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Not the Bees!!! [SCIENCE]

QuestionMarkManQuestionMarkMan Registered User regular
edited March 2010 in Social Entropy++
SCIENCE
For decades astronomers have used the Astronomical Magnitude Scale to measure the brightness of stars. But what if they're measuring with an inaccurate ruler? And how could that screw up the quest to understand dark energy?

The Astronomical Magnitude Scale (see bottom of post) is a logarithmic scale used to measure the brightness of stars as seen from earth. The sun, our nearest star, is set at a value of roughly -27, but humans anywhere on earth can comfortably see all the way down to a value of zero. For values of +1 to +7, an observer would have to be in the country, away from light pollution. Trying to see anything brighter than +7 would mean breaking out the telescopes.

Scientists measure the brightness of astronomical objects by comparing the object's brightness to the brightness of reference stars. Vega and Sirius are popular references, since they have defined and well-known magnitudes.

Or do they? Despite the many advances in the practice, focus, and breadth of knowledge of astronomy, the apparent magnitude values of stars have been updated haphazardly, or not at all.

This faulty measuring system has bigger consequences than missing a twinkle or two. Astronomers use apparent magnitude to judge the distance of stars. Far-away stars are measured by determining their color spectrum and their apparent magnitude. The color spectrum of a star can tell scientists how bright it is. Why, then, do we need the Astronomical Magnitude Scale? Because it, in combination with the knowledge of the absolute brightness of a star, helps scientists determine how far away that star is.

A light that's shining in a person's face from two feet away is uncomfortable. From twenty feet away, it's enough to read by. From two hundred feet away, it's just a glimmer. By combining the knowledge of how bright the light is (spotlight, 60 watt bulb, candle flame) and how bright it appears, a person can roughly judge the distance from them to a light. Astronomers use the same process to determine how far away a star is. Imagine, however, that all throughout a person's life, they were told that a ten watt bulb was actually 60 watts. Their entire scale of reference would be thrown off, making it impossible for them to judge the distance of lights.

Once distance goes out the window, many measurements of the effects of dark energy go right out with it. Dark energy is the mysterious force that seems to be making the universe expand faster and faster over time. Scientists use the distance of stars to measure this expansion.

Picture yourself sitting on a rubber band as it is being stretched. Objects that are close by will be receding away at a certain rate of acceleration. However, objects that are farther away will be receding at a faster rate than nearby objects, because every part of the rubber band is expanding. The farther away an object is, the more material between it and you will be stretching out and pushing you apart.

If a scientist were to look at a star they mistakenly think is close by, and see it receding at an unexpectedly fast rate, they will come to erroneous conclusions about how fast the universe is expanding, and how great the force of dark energy is.

For want of a nail, the cosmological constant is lost.

Fortunately, there is a mission planned to take more accurate measurements of reference stars. Absolute Color Calibration Experiment for Standard Stars, or ACCESS, will give accurate and up-to-date information on the magnitude of the stars, and set a standard that can be used to give all scientists consistent data, and let all stargazers know exactly what they're seeing, and where they are seeing it.
500x_magnitude_scale_02a.jpg

New Scientist talks about it, as does Harvard, and How Stuff Works

QuestionMarkMan on
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Posts

  • UsagiUsagi Nah Registered User regular
    edited February 2010
    and QMark comes through with the Science thread!

    I was at an astronomy lecture last year and I remember the speaker talking about difficulties with measuring relative magnitudes especially in close clusters of stars, so this would be very neat if ACCESS could simplify things a bit

    Usagi on
  • QuestionMarkManQuestionMarkMan Registered User regular
    edited February 2010
    I want to make a big post later about Science heartthrob Dr. Brian Cox

    QuestionMarkMan on
  • PiptheFairPiptheFair Frequently not in boats. Registered User regular
    edited February 2010
    science is gay

    alchemy is where it's at

    PiptheFair on
  • UsagiUsagi Nah Registered User regular
    edited February 2010
    I want to make a big post later about Science heartthrob Dr. Brian Cox

    BrianCox_01.jpg

    swoon

    Usagi on
  • NeliNeli Registered User regular
    edited February 2010
    Alchemy is gay


    Chemistry is where it's at

    Neli on
    vhgb4m.jpg
    I have stared into Satan's asshole, and it fucking winked at me.
    [/size]
  • PiptheFairPiptheFair Frequently not in boats. Registered User regular
    edited February 2010
    chemistry is something fags do with beakers

    PiptheFair on
  • NeliNeli Registered User regular
    edited February 2010
    beakers are gay

    Fleakers is where it's at

    Neli on
    vhgb4m.jpg
    I have stared into Satan's asshole, and it fucking winked at me.
    [/size]
  • RinderRinder Registered User regular
    edited February 2010
    PiptheFair wrote: »
    science is gay

    alchemy is where it's at

    You get to be pip-squeak.

