• How do you like my orbit determination code?

    I grew dissatisfied with my three-observation method of Gauss program because whenever an asteroid's path across the sky is, during the observation window, a straight line, the equations that find the coefficients for the equations that are recursively solved to find r and rho at time 2 blow up. So I wrote a modified method of Gauss program that... show more
    I grew dissatisfied with my three-observation method of Gauss program because whenever an asteroid's path across the sky is, during the observation window, a straight line, the equations that find the coefficients for the equations that are recursively solved to find r and rho at time 2 blow up. So I wrote a modified method of Gauss program that uses four observations. It doesn't have that problem. It seems to work very well. Find it at https://jenab6.livejournal.com/77958.htm...
    Programming & Design · 3 months ago
  • Do you ever ponder the mass-luminosity relationship for main sequence stars?

    Q = log₁₀ (M/M☉) Mass-Luminosity Relationship. For M/M☉ ≤ 1.0, log(L/L☉) = −3.9428277 Q⁴ − 5.5932802 Q³ + 0.52340218 Q² + 5.04234542 Q + 0.0011365 Mass-Temperature Relationship. For M/M☉ ≤ 1.0, log(T/5777K) = −0.3029217 Q⁴ − 0.1692644 Q³ + 0.54817448 Q² + 0.72509654 Q + 0.00069854 Star's calculated radius from the... show more
    Q = log₁₀ (M/M☉) Mass-Luminosity Relationship. For M/M☉ ≤ 1.0, log(L/L☉) = −3.9428277 Q⁴ − 5.5932802 Q³ + 0.52340218 Q² + 5.04234542 Q + 0.0011365 Mass-Temperature Relationship. For M/M☉ ≤ 1.0, log(T/5777K) = −0.3029217 Q⁴ − 0.1692644 Q³ + 0.54817448 Q² + 0.72509654 Q + 0.00069854 Star's calculated radius from the Stefan-Boltzmann Law. R/R☉ = √(L/L☉) / (T/5777K)²
    1 answer · Astronomy & Space · 1 year ago
  • Absolute magnitudes of brown dwarfs, bolometric and in the J-band?

    QUESTION: Do these curve fits look good? Brown dwarf, J-band (near IR) absolute magnitude versus spectral type. ℳᴊ = 0.00022084027 S⁴ − 0.0659609823 S³ + 7.34624126 S² − 361.274547 S + 6626.69292 where S = 65 for spectral class M5 S = 70 for spectral class L0 S = 80 for spectral class T0 S = 90 for spectral class Y0 Domain... show more
    QUESTION: Do these curve fits look good? Brown dwarf, J-band (near IR) absolute magnitude versus spectral type. ℳᴊ = 0.00022084027 S⁴ − 0.0659609823 S³ + 7.34624126 S² − 361.274547 S + 6626.69292 where S = 65 for spectral class M5 S = 70 for spectral class L0 S = 80 for spectral class T0 S = 90 for spectral class Y0 Domain Restricted: S = 65 to 92. Estimated bolometric correction for brown dwarf J band absolute magnitudes. BCᴊ = −0.00032222 T + 2.9212 where T is the effective temperature. L0 brown dwarf has bolometric absolute magnitude of +9.54 (this probably should be one magnitude dimmer) Y2 brown dwarf has bolometric absolute magnitude of +23.08 (this is about right)
    1 answer · Astronomy & Space · 1 year ago
  • What is "non-gravitational astrodynamics"?

    Astrodynamics is the study and prediction of motion in a gravity-dominated physical system. Astrodynamics is, as far as I know, never such that it has nothing to do with gravity. And yet at least one member of the faculty at the University of Texas at Austin specializes in something called "non-gravitational astrodynamics." I'd... show more
    Astrodynamics is the study and prediction of motion in a gravity-dominated physical system. Astrodynamics is, as far as I know, never such that it has nothing to do with gravity. And yet at least one member of the faculty at the University of Texas at Austin specializes in something called "non-gravitational astrodynamics." I'd never heard of it before. What's it all about? Might I have some example homework problems in that subject?
    5 answers · Astronomy & Space · 1 year ago
  • Are Nagler telescope eyepieces worth what they cost?

