The teeming stars of the globular cluster
NGC 6544 glisten in this image from the NASA/ESA Hubble Space
Telescope. This cluster of tightly bound stars lies more than 8000
light-years away from Earth and is — like all globular clusters — a
densely populated region of tens of thousands of stars.
This image of NGC 6544 combines data from two of Hubble’s instruments — the Advanced Camera for Surveys and Wide Field Camera 3
— as well as two separate astronomical observations. The first
observation was designed to find a visible counterpart to the radio
pulsar discovered in NGC 6544. A pulsar is the rapidly spinning remnant
of a dead star,
emitting twin beams of electromagnetic radiation like a vast
astronomical lighthouse. This pulsar rotates particularly quickly, and
astronomers turned to Hubble to help determine how this object evolved
in NGC 6544.
The second observation which contributed data to this image was also
designed to find the visible counterparts of objects detected at other electromagnetic wavelengths.
Instead of matching up sources to a pulsar, however, astronomers used
Hubble to search for the counterparts of faint X-ray sources. Their
observations could help explain how clusters like NGC 6544 change over
time.
NGC 6544 lies in the constellation Sagittarius, close to the vast Lagoon Nebula, a hazy labyrinth of gas and dust
sculpted by the fierce winds of newly born stars. The Lagoon Nebula is
truly colossal — even by astronomical standards — and measures 55
light-years across and 20 light-years from top to bottom. Previous Hubble images of the nebula incorporated infrared
observations to reveal young stars and intricate structures that would
be obscured at visible wavelengths by clouds of gas and dust.
Friday, June 23, 2023
On the edge of the Lagoon On the edge of the Lagoon
A cluster of stars in warm and cool
colours. The whole view is filled with small stars, which become much
denser and brighter around a core just right of centre. Most of the
stars are small, but some are larger with a round, brightly-coloured
glow and four sharp diffraction spikes. Behind the stars, a dark
background can be seen