    Rinder on
  • RabidDeathMooseRabidDeathMoose Registered User regular
    edited February 2010
    PiptheFair wrote: »
    chemistry is something fags do with beakers

    says the chef... :o

    RabidDeathMoose on
  • Peter EbelPeter Ebel CopenhagenRegistered User regular
    edited February 2010
    Chemistry is the art of saying really weird sounds when confronted with a series of balls and sticks or a bunch of lines drawn on a paper.

    Peter Ebel on
    Fuck off and die.
  • BahamutZEROBahamutZERO Registered User regular
    edited February 2010
    I read an interesting article in Scientific American yesterday about a newish theory of quantum gravity that may explain dark matter and dark energy as artifacts of measuring gravity purely relativistically, if it turns out to be accurate.

    It was something like gravity behaves relativistically at lower energies and behaves more Newtonian-style at extremely high energies. Don't ask me to explain, I don't remember more than that.

    BahamutZERO on
    BahamutZERO.gif
  • ButtersButters A glass of some milks Registered User regular
    edited February 2010
    PiptheFair cooks, like a woman. You are a woman, PiptheFair!

    Butters on
    PSN: idontworkhere582 | CFN: idontworkhere | Steam: lordbutters | Amazon Wishlist
  • PiptheFairPiptheFair Frequently not in boats. Registered User regular
    edited February 2010
    oh noooooooooooo

    PiptheFair on
  • BahamutZEROBahamutZERO Registered User regular
    edited February 2010
    and then PiptheFair was the woman

    BahamutZERO on
    BahamutZERO.gif
  • babyeatingjesusbabyeatingjesus Registered User regular
    edited February 2010
    God can we just get a unified field theory done already, science?

    babyeatingjesus on
    hitthatcheeseburgerfatty.gif
  • cadmunkycadmunky One hand on the bottle, The other a shaking fist.Registered User regular
    edited February 2010
    mmmm woman food.

    cadmunky on
    5955603848_aed2690084.jpg
    "Think of it as Evolution in Action"
  • MKRMKR Registered User regular
    edited February 2010
    Makin' gold, crashin' markets

    MKR on
  • HunterHunter Chemist with a heart of Au Registered User regular
    edited February 2010
    PiptheFair wrote: »
    chemistry is something fags do with beakers

    Leave my lab assistant alone.

    lyle_beaker.gif

    Hunter on
  • LanglyLangly Registered User regular
    edited February 2010
    where is Druhim lately

    Langly on
  • PiptheFairPiptheFair Frequently not in boats. Registered User regular
    edited February 2010
    Langly wrote: »
    where is Druhim lately

    became too dessicated

    PiptheFair on
  • UsagiUsagi Nah Registered User regular
    edited February 2010
    PiptheFair wrote: »
    Langly wrote: »
    where is Druhim lately

    became too dessicated

    woops

    Usagi on
  • MKRMKR Registered User regular
    edited February 2010
    Usagi wrote: »
    PiptheFair wrote: »
    Langly wrote: »
    where is Druhim lately

    became too dessicated

    woops

    All your fault.

    MKR on
  • NotASenatorNotASenator Registered User regular
    edited February 2010
    http://www.eso.org/public/images/eso1006a/

    There is a 12640 x 15546px, 341MB version of this image of the Orion Nebula:

    eso1006a.jpg

    NotASenator on
  • cadmunkycadmunky One hand on the bottle, The other a shaking fist.Registered User regular
    edited February 2010
    gorgeous.

    cadmunky on
    5955603848_aed2690084.jpg
    "Think of it as Evolution in Action"
  • ButtersButters A glass of some milks Registered User regular
    edited February 2010
    Langly wrote: »
    where is Druhim lately

    Taking a break after getting jailed over silly goosery.

    Butters on
    PSN: idontworkhere582 | CFN: idontworkhere | Steam: lordbutters | Amazon Wishlist
  • Metzger MeisterMetzger Meister It Gets Worse before it gets any better.Registered User regular
    edited February 2010
    hello science thread.

