UPDATE
At the time that this alert is being written, sky watchers in Europe as far south as Germany are reporting red and green Northern Lights.
And you were telling me that on the south coast, you'd never see them!
youf of today!
firstly, the clue is in the name, Northern, so thats where they are to be seen, if there is something S I M I L A R seen down souf that its name will have to change, something catchy, like northern lights seen down souf or similar.
secondly, the krauts are reportedly seeing red and green, obviously confusing the traffic lights here.
here endeth the astro-physics lesson today.
tonite's homework, either, write no less than a 2500 word essay on:-
Distances and Magnitudes
the parallax angle for the star Sirius is 0.377"
a) find the distance to Sirius in units of (i) parsecs; (ii) light years; (iii)AU; (iv) cm.
b) determine the distance modulos for Sirius.
c) Sirius has a V apparent magnitude of -1.46. The bolometric correction for Sirius is BC=-0.09. Using the information above determine the absolute bolometric magnitude of Sirius and compare it to that of the Sun, Msun=4.76. What is the ratio of Sirius' luminousity to that of the Sun?
OR
Write your name in CAPITAL LETTERS.
a) find the distance to Sirius in units of
(i) parsecs; 2.6 A parsec is a unit of distance equal to about 3.3 light years, or 3.1 x 1016 meters
(ii) light years; 8.6 Lights travels at a finite speed of 299,792,500 metres per second which is about 9,460,000,000,000 kilometres per year.
(iii)AU; 4.6 or 543,861
(iv) cm. Silly question
b) determine the distance modulos for Sirius. The star Sirius has a magnitude of about -1.5
c) What is the ratio of Sirius' luminousity to that of the Sun?
Sirius is 8.6 lyr distant, and magnitude −1.47.
LSirius = 0.0813 · 8.62 · 10−0.4·(−1.47) = 23.3 ×
You can say that Sirius is 23 times brighter than the sun, or it radiates 23 suns.
>Martini...LB
