The Fornax Dwarf is the most luminous of the Milky Way’s dwarf spheroidal galaxies, a satellite with its own globular clusters orbiting inside it.
At a glance
| type | galaxy |
|---|---|
| distance from the Sun | 457,000 light-years (140 kpc) |
| its light left it | 457,000 years ago |
| size in the piece | about 2,400 light-years acrossmodel |
Read off the piece’s own catalogue, the same values it draws with. Model marks a property of the piece’s galaxy model rather than a measurement.
About Fornax Dwarf
Harlow Shapley found the Fornax Dwarf soon after Sculptor, on plates taken in South Africa. It lies in the southern constellation Fornax and is the brightest and most massive of the classical dwarf spheroidal satellites. Unlike Sculptor, it kept forming stars for much of its history, so it holds a mix of ancient and much younger populations.
It is unusual in having its own system of globular clusters, one of them bright enough to have been found before the galaxy itself. Their survival is a puzzle: in a galaxy whose mass is concentrated at the centre, friction with the dark matter should have dragged them inward long ago. That has made Fornax a key case in the debate over whether dwarf galaxies have dense dark matter cusps or flat cores.
What you see in the piece
In the piece it is a diffuse swarm of warm-coloured stars far below the disc, the richest of the Milky Way’s spheroidal satellites, invisible from the Sun.
Measured or modelled
Whether its globular clusters survive because its dark matter has a flat core, or because of their orbits, is debated.
Questions
Does the Fornax Dwarf galaxy have globular clusters?
Yes, it has its own family of globular clusters, which is unusual for a dwarf galaxy and puzzling because they should have sunk to its centre.
How far away is the Fornax Dwarf?
The Fornax Dwarf is 457,000 light-years (140 kpc) from the Sun, so its light left it 457,000 years ago.