Open main menu
Home
Random
Recent changes
Special pages
Community portal
Preferences
About Wikipedia
Disclaimers
Incubator escapee wiki
Search
User menu
Talk
Dark mode
Contributions
Create account
Log in
Editing
Parsec
(section)
Warning:
You are not logged in. Your IP address will be publicly visible if you make any edits. If you
log in
or
create an account
, your edits will be attributed to your username, along with other benefits.
Anti-spam check. Do
not
fill this in!
=== Parsecs and kiloparsecs === Distances expressed in parsecs (pc) include distances between nearby stars, such as those in the same [[spiral arm]] or [[globular cluster]]. A distance of {{Convert|1000|pc|ly|sigfig=4}} is denoted by the kiloparsec (kpc). Astronomers typically use kiloparsecs to express distances between parts of a [[galaxy]] or within [[galaxy group|groups of galaxies]].<ref>{{Cite web |author1=Andrew May |date=2022-07-29 |title=What is a parsec? Definition and calculation |url=https://www.space.com/parsec |access-date=2025-01-16 |website=Space.com |language=en}}</ref> So, for example: * [[Proxima Centauri]], the nearest known star to Earth other than the Sun, is about {{Convert|1.3|pc|ly|sigfig=3}} away by direct parallax measurement.<ref>{{Cite web |title=How Do We Know How Far Away the Stars Are? |url=https://www.britannica.com/story/how-do-we-know-how-far-away-the-stars-are#:~:text=The%20closest%20star,%20Proxima%20Centauri,would%20take%20950%20million%20years. |access-date=2025-01-16 |website=www.britannica.com |language=en}}</ref> * The distance to the [[open cluster]] [[Pleiades]] is {{Val|130|10|u=pc}} ({{Val|420|30|u=ly}}) from us per ''[[Hipparcos]]'' parallax measurement.<ref>{{Cite web |title=The Pleiades Star Cluster {{!}} Royal Observatory Greenwich Astronomy Guides |url=https://www.rmg.co.uk/stories/topics/what-are-pleiades#:~:text=The%20Pleiades%20(pronounced%20'Ply-,light%20years%20away%20from%20Earth. |access-date=2025-01-16 |website=www.rmg.co.uk |language=en}}</ref> * The [[Galactic Center|centre]] of the [[Milky Way]] is more than {{Convert|8|kpc|ly}} from the Earth and the Milky Way is roughly {{Convert|34|kpc|ly}} across.<ref>{{Cite web |date=2018-01-10 |title=Scientists Take Viewers to the Center of the Milky Way - NASA |url=https://www.nasa.gov/universe/scientists-take-viewers-to-the-center-of-the-milky-way/#:~:text=The%20Earth%20is%20located%20about,the%20center%20of%20the%20Galaxy. |access-date=2025-01-16 |language=en-US}}</ref> * [[ESO 383-76]], one of the [[List of largest galaxies|largest known galaxies]], has a diameter of {{Convert|540.9|kpc|e6ly|1|abbr=unit}}.<ref>{{Cite web |date=18 September 2022 |title=Eso 383-76 Galaxy Facts, Distance & Size |url=https://www.universeguide.com/galaxy/eso-383-76 |access-date=2025-01-16 |website=Universe Guide |language=en-us}}</ref> * The [[Andromeda Galaxy]] ([[Messier object|M31]]) is about {{Convert|780|kpc|e6ly|abbr=unit}} away from the Earth.<ref>{{Cite web |title=The Galaxy Next Door |url=https://www.nasa.gov/image-article/galaxy-next-door/#:~:text=At%20approximately%202.5%20million%20light,spans%20260,000%20light-years%20across. |access-date=2025-01-16 |language=en-US}}</ref>
Edit summary
(Briefly describe your changes)
By publishing changes, you agree to the
Terms of Use
, and you irrevocably agree to release your contribution under the
CC BY-SA 4.0 License
and the
GFDL
. You agree that a hyperlink or URL is sufficient attribution under the Creative Commons license.
Cancel
Editing help
(opens in new window)