    What kind of view does a thousand-dollar eyepiece give you, that you'd be willing to pay so much cash for it?
    What kind of view does a thousand-dollar eyepiece give you, that you'd be willing to pay so much cash for it?
    1 answer · Astronomy & Space · 1 year ago
  • Why will these aliens not send any ships to the Milky Way Galaxy?

    Alien astronomers in another galaxy observe the Milky Way. By its redshift, they calculate its distance as 7.94 billion light years. Someone proposes that intergalactic colony ships be sent to the Milky Way to seed it with their kind. But the experts refuse, saying that there's no point to it. What is the expert aliens' reason?
    Alien astronomers in another galaxy observe the Milky Way. By its redshift, they calculate its distance as 7.94 billion light years. Someone proposes that intergalactic colony ships be sent to the Milky Way to seed it with their kind. But the experts refuse, saying that there's no point to it. What is the expert aliens' reason?
    5 answers · Astronomy & Space · 1 year ago
  • How about that Red Spot? Big, huh? Swirly too?

    Juno photographed it shortly after perijove on 10 July 2017. https://www.missionjuno.swri.edu/Vault/V... (I was watching the simulation the whole time on Youtube, calling out the Jovicentric distances and the true anomalies on the chat.)
    Juno photographed it shortly after perijove on 10 July 2017. https://www.missionjuno.swri.edu/Vault/V... (I was watching the simulation the whole time on Youtube, calling out the Jovicentric distances and the true anomalies on the chat.)
    2 answers · Software · 1 year ago
  • Detailed luminosity function. Do these number densities for stars look accurate?

    In a typical spherical volume in the solar neighborhood, having a radius of 562 light years, there will be about... • 1 main sequence star of spectral type O. 1.345e-9 main sequence O stars per cubic light year. • 3400 main sequence stars of spectral type B. 4.573e-6 main sequence B stars per cubic light year. • 17000 main sequence stars of... show more
    In a typical spherical volume in the solar neighborhood, having a radius of 562 light years, there will be about... • 1 main sequence star of spectral type O. 1.345e-9 main sequence O stars per cubic light year. • 3400 main sequence stars of spectral type B. 4.573e-6 main sequence B stars per cubic light year. • 17000 main sequence stars of spectral type A. 2.286e-5 main sequence A stars per cubic light year. • 82000 main sequence stars of spectral type F. 1.103e-4 main sequence F stars per cubic light year. • 204000 main sequence stars of spectral type G. 2.744e-4 main sequence G stars per cubic light year. • 325000 main sequence stars of spectral type K. 4.371e-4 main sequence K stars per cubic light year. • 2100000 main sequence stars of spectral type M. 0.002824 main sequence M stars per cubic light year. • 800000 brown dwarfs of types L, T, and Y. 0.001076 brown dwarfs per cubic light year. • 110000 white dwarfs. 1.479e-4 white dwarfs per cubic light year. • 38000 subgiant stars. 5.111e-5 subgiants per cubic light year. • 6000 giant stars 8.070e-6 giant stars per cubic light year. • 1 supergiant star 1.345e-9 supergiant stars per cubic light year.
    1 answer · Astronomy & Space · 1 year ago
  • Detailed luminosity function. Do these number densities for stars look accurate?

    In a typical spherical volume in the solar neighborhood, having a radius of 562 light years, there will be about... • 1 main sequence star of spectral type O. 1.345e-9 main sequence O stars per cubic light year. • 3400 main sequence stars of spectral type B. 4.573e-6 main sequence B stars per cubic light year. • 17000 main sequence stars of... show more
    In a typical spherical volume in the solar neighborhood, having a radius of 562 light years, there will be about... • 1 main sequence star of spectral type O. 1.345e-9 main sequence O stars per cubic light year. • 3400 main sequence stars of spectral type B. 4.573e-6 main sequence B stars per cubic light year. • 17000 main sequence stars of spectral type A. 2.286e-5 main sequence A stars per cubic light year. • 82000 main sequence stars of spectral type F. 1.103e-4 main sequence F stars per cubic light year. • 204000 main sequence stars of spectral type G. 2.744e-4 main sequence G stars per cubic light year. • 325000 main sequence stars of spectral type K. 4.371e-4 main sequence K stars per cubic light year. • 2100000 main sequence stars of spectral type M. 0.002824 main sequence M stars per cubic light year. • 800000 brown dwarfs of types L, T, and Y. 0.001076 brown dwarfs per cubic light year. • 110000 white dwarfs. 1.479e-4 white dwarfs per cubic light year. • 38000 subgiant stars. 5.111e-5 subgiants per cubic light year. • 6000 giant stars 8.070e-6 giant stars per cubic light year. • 1 supergiant star 1.345e-9 supergiant stars per cubic light year.
    Physics · 1 year ago
  • Does quantization of space preclude the existence of singularities?

