Closest, Brightest Supernova In 21 Years Goes Boom In M82, The Cigar Galaxy

Before and after photo animation of the new bright supernova discovered overnight in the galaxy M82 in Ursa Major. Credit: Ernesto Guido, Nick Howes & Martino Nicolini

Like one of those famous exploding cigars in a Groucho Marx movie, nature imitates life by producing an exploding cigar of its own – a brand new, bright supernova in the “Cigar Galaxy” M82 in the Great Bear. It was discovered only last night by astronomer S. J. Fossey at magnitude 11.7. Very bright!

Even a 3-inch telescope under a dark sky can snare this one. While there have been brighter supernovae – and who knows, this one may very well get brighter yet – this is the brightest, closest supernova since SN 1993J popped off in neighboring galaxy M81.

The supernova in M82 is located 54″ west and 21″ south of the galaxy’s center along its long axis. Credit: Leonid Elenin

M82 goes by the nickname the Cigar Galaxy from its highly elongated shape. Through a small telescope it looks like a ghostly streak of light. At just 12 million light years from Earth it’s one of the closer galaxies to our home, making it bright enough to see in binoculars. Through a telecope, M82 is closely accompanied by the equally bright galaxy M81. Together they’re a favorite target on winter and spring nights for beginning and amateur astronomers.

M82 as pictured by the Hubble Space Telescope. A huge burst of new star formation is happening in the galaxy’s core. Click to enlarge. Credit: NASA/ESA

The big surprise is that no one found the object sooner. Most supernovae are spotted either by professional survey programs or amateur versions of the same when they’re around 15th magnitude or fainter. Not this one. It was brighter than 12th magnitude at discovery, but had someone been looking, it was easily visible in amateur instruments as early as January 16 at magnitude 13.9, brightening to 13.3 on the 17th and 12.2 on the 19th. Yikes! Why wasn’t I out looking at this galaxy?

The new supernova, with the temporary name of PSN J09554214+6940260, is a Type Ia explosion. In plain English, what we’re witnessing back here from our cozy homes on Earth is the complete annihilation of a super compact planet-size star called a white dwarf. Before anyone knew the star would explode, it spent millenia gravitationally siphoning off gas from a very close companion star. That material accumulated on its sizzling surface, adding to the weight of the little star. When the star reached the ultimate limit of 1.4 times the mass of the sun, it imploded under its own weight, heated up to billions of degrees and burned explosively. Boom! A supernova was born.

Use this map to point yourself in the right direction. It shows the sky facing north around 8 p.m. local time. M82 is paired with M81 about a “fist” above the bowl of the Big Dipper in the constellation Ursa Major. Stellarium

I know that the cold won’t keep you from wanting to see the new star so I’ve prepared a couple charts to help you find it. The first is a wide view to get situated; the second hones in to bring your directly to the galaxy. Be careful not to mix up M82 with its neighbor M81. M81 has a much rounder shