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Available downloads

For those who prefer working with plain files we offer several such files for a direct download:

  • A complete set of rectangular coordinates and velocity components of all 155 considered potential perturbers in a heliocentric, Galactic reference frame, additionally with a total perturber mass in the last column. For a detailed description on how these positions and velocity were obtained see our paper: 2015MNRAS.449.2459D. In the first two columns we included our internal code of the perturber and its name.
    • Download the above mentioned file here.
  • A complete list of Sun — star (or stellar system) nominal encounter parameters for all 155 considered objects. This is a result of a numerical integration of ALL these objects and the Sun SIMULTANEOUSLY, taking into account all gravitational mutual interactions and the Galactic overall potential. This calculation was performed in a Galactocentric frame and details are also available in the above mentioned paper. In each row we present: the minimal distance between the Sun and a perturber, an epoch of the encounter (negative for past events), a relative velocity during an encounter and a mass of the perturber. In the first two columns we include our internal code of the perturber and its name. The whole file is sorted by a minimal distance.
    • Download this file here
  • The third file available for download is a complete dump of all input data for all 158 individual objects in the database, i.e. positions, proper motions, radial velocities, parallaxes as well as the mass and heliocentric distance estimations. This set consists of 142 single stars, 12 components of multiple objects and 4 components that are currently treated as single stars due to the lack or incomplete data for the rest of the multiple system. For all values both uncertainties (where available) and sources are also included. For components of P0403, P1037, and P1069 there are no input data in our database since the systemic Galactic position and velocity components, as well as their total masses, were taken directly from the literature.
    • Download this file here
  • Starting with the StePPeD release 3.2 we also include full geometry, statistics and uncertainties description of the close stellar passages near the Sun obtained with the Monte Carlo method. These results are also prepared in a form of the plain ASCII file available here for download. According to the Gaia EDR3 covariance matrices we draw more than 10 000 clones of each perturber and analyzed the cloud of this clones stopped at their closest proximity to the Sun. This procedure cannot be applied for P0403, P0404, P1006, P1007, P1019, P1037 i P1069 due to their absence in Gaia EDR3.
    In the file available below we present the description of the clone cloud geometry by means of the distance between the cloud centroid and the Sun and by two values of the sphere radius around this centroid (r68 and r90) in 68% or 90% of clones can be found respectively. These values are in columns 4 - 6. First three columns contain our internal perturber code, its name and the number of clones used in the simulation.
    The rest of each row consist of the three groups of five columns each, describing statistically three sets of clone set parameters: distances from the Sun, time of the closest approach and a relative velocity. In each group we present five values: mean, standard deviation, median, two percentiles p16 and p84, and the value of the Anderson-Darling test for normality a2. If a2 < 0.8 the Gaussian distribution parameters (mean and can be used, otherwise (including cases where a2 is negative) we recommend the mean and two percentiles .
    • Download this file here

Based on the StePPeD 3.2 release we prepared a new set of numerical ephemerides providing Galactocentric positions of all potential stellar perturbers and the Sun for the past and future 30 Myr. These ephemerides can be used as the source of perturbing bodies positions for numerical studies of a long term motion of Solar System small bodies in all cases when the Galactic and stellar perturbations should be taken into account, for example in long-period comet source and origin studies. The detailed description of these ephemerides construction and the way of their effective usage can be found in a paper by Dybczyński & Breiter (A&A, Volume 657, id.A65, 2022A&A...657A..65D).