How accurate is the distance to M4 and its stars according to different sources?

In summary, there are contradictory numbers for the distance to M4, with sources citing distances of 7200 ly, 3800 pc, and 5500 ly. The precision of Gaia in measuring radial distances and peculiar motions of stars in M4 is uncertain, and it is unclear what kinds of orbits stars in the outskirts of M4 follow. It is also unclear if Gaia has the precision to measure peculiar accelerations of stars in globular clusters.
  • #1
snorkack
2,190
477
How far is M4? I have seen contradictory numbers for M4 and stars in it.
How precise is Gaia in measuring the radial distances to various stars in M4? Their radial position relative to each other? Their peculiar motions?
What kinds of orbits do stars in the outskirts of M4 follow? High eccentricity orbits that bring them to cluster interior on each periapse, or low eccentricity orbits that stay on the outskirts of cluster all along?
Does Gaia have the precision to measure peculiar accelerations of stars in globular clusters?
 
Astronomy news on Phys.org
  • #2
snorkack said:
I have seen contradictory numbers for M4 and stars in it.
Where?
 
  • Like
Likes Vanadium 50
  • #3
malawi_glenn said:
Where?
This:
https://en.wikipedia.org/wiki/Messier_4
offers 7200 ly, (2200 pc) with reference to
https://ui.adsabs.harvard.edu/abs/1985A&A...143...8C
But it also claims PSR B1620−26 as a member (rather than a background object), reference to https://esahubble.org/images/potw1236a/
This:
https://en.wikipedia.org/wiki/PSR_B1620−26
claims the distance to PSR B1620−26 as 3800 pc (12 400 ly), source:
http://exoplanet.eu/catalog/psr_b1620-26_(ab)_b/
This:
https://www.eso.org/public/images/m4/
quotes 5500 ly
5500 ly and 12400 ly is a gross difference. Does Gaia have any comment?
 

1. How is the distance to M4 and its stars measured?

The distance to M4 and its stars is measured using a method called parallax. This involves measuring the apparent shift in position of the stars as the Earth orbits around the Sun. The greater the shift, the closer the star is to Earth. This method is used by various sources to determine the distance to M4 and its stars.

2. Why do different sources report different distances to M4 and its stars?

Different sources may report different distances to M4 and its stars due to variations in the methods and data used for measurement. Some sources may use more accurate equipment or techniques, while others may have outdated data or use different assumptions in their calculations.

3. Which source is considered to have the most accurate distance measurement to M4 and its stars?

The most accurate source for the distance to M4 and its stars is currently the European Space Agency's Gaia mission. This mission uses advanced instruments and techniques to measure the distances to over a billion stars, including those in M4. Its measurements have been found to be highly accurate and have significantly improved our understanding of the distance to M4 and its stars.

4. How does the accuracy of the distance to M4 and its stars impact our understanding of the cluster?

The accuracy of the distance to M4 and its stars is crucial in determining the cluster's size, age, and composition. By knowing the precise distance, we can more accurately measure the cluster's size and determine its position in the galaxy. This information also helps us understand the cluster's evolution and composition, which in turn contributes to our understanding of the formation and evolution of galaxies.

5. Are there ongoing efforts to improve the accuracy of the distance to M4 and its stars?

Yes, there are ongoing efforts to improve the accuracy of the distance to M4 and its stars. The Gaia mission continues to gather data and improve its measurements, and other ground-based and space-based missions are also working to refine our understanding of the distances to stars in M4 and other clusters. As technology and techniques advance, we can expect even more precise measurements in the future.

Similar threads

Are Distant Globular Clusters the Key to Testing Newtonian Gravity?
    • Cosmology
Replies
19
Views
3K
How Do Astronomers Determine the Distance to a Star Cluster?
    • Introductory Physics Homework Help
Replies
1
Views
3K
Starring Gravity, Co-Starring Magnetism
    • Astronomy and Astrophysics
Replies
7
Views
3K
Kerbal Space Program - Rocket Design Basics
    • Aerospace Engineering
Replies
2
Views
7K
I Exploring ΛCDM Model: Cosmology Intertwined in 4 Pre-Prints
    • Cosmology
Replies
1
Views
1K
Big Bang Big Schmang, astronomical redshift is an artifact of distance
    • Cosmology
Replies
1
Views
2K
Universal Structure - Bubble Theory
    • Beyond the Standard Models
Replies
2
Views
11K
Possibly solved the metric without field equations
    • Special and General Relativity
Replies
11
Views
2K
Questions on Redshift, Hubble’s Law, spacetime expansion and the standard model
    • Cosmology
Replies
21
Views
3K
Equivalence of the 'expanding space' & 'kinematic' paradigms
    • Cosmology
Replies
3
Views
2K

Hot Threads

Recent Insights

Back
Top