White Dwarf Stars in the Milky Way Bulge

 White Dwarf Stars in the Milky Way Bulge

NASA's Hubble Space Telescope has detected for the first time a population of white dwarfs embedded in the hub of our Milky Way galaxy. The Hubble images are the deepest, most detailed study of the galaxy's central bulge of stars. The smoldering remnants of once-vibrant stars can yield clues to our galaxy's early construction stages that happened long before Earth and our sun formed.

[Left] – This is a ground-based view of the Milky Way's central bulge, seen in the direction of the constellation Sagittarius. Giant dust clouds block most of the starlight coming from the galactic center. Hubble, however, peered through a region (marked by the arrow) called the Sagittarius Window, which offers a keyhole view into the galaxy's hub.

[Upper right] – This is a small section of Hubble's view of the dense collection of stars crammed together in the galactic bulge. The region surveyed is part of the Sagittarius Window Eclipsing Extrasolar Planet Search (SWEEPS) field and is located 26,000 light-years away.

[Lower right] – Hubble uncovered extremely faint and hot white dwarfs. This is a sample of 4 out of the 70 brightest white dwarfs spied by Hubble in the Milky Way's bulge. Astronomers picked them out based on their faintness, blue-white color, and motion relative to our sun. The numbers in the inset images correspond to the white dwarfs' location in the larger Hubble view.

Hubble's Advanced Camera for Surveys made the observations in 2004 and 2011-2013.

Credits

Hubble Images: NASA, ESA, A. Calamida and K. Sahu (STScI), and the SWEEPS Science Team;
Ground-based Image: A. Fujii

About The Object
Object Name SWEEPS Field
Object Description Stellar Survey Field Near the Galactic Bulge
R.A. Position 17h 59m 01.89s
Dec. Position -29° 13' 40.69"
Constellation Sagittarius
About The Object
Object Name A name or catalog number that astronomers use to identify an astronomical object.
Object Description The type of astronomical object.
R.A. Position Right ascension – analogous to longitude – is one component of an object's position.
Dec. Position Declination – analogous to latitude – is one component of an object's position.
Constellation One of 88 recognized regions of the celestial sphere in which the object appears.
Distance The physical distance from Earth to the astronomical object. Distances within our solar system are usually measured in Astronomical Units (AU). Distances between stars are usually measured in light-years. Interstellar distances can also be measured in parsecs.
Dimensions The physical size of the object or the apparent angle it subtends on the sky.
About The Data
Data Description
  • Proposal: A description of the observations, their scientific justification, and the links to the data available in the science archive.
  • Science Team: The astronomers who planned the observations and analyzed the data. "PI" refers to the Principal Investigator.
Instrument The science instrument used to produce the data.
Exposure Dates The date(s) that the telescope made its observations and the total exposure time.
Filters The camera filters that were used in the science observations.
About The Image
Image Credit The primary individuals and institutions responsible for the content.
Publication Date The date and time the release content became public.
Color Info A brief description of the methods used to convert telescope data into the color image being presented.
Orientation The rotation of the image on the sky with respect to the north pole of the celestial sphere.