There’s a new star in the sky this month.
This new star is a nova (Latin, "new"–duh!).
It’s actually a nova that we’ve known about for a while, but you normally can’t see it with the naked eye.
Why can we see it now?
The star is RS Ophiuchi, and it is a very rare kind of star, known as a recurrent nova–a nova that doesn’t just brighten up once but does so repeatedly.
There are only seven known stars that behave like RS Ophiuchi.
Here’s how it works: In its star system there are two stars: a red giant and a white dwarf.
Matter from the red giant is spilling out and forming an accretion disk around the white dwarf.
The white dwarf itself doesn’t have the mass needed for additional fusion reactions, so it slowly cools down.
But if there is another body–like a nearby red giant–discharging matter then eventually the matter in the accretion disk around the white dwarf gets massive enough that fusion can occur, and then
BANG!
there’s new nova outburst as it blows this matter outward. Hence: recurrent nova.
RS Ophiuchi is currently experiencing an outburst, which made it bright enough to be seen with the naked eye (normally you have to use artificial magnification to see it). The outburst was first noticed in February, and astronomers all over the world have been watching.
Why?
Because RS Ophiuchi doesn’t do this very often. The last time was in 1985, or 21 years ago.
I don’t know if the star has faded to the point that it can no longer be seen with the naked eye, but if not then this may be your last chance to see it with the naked eye for . . . quite a while. We don’t know when it’ll flare up again.
LISTEN TO A SLACKER ASTRONOMY STORY ON THE CURRENT FLARE UP OF RS OPHIUCHI.
All through the long hellish hours of blackness it shines there… winking hideously like an insane watching eye…
“Ophiuchus” is from the Greek for “serpent holder.”
“Ophiuchus” is from the Greek for “serpent holder.”
P.S.
Ophiuchus is also the name of one of the THIRTEEN, not twelve, constellations of the zodiac that our sun’s travels actually intersect. That’s one reason why “astrology” is really “astrostupidity.”
Another reason. Astrostupidity claims that the sun’s positions coincide with specific constellations in the zodiac at particular times of the year. However, the zodiac calendar that astrostupidity uses is out of whack. The stars have not been in those positions for thousands of years.
Update on RS Ophiuchi’s brightness from Sky and Telescope:
“Update March 2: As of this morning RS Oph is down to about magnitude 8.1. Its rate of decline has greatly slowed — from 0.4 magnitude per day during the first few days after outburst to about 0.1 magnitude per day now. In a telescope the star appears distinctly orange.”
So it looks like one would need more than the naked eye at this stage.
Do I have to be the first to mention the 3rd-season opener of ST:TNG?
I beg to differ, Jimmy. The CURRENTLY may or may not be experiencing an outburst. Because it is so far away, (a distance that astronomers technically refer to as a billion trillion sagans), what we are actually seeing now is what the star did a very long time ago.
This event we are seeing has ended a long time ago and thus, is one of nature’s reruns (just like ST:TNG).