Talk:Stellar kinematics

Wiki Education Foundation-supported course assignment

This article is or was the subject of a Wiki Education Foundation-supported course assignment. Further details are available on the course page. Student editor(s): Dfmckeown.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 10:11, 17 January 2022 (UTC)

High-velocity stars

I have a hunch that the frame of reference should be average motion of the stars in the neighbourhood of the star we consider, not "in the Sun's neighbourhood". It is completely non-intuitive to think about almost all stars of the bulge and from other sectors of the Milky Way as "high-velocity stars" due to such a heliocentric prejudice. Incnis Mrsi (talk) 16:08, 9 August 2012 (UTC)

Was one from the LMC

There is a mention that one of the known Hypervelocity stars is believed to be from the Large Magellanic Cloud. As per this study: http://iopscience.iop.org/2041-8205/719/1/L23 It has been ruled out at the 3σ level. Just thought I'd mention it for you guys to consider... acoyauh (talk) 18:29, 3 October 2012 (CST)

catalan

please, add http://ca.wikipedia.org/wiki/Cinemàtica_estel·lar as a interwiki. Thanks! — Preceding unsigned comment added by 77.228.133.182 (talk) 19:25, 7 November 2012 (UTC)

new group discovered "Hypervelocity Star Candidates in the SEGUE G & K Dwarf Sample"

http://arxiv.org/abs/1308.3495

--Stone (talk) 19:20, 14 January 2014 (UTC)

HVS origin: White dwarf supernovae produce no neutron stars - huge mistake there

I strongly suggest consulting any classic text book for Astronomy 101 - and see that neutron stars result from core collapse supernovae. Other type of supernovae occur in white dwarfs as part of a binary system. These core detonation or white dwarf supernovae are a different type, not related with core collapse supernovae, where in fact neutron stars can be formed. This is not a matter of opinion, but one of the fundamental facts about supernovae. This is a blunt ugly error that should be corrected immediately.

I suggest a new article should be forked, focused specifically on "hyper-velocity stars"

I encounted this article when someone added a link to [[Stellar kinematics#High-velocity stars|hyper-velocity]].

In my opinion, if something is worthy of a wikilink it almost certainly deserves a standalone article.

IMO this article should say something like:

Hyper-velocity stars Main article: Hyper-velocity stars Hyper-velocity stars have acquired velocities greater than the escape velocity of our Galaxy. Events that speed up a star to hyper-velocity include: a close encounter with a super-massive black-hole; being a very close companion of a star that goes supernova.

Cheers! Geo Swan (talk) 18:39, 18 March 2015 (UTC)

Seems reasonable, but looking at the archive list (top right) it seems hypervelocity star was merged here some years ago. - Rod57 (talk) 14:31, 18 January 2020 (UTC)

rough work

"SDSS J091301.00+305120.0" "SDSS J091759.42+672238.7" "SDSS J110557.45+093439.5" "SDSS J113312.12+010824.9" "SDSS J094214.04+200322.1" "SDSS J102137.08-005234.8" "SDSS J120337.85+180250.4"

MansourJE (talk) 03:20, 4 May 2015 (UTC)

Runaway star

We have found many runaway stars, specially recently some have been recognized by scientists. These galaxies are escaping their home into infinity void space forever. Read more here:

http://phys.org/news/2015-04-astronomers-runaway-galaxies.html

MansourJE (talk) 07:48 May 2015 (UTC)

Inconsistencies on velocity?

Under Runaway stars, a runaway star is defined as "one that is moving through space with an abnormally high velocity relative to the surrounding interstellar medium." It gives the example of certain stars that are moving at 100km/s, and compares this to the Sun moving at 20 km/s faster than the local average. The problem here is that the 100 km/s is given as an absolute velocity rather than one relative to the surrounding interstellar medium, while the Sun's velocity is given as relative - so the comparison isn't working as intended.

Then in the Hypervelocity stars section, it's stated that ordinary stars move at 100 km/s - yet above in Runaway stars, 100 km/s is depicted as "abnormally high velocity." I think that a more precise description of these velocities is needed. Thanks. Wlegro (talk) 19:33, 22 February 2017 (UTC)

Two definitions or types of space velocity

Article says "the space velocity can be computed.[1] This is the star's actual motion relative to the Sun or the local standard of rest (LSR)." but later uses of space velocity do not clarify which definition is being used. Should we always specify, or is one the normal default ? - Rod57 (talk) 09:32, 18 January 2020 (UTC)

kinematic age

Just came across this phrase. No idea what it means. Might be something to include here. — kwami (talk) 13:42, 4 March 2020 (UTC)

It is the ratio of a size of an object and an expansion velocity, which gives an estimate of the age if this is not possible with other methods. It is often used in astronomy. Hobbema (talk) 11:13, 11 January 2024 (UTC)