    If there can be no separation smaller than the Planck length, then there exists also a minimum radius of curvature for space. There can be no infinite curvature of space because there can be no infinitesimal radius for that curvature.
    If there can be no separation smaller than the Planck length, then there exists also a minimum radius of curvature for space. There can be no infinite curvature of space because there can be no infinitesimal radius for that curvature.
    4 answers · Physics · 1 year ago
  • Why colonize space and/or other planets?

    This is the sort of question that always precedes a colonization effort, which never occurs to anyone after the effort has borne fruit. That is, before colonization happens, the least visionary of men question the value of the endeavor, whereas after the colonies are established the very question seems rather stupid. I think that the value of... show more
    This is the sort of question that always precedes a colonization effort, which never occurs to anyone after the effort has borne fruit. That is, before colonization happens, the least visionary of men question the value of the endeavor, whereas after the colonies are established the very question seems rather stupid. I think that the value of planting "people gardens," all by itself, constitutes a sufficient reason for space colonization. Subsequent benefits like science, technological spinoffs, cultural innovations, and interplanetary trade are extras.
    5 answers · Astronomy & Space · 1 year ago
  • Why does honeywheat bread taste like cake made from sawdust instead of flour?

    Powder sawdust, with sugar added, of course.
    Powder sawdust, with sugar added, of course.
    1 answer · Military · 1 year ago
  • Why does honeywheat bread taste like cake made from sawdust instead of flour?

    Powder sawdust, with sugar added, of course.
    Powder sawdust, with sugar added, of course.
    3 answers · Vegetarian & Vegan · 1 year ago
  • What goes in the blank?

    Fred Flintstone killed a Saber-Tooth on Monday. Joe Gentile killed a _______ on Tuesday. George Jetson killed an Alien on Wednesday.
    Fred Flintstone killed a Saber-Tooth on Monday. Joe Gentile killed a _______ on Tuesday. George Jetson killed an Alien on Wednesday.
    2 answers · Comics & Animation · 1 year ago
  • Do you think the US Government will commemorate the 50th Anniversary of the USS Liberty Incident?

    They do have a few hours left to do it in, provided that they hold the memorial ceremony after close-of-business. http://www.gtr5.com/
    They do have a few hours left to do it in, provided that they hold the memorial ceremony after close-of-business. http://www.gtr5.com/
    1 answer · Other - Politics & Government · 1 year ago
  • Do you think the US Government will commemorate the 50th Anniversary of the USS Liberty Incident?

    They do have a few hours left to do it in, provided that they hold the memorial ceremony after close-of-business. http://www.gtr5.com/
    They do have a few hours left to do it in, provided that they hold the memorial ceremony after close-of-business. http://www.gtr5.com/
    Government · 1 year ago
  • Do you think the US Government will commemorate the 50th Anniversary of the USS Liberty Incident?

    They do have a few hours left to do it in, provided that they hold the memorial ceremony after close-of-business. http://www.gtr5.com/
    They do have a few hours left to do it in, provided that they hold the memorial ceremony after close-of-business. http://www.gtr5.com/
    1 answer · Politics · 1 year ago
  • What happens when the radius for the curvature of spacetime becomes less than the Planck length?

    Quantum and relativity unifiers, start your engines.
    Quantum and relativity unifiers, start your engines.
    3 answers · Physics · 1 year ago