Rising Star Month on January, 2018: if you see the star sirius rise at 10 am what time will it rise one month later
January, 2018 is Rising Star Month 2018. RISING_STARS_LOGO.jpg star student rising star
One month from now, the stars are in the same position in the sky about 2 hours earlier.
Of course, if you're seeing stars rise at 10am, you're probably pretty close to the north pole right now, and Sirius is probably below the horizon. But assuming you can see it rise in the daytime, it would rise at ~8am in a month. Sirius is rising around 10pm these days ... so in a month, it will rise ~8pm
If a star rises at 8:30pm tonight, approximately what time will it rise 2 months from now?
Linda has her numbers right but the direction wrong. A star rises EARLIER each night. If you're out all night doing astronomy these days you know that you see Vega rising at 2:19 a.m. (on January 20). It will rise at 17 minutes past midnight on February 20th, and so on; in the late spring and summer, it dominates the early evening sky.
This gives a star the appearance of traveling west as the season progresses. Summertime, Vega is directly overhead; in the autumn it appears in the western sky and is heading down fast. It appears way over there because it actually rose EARLIER--in the daytime--and has traveled all the way to the western part of the sky by the time it gets dark.
To sum up: 3 minutes 56 seconds EARLIER each calendar day, most people just call it four minutes and let it go at that.
To get technical about it, there are two things to think about.
1. The further north you go, the longer the star is in the sky. At the North pole in January, most stars neither rise nor set. So rising and setting times have to be adjusted to your location.
2. Even if you are in the regular ol' USA there are a number of CIRCUMPOLAR STARS that never rise nor set. Kochab in the little dipper is a good example. The farther N you go, the more circumpolar stars there are; at the N pole, they are all circumpolar.
So the four minute thing is really for the equator. If your teacher is sort of average he or she will think the four minute thing is a rule about stars. NO! It's not a rule about stars rising and setting; it's a rule about the EARTH's ROTATION and is getting at the idea of SIDEREAL TIME. Stars' rising and setting varies with LATITUDE.
If your teacher is SMART, it's a TRICK QUESTION, and you'll need to throw something in about circumpolar stars.
Today at 42 N Latitude Vega rises at 2:19 a.m.; 5 degrees N, at 47 N Latitude, it rises about an hour earlier; and at 52 degrees N latitude it becomes circumpolar and never rises nor sets.
I suppose you could say: if I stay in the same place, a star that rises (not all do) will rise 3:56 seconds EARLIER each night. So long as I don't travel N or S that rule will hold.....and a star that rises at 8:30 p.m. TONIGHT Jan 20 will rise at 4:30 p.m. on March 20.
hope that helps,
If there was a star (not the Sun) which rises at 9 p.m. tonight. What time will it rise three months from now?
Stars rise 4 minutes earlier every day.
So in three months you have, lets say 90 days, that is 360 minutes or 6 hours. The star will rise at 9-6=3pm.