Sökning: "Hipparcos"

Visar resultat 1 - 5 av 8 uppsatser innehållade ordet Hipparcos.

  1. 1. Combining Hipparcos and Gaia data: Improved Astrometric Calculations With Orvara

    Kandidat-uppsats, Lunds universitet/Astrofysik; Lunds universitet/Fysiska institutionen

    Författare :Melvin Tham; [2023]
    Nyckelord :Astrometry; Af Leporis; Smethells 119; Gliese 105; Gliese 86; Orvara; Hipparcos; Gaia; Physics and Astronomy;

    Sammanfattning : Hipparcos and Gaia are two missions intended to catalogue positions and motions of stellar objects. Orvara is a computer program which aims to combine the data from these two missions to calculate Keplerian parameters for stellar systems. LÄS MER

  3. 2. Re-examining the dynamics of the Milky Way with new distance estimates

    Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

    Författare :John Wimarsson; [2018]
    Nyckelord :Milky Way dynamics; Gaia; distance estimates; Physics and Astronomy;

    Sammanfattning : The use of reliable distance estimates is key to derive accurate three-dimensional velocities of celestial objects. Systematic overestimation and large uncertainties in the distances will thus provide misleading information of an object's kinematics. LÄS MER

  4. 3. Assessing the Improvements GAIA-DR1 Will Bring to Dynamical Astronomy

    Kandidat-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation

    Författare :Mateo Prgomet; [2017]
    Nyckelord :Physics and Astronomy;

    Sammanfattning : The first part of this thesis deals with the dynamical estimation of the Oort constants using proper motions and parallaxes provided from the Gaia-DR1 TGAS catalogue. The photometric information was provided by the 2MASS catalogue. LÄS MER

  5. 4. Radial migration of stars, measured in N-body simulations

    Master-uppsats, Lunds universitet/Astronomi - Genomgår omorganisation; Lunds universitet/Institutionen för astronomi och teoretisk fysik - Genomgår omorganisation

    Författare :Daniel Mikkola; [2017]
    Nyckelord :N-body; simulations; galaxies; radial migration; stars; Physics and Astronomy;

    Sammanfattning : The purpose of Galactic archaeology is determining the history of the Milky Way (MW) Galaxy. To do this one uses observational data from stellar populations in terms of properties such as kinematics, chemistry, ages, and evolution. LÄS MER

  7. 5. A kinematic check of the distance scale of Galactic Cepheids

    Kandidat-uppsats, Lunds universitet/Institutionen för astronomi och teoretisk fysik - Genomgår omorganisation; Lunds universitet/Astronomi - Genomgår omorganisation

    Författare :Brian Thorsbro; [2014]
    Nyckelord :cepheid; period-luminosity relation; distance scale; kinematics; Physics and Astronomy;

    Sammanfattning : A selection of well known period luminosity relations for cepheid variables are studied under the assumption that cepheid variables have a mean vertical velocity of zero in the galactic plane. Proper motion data from Hipparcos and Thyco-2 catalogues are coupled with the distances obtained from applying the period luminosity relations on a database of known classical cepheids to calculate the velocities of the cepheids. LÄS MER