonymous Coward · · Score: 0

      You're probably off by 300 years...

    13. Re:Let me see by Celarent+Darii · · Score: 1

      The GPS devices that you use would like to differ with you

    14. Re:Let me see by Anonymous Coward · · Score: 0

      You are just sad because your once great country looks like a bunch of pussies because Russia, US, India, Japan and China are doing all the space exploration now. (assuming you are british because of the use of the term "nutters")

    15. Re:Let me see by NEDHead · · Score: 2

      In any real world situation the effects, however minute, of the continually changing local gravitational field due to the motion of all mass and energy will affect the rate of local time and thus will confuse the concept of simultaneity. Only in an unreal highly static situation can you accurately define the idea.

    16. Re:Let me see by Anonymous Coward · · Score: 0

      WHAT space "exploration"? What are you talking about when you use that word?

  5. go expand your own universe! by Anonymous Coward · · Score: 0

    and KEEP OFF MY LAWN!

  6. well, we think we know. by turkeydance · · Score: 2

    when we get there we'll see.

  7. Feminist bullshit by Anonymous Coward · · Score: -1

    yes, I'm sure she worked in complete isolation, and developed everything by herself.

    I'm tired to see these bullshit articles. Like the other one of that supposed astronaut woman who had so many cessna hours she DESERVED to be in space but wasn't because patriarchy.

    I'd say I'm horrified but slashdot has fallen so low it sometimes makes reddit seem like a source for news.

    1. Re:Feminist bullshit by PvtVoid · · Score: 5, Informative

      yes, I'm sure she worked in complete isolation, and developed everything by herself.

      No, she was a part of a group consisting entirely of women under the management of Edward Pickering at Harvard Observatory, called at the time "Pickering's Harem" Despite her groundbreaking accomplishments, Leavitt was unable to obtain a faculty position at Harvard, entirely due to her gender.

      Times have changed a lot since then, despite the efforts of ignorant douchebags like you.

    2. Re:Feminist bullshit by Anonymous Coward · · Score: 0

      That cute girl wouldn't go out with you, huh?

    3. Re:Feminist bullshit by Anonymous Coward · · Score: 0

      So the statement, put enough xxxxxxxs in a room with a computer, one will make productive code in random ?

    4. Re:Feminist bullshit by Anonymous Coward · · Score: -1

      He's not an ignorant douche-bag. He's making the very reasonable (though inaccurate in this case) assumption that this was simply sexist propaganda. It's the sign of the times. I'm in my 50's and I've had racist and sexist propaganda pushed at me all my life. I mean we've had the least competent person in the history of the US in the White House for 6 years because his dad was black. What more proof do you need?

      I know this has nothing to do with what the author of this post was writing about but it's so common I think the response is pretty easy to understand and something many (not brainwashed by the machine we call public school in the US) probably assumed anyway.

    5. Re:Feminist bullshit by tommeke100 · · Score: 2

      The same happened to Marie Curie (you know, the only person to date to win two nobel prizes in different categories and the first to win two alltogether). She was not able to enroll in higher education in Poland because it was not accepting women. Luckily she went to Paris ...

    6. Re:Feminist bullshit by tehcyder · · Score: 1

      I mean we've had the least competent person in the history of the US in the White House for 6 years because his dad was black

      I'm fairly sure George W Bush's father wasn't black, and it was 8 years.

      --
      To have a right to do a thing is not at all the same as to be right in doing it
    7. Re:Feminist bullshit by Arnold+Reinhold · · Score: 3, Insightful

      Leavitt's discovery is on a par with Galileo's discovery of the moons of Jupiter in changing our view of the universe. It combined a brilliant insight, that all the stars in the Small Magellanic Cloud are at about the same distance from Earth, and a lot of hard work analyzing photographic plates. Her measurement tool is still the main one used to determine cosmic distances from beyond the range of stellar parallax out to nearby galaxies, and is used, in turn, to calibrate Type Ia supernova, the standard candle for probing deep into intergalactic space, and back to the Big Bang. Another example of women astronomers getting less recognition than they deserve is Jocelyn Bell, who discovered millisecond pulsars and whose thesis advisor won the Nobel Prize for that discovery.

    8. Re:Feminist bullshit by Anonymous Coward · · Score: 0

      Leavitt's discovery is on a par with Galileo's discovery of the moons of Jupiter in changing our view of the universe. It combined a brilliant insight, that all the stars in the Small Magellanic Cloud are at about the same distance from Earth, and a lot of hard work analyzing photographic plates. Her measurement tool is still the main one used to determine cosmic distances from beyond the range of stellar parallax out to nearby galaxies, and is used, in turn, to calibrate Type Ia supernova, the standard candle for probing deep into intergalactic space, and back to the Big Bang.

      Another example of women astronomers getting less recognition than they deserve is Jocelyn Bell, who discovered millisecond pulsars and whose thesis advisor won the Nobel Prize for that discovery.

      And let's not forget Annie Jump Cannon; she was the creator of the OBAFGKM stellar classification system which is the foundation of the Hertzsprung-Russell diagram.

    9. Re:Feminist bullshit by Anonymous Coward · · Score: 0

      He's not an ignorant douche-bag. He's making the very reasonable (though inaccurate in this case) assumption that this was simply sexist propaganda. It's the sign of the times. I'm in my 50's and I've had racist and sexist propaganda pushed at me all my life. I mean we've had the least competent person in the history of the US in the White House for 6 years because his dad was black. What more proof do you need?

      I know this has nothing to do with what the author of this post was writing about but it's so common I think the response is pretty easy to understand and something many (not brainwashed by the machine we call public school in the US) probably assumed anyway.

      Yes, the poster is an ignorant douche-bag.
      Ignorant because he's wrong and didn't bother to check his facts, and a douche-bag because he's demeaning the work of a person who overcame huge obstacles to produce this work and is dead over 80 years now.

    10. Re:Feminist bullshit by Anonymous Coward · · Score: 0

      yes, I'm sure she worked in complete isolation, and developed everything by herself.

      I'm tired to see these bullshit articles. Like the other one of that supposed astronaut woman who had so many cessna hours she DESERVED to be in space but wasn't because patriarchy.

      I'd say I'm horrified but slashdot has fallen so low it sometimes makes reddit seem like a source for news.

      What supposed astronaut woman are you talking about?

    11. Re:Feminist bullshit by Anonymous Coward · · Score: 0

      I don't know if you misread that person's post.

      Obama, whose father was black, being the LEAST (not most) imcompetent.

    12. Re:Feminist bullshit by ZorglubZ · · Score: 1

      GP Said least competent.

  8. I've seen all of you I need to: by Hartree · · Score: 1

    Oh no! There's a space nutter behind you. Run! Save yourself. I'll try to hold them off.

    Take this tinfoil hat. It may keep them from corrupting you telepathically!

    1. Re:I've seen all of you I need to: by Anonymous Coward · · Score: 0

      What are you prattling on about?

  9. Clickbait by Anonymous Coward · · Score: 0

    Oh slashdot, what have you become? The headline/summary are pure clickbait.

  10. I can't believe people are complaining by cupantae · · Score: 1

    about anything other than the bafflingly irrelevant Wonderwall cover. What is that all about?

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  11. Starts with a Bang ... by RockDoctor · · Score: 1
    ... ends with a Medium article.

    The first online site whose interface is so horrible that I specifically check to see if links go there before refusing to click them.

    --
    Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"