    Metzger Meister on
  • NotASenatorNotASenator Registered User regular
    edited February 2010
    I downloaded the original size tiff, and this is at 50% zoom:

    orionzoom.jpg

    NotASenator on
  • FishmanFishman Put your goddamned hand in the goddamned Box of Pain. Registered User regular
    edited February 2010
    I feel about that picture the way I used to feel about playboy centerfolds when I was 17.

    Fishman on
    X-Com LP Thread I, II, III, IV, V
    That's unbelievably cool. Your new name is cool guy. Let's have sex.
  • NotASenatorNotASenator Registered User regular
    edited February 2010
    Fishman wrote: »
    I feel about that picture the way I used to feel about playboy centerfolds when I was 17.

    Ambivalence and confusion?

    NotASenator on
  • NotASenatorNotASenator Registered User regular
    edited February 2010
    What is going on here?

    orionzoom2.jpg

    NotASenator on
  • babyeatingjesusbabyeatingjesus Registered User regular
    edited February 2010
    I'll say this right now; if a way becomes available to allow my eyes and brain to perceive full spectrum light and energy I will be first in line because of pictures like that.

    babyeatingjesus on
    hitthatcheeseburgerfatty.gif
  • MKRMKR Registered User regular
    edited February 2010
    It's a star. Remember that if you were in it, you'd never know because the gas is so dispersed. Light comes through just fine.

    MKR on
  • FishmanFishman Put your goddamned hand in the goddamned Box of Pain. Registered User regular
    edited February 2010
    NotACrook wrote: »
    Fishman wrote: »
    I feel about that picture the way I used to feel about playboy centerfolds when I was 17.

    Ambivalence and confusion?

    More illicit and excited, like I'm about to get caught staring at secrets I'm not supposed to know but without actually having the knowledge or experience to truly appreciate or understand the full measure of what I'm looking at.

    Also, totally aroused.

    Fishman on
    X-Com LP Thread I, II, III, IV, V
    That's unbelievably cool. Your new name is cool guy. Let's have sex.
  • babyeatingjesusbabyeatingjesus Registered User regular
    edited February 2010
    Fishman wrote: »
    NotACrook wrote: »
    Fishman wrote: »
    I feel about that picture the way I used to feel about playboy centerfolds when I was 17.

    Ambivalence and confusion?

    More illicit and excited, like I'm about to get caught staring at secrets I'm not supposed to know but without actually having the knowledge or experience to truly appreciate or understand the full measure of what I'm looking at.

    Also, totally aroused.

    I feel guilt now like I did then. I need to confess to someone that I looked at it.

    babyeatingjesus on
    hitthatcheeseburgerfatty.gif
  • FingerSlutFingerSlut __BANNED USERS regular
    edited February 2010
    Someone should add these to master of orion as backdrops. I totally see some gaia planets in there that I need to conquer.

    FingerSlut on
  • RabidDeathMooseRabidDeathMoose Registered User regular
    edited February 2010
    Maybe it's because Hunter posted a shot of his lab assistant on page one but that flare that NAC pointed out looks like a cosmologically sized Beaker.

    RabidDeathMoose on
  • babyeatingjesusbabyeatingjesus Registered User regular
    edited February 2010
    Maybe it's because Hunter posted a shot of his lab assistant on page one but that flare that NAC pointed out looks like a cosmologically sized Beaker.

    Do you mean glassware beaker or muppet Beaker?

    babyeatingjesus on
    hitthatcheeseburgerfatty.gif
  • PiptheFairPiptheFair Frequently not in boats. Registered User regular
    edited February 2010
    Maybe it's because Hunter posted a shot of his lab assistant on page one but that flare that NAC pointed out looks like a cosmologically sized Beaker.

    Do you mean glassware beaker or muppet Beaker?

    yes

    PiptheFair on
  • WeaverWeaver Who are you? What do you want?Registered User regular
    edited February 2010
    NotACrook wrote: »
    What is going on here?

    orionzoom2.jpg


    Magnetar.

    Weaver on
  • FishmanFishman Put your goddamned hand in the goddamned Box of Pain. Registered User regular
    edited February 2010
    So, I just got tickets to Apollo 13:Mission Control.


    Science thread, does anyone know where EECOM is? I want to try for John Aaron.

    Fishman on
    X-Com LP Thread I, II, III, IV, V
    That's unbelievably cool. Your new name is cool guy. Let's have sex.
This discussion has been closed.