Motivation and Data Source

• Big Data and Astronomy go hand in hand

• Sloan Digital Sky Survey

• SQL Based Search

Goals

• Map the Universe

• Visualize the relationship between temperature and magnitude (brightness)

• Create a custom classification system

Initial Steps

• Extensive Tidying and Trimming

Custom Classification

stars$shane_class <- NA
stars <- stars  %>% 
  relocate(shane_class, .after = subclass)
summary(stars$temp)

##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##    4016    5590    6018    6191    6891    8932

for (idx in 1:nrow(stars)){
  if (stars[idx, ]$temp >= 4000 && stars[idx, ]$temp < 5000){
    stars[idx, ]$shane_class <- 'canadian'
  }
  if (stars[idx, ]$temp >= 5000 && stars[idx, ]$temp < 5750){
    stars[idx, ]$shane_class <- 'chilly'
  }
  if (stars[idx, ]$temp >= 5750 && stars[idx, ]$temp < 6250){
    stars[idx, ]$shane_class <- 'sunny'
  }
  if (stars[idx, ]$temp >= 6250 && stars[idx, ]$temp < 7000){
    stars[idx, ]$shane_class <- 'tropical'
  }
  if (stars[idx, ]$temp >= 7000 && stars[idx, ]$temp < 8000){
    stars[idx, ]$shane_class <- 'equatorial'
  }
  if (stars[idx, ]$temp >= 8000 && stars[idx, ]$temp < 9000){
    stars[idx, ]$shane_class <- 'deadly'
  }
}

Distribution of Custom Classes

Temperature and Magnitude

## `geom_smooth()` using method = 'gam' and formula 'y ~ s(x, bs = "cs")'

## `geom_smooth()` using formula 'y ~ x'

Regression Analysis

Temperature-Magnitude Diagram with better dataset

## Warning: Removed 59 rows containing missing values (geom_point).

Universally Accepted Hertzprung-Russell Diagram

HR-Diagram

Mapping the Universe

2-D Cartesian

2-D Polar

3-D With Uniform Radius

3-D With R = Observed Redshift

References

Dincer, Baris. “Star Type Classification / NASA.” Kaggle, 2 Apr. 2021, https://www.kaggle.com/brsdincer/star-type-classification.

Information@eso.org. “Hertzsprung-Russell Diagram.” Www.eso.org, https://www.eso.org/public/images/eso0728c/.

“List of Common Coordinate Transformations.” Wikipedia, Wikimedia Foundation, 17 Mar. 2021, https://en.wikipedia.org/wiki/List_of_common_coordinate_transformations#From_polar_coordinates. “Measures of Flux and Magnitude.” SDSS, https://www.sdss.org/dr12/algorithms/magnitudes/#mag_psf.

“Modified Julian Date – from Eric Weisstein’s World of Astronomy.” Scienceworld.wolfram.com, https://scienceworld.wolfram.com/astronomy/ModifiedJulianDate.html.

SDSS Filters, https://skyserver.sdss.org/dr1/en/proj/advanced/color/sdssfilters.asp.

SDSS SkyServer DR16, http://skyserver.sdss.org/dr16/en/tools/search/sql.aspx.

“SEGUE: Mapping The Outer Milky Way.” SDSS, https://www.sdss.org/surveys/segue/.

“SEGUE Stellar Target Selection: Detailed Selection Criteria.” SDSS, https://www.sdss.org/dr12/algorithms/segue_target_selection_details/#kd.

Smith, J. Allyn, et al. (2007). The ugriz Standard-Star System. The Astronomical Journal, 123(4). https://doi.org/10.1086/339311

“What Is the Sloan Digital Sky Survey?” SkyServer, http://skyserver.sdss.org/dr7/en/sdss/.

SkyServer

SQL Search Engine for SDSS Data:

http://skyserver.sdss.org/dr16/en/tools/search/sql.aspx