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Jul
10
comment Why is right ascension measured in hours?
@Dieudonné Moreover, a sidereal second is defined regarding Earth's rotation referring to "fixed stars" (so, to the catalog equinox). Please cf. en.wikipedia.org/wiki/Sidereal_time and the definition there: Sidereal time, at any moment (and at a given locality defined by its geographical longitude), more precisely Local Apparent Sidereal Time (LAST), is defined as the hour angle of the vernal equinox at that locality: it has the same value as the right ascension of any celestial body that is crossing the local meridian at that same moment. Since it is defined as HA, it is a time.
Jul
10
answered What is the difference between a dwarf spheroidal galaxy and a globular cluster?
Jul
9
comment Why is right ascension measured in hours?
@Dieudonné You are wrong. Sidereal time is a time, measured in Sidereal seconds, not in degrees.Please check e.g. Wikipedia: en.wikipedia.org/wiki/Sidereal_time Local Sidereal Time at any locality differs from the Greenwich Sidereal Time value of the same moment, by an amount that is proportional to the longitude of the locality. When one moves eastward 15° in longitude, sidereal time is larger by one sidereal hour (note that it wraps around at 24 hours). I have actually used sidereal time clocks in my observations.
Jul
9
reviewed Edit What is the explanation for rapid inflation just after the big bang?
Jul
9
revised What is the explanation for rapid inflation just after the big bang?
Corrected grammar for clarity,
Jul
9
awarded  Custodian
Jul
9
reviewed No Action Needed Is there a radius inside of which objects are (doppler) blue shifted?
Jul
8
revised Why is right ascension measured in hours?
Ops... I used North Horizon and it is South Horizon
Jun
24
comment Is there a flaw with the newer purposes and correlations attributed to the HR diagram? (And would a third axis of mass correct the enclosed flaw?)
You need to write an article about the 3D diagram, its advantages, some use cases, fancy images, and send it to some academic magazine.
Jun
24
reviewed Approve Was the progress of astronomy in the 1800s surprisingly slow, and if so why?
Jun
24
reviewed Looks OK Escaping a black hole
Jun
24
reviewed Leave Open One year on the sun
Jun
24
answered Is there a flaw with the newer purposes and correlations attributed to the HR diagram? (And would a third axis of mass correct the enclosed flaw?)
Jun
20
answered How does water exist within the frost line of a star?
Jun
19
reviewed Reject Did big bang happen only one time or it might happen again somewhere million time away from our observable universe?
Jun
16
reviewed Approve How are black holes doors to other universes?
May
28
reviewed Approve Did we ever actually see the earth revolving around the sun? Is the geocentric model completely disproved?
May
28
reviewed Approve Did the Babylonians believe in the Heliocentric version?
May
28
reviewed Close What study profiles could land me the job of astronomer?
May
28
comment What study profiles could land me the job of astronomer?
This question appears to be off-topic because it is about professional skills