Optical counterpart of the east radio lobe of M87
- Autor(en)
- M Stiavelli, J Biretta, Palle Møller, Werner Zeilinger
- Abstrakt
RADIO galaxies are divided into two broad classes1 according to whether they show extended radio lobes ending in hotspots (compact bright sources of radio emission) at some distance from the nucleus (Fanaroff-Riley class II) or instead have bright regions or knots close to the nucleus (FR I). Hotspots and knots emit synchrotron radiation, sometimes even in the optical range2,3. The galaxy M87 (NGC4486) in Virgo is the closest giant elliptical galaxy showing a jet and double-lobe radio structure, and is classified as FR I mainly because of the morphology of the jetdominated west radio lobe, even though the east radio lobe resembles typical FR II objects and shows a hotspot4. We report here the detection of the optical counterpart of this hotspot. Because the lifetime of optically emitting synchrotron electrons is short, we suggest that this hotspot is fed by an unseen counterjet. This conclusion adds weight to the idea that apparently one-sided jet sources are intrinsically two-sided, with the visibility of the receding jet reduced by beaming effects.
- Organisation(en)
- Institut für Astrophysik
- Externe Organisation(en)
- European Southern Observatory (Germany), National Radio Astronomy Observatory Socorro
- Journal
- Nature
- Band
- 355
- Seiten
- 802-804
- Anzahl der Seiten
- 3
- ISSN
- 0028-0836
- Publikationsdatum
- 1992
- Peer-reviewed
- Ja
- ÖFOS 2012
- 103003 Astronomie
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/d732d3f4-1629-4906-887f-270a03608949