The Helix Nebula: a Gaseous Envelope Expelled By a Dying Star

 The Helix Nebula: a Gaseous Envelope Expelled By a Dying Star

This composite image is a view of the colorful Helix Nebula taken with the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope and the Mosaic II Camera on the 4-meter telescope at Cerro Tololo Inter-American Observatory in Chile. The object is so large that both telescopes were needed to capture a complete view. The Helix is a planetary nebula, the glowing gaseous envelope expelled by a dying, sun-like star. The Helix resembles a simple doughnut as seen from Earth. But looks can be deceiving. New evidence suggests that the Helix consists of two gaseous disks nearly perpendicular to each other.

One possible scenario for the Helix's complex structure is that the dying star has a companion star. One disk may be perpendicular to the dying star's spin axis, while the other may lie in the orbital plane of the two stars. The Helix, located 690 light-years away, is one of the closest planetary nebulas to Earth.

The Hubble images were taken on November 19, 2002; the Cerro Tololo images on Sept. 17-18, 2003.

Credits

NASA, ESA, C.R. O'Dell (Vanderbilt University), M. Meixner and P. McCullough (STScI)

About The Object
Object Name Helix Nebula, NGC 7293
Object Description Planetary Nebula
R.A. Position 22h 29m 48.19s
Dec. Position -20° 49' 25.99"
Constellation Aquarius
Distance About 690 light-years (213 parsecs)
Dimensions The image is roughly 287 arcminutes (5.6 light-years or 1.7 parsecs) across.
About The Data
Data Description The HST data are from proposal . Processed images may be obtained from the Helix MAST web site. The Hubble Helix Team includes: M. Meixner, H.E. Bond, G. Chapman (STScI), Y.-H. Chu (U. Illinois, Urbana-Champaign), P. Cox (Institut d'Astrophysique Spatiale, France), W. Crothers, L.M. Frattare, R.Gilliland (STScI), M. Guerrero R. Gruendl (U. Illinois, Urbana-Champaign), F. Hamilton, (STScI), R.Hook (STScI/ESO), P. Huggins (New York Univ.), I. Jordan, C.D. Keyes, A. Koekemoer (STScI), K.Kwitter (Williams College), Z.G. Levay, P.R. McCullough, M. Mutchler, K. Noll (STScI), C.R. O'Dell (Vanderbilt University), N. Panagia, M. Reinhart, M. Robberto, K. Sahu, D. Soderblom, L. Stanghellini, C. Tyler, J. Valenti, A. Welty, R. Williams (STScI). The CTIO data were taken by C.R. O'Dell (Vanderbilt University) and L.M. Frattare (STScI). The science team includes C.R. O'Dell (Vanderbilt University), P.R. McCullough and M. Meixner (STScI).
Instrument HST>ACS and CTIO>Mosaic II
Exposure Dates November 19, 2002, Exposure Time: 4.5 hours (ACS); September 17-18, 2003, Exposure Time: 10 minutes (Mosaic II)
Filters ACS: F502N ([O III]) and F658N (H-alpha) Mosaic II: c6009 (H-alpha) and kc6014 ([O III])
About The Image
Color Info Blue: F502N ([O III]) Green: c6009 (H-alpha) and kc6014 ([O III]) Red: F658N (H-alpha)
Compass Image The Helix Nebula: a Gaseous Envelope Expelled By a Dying Star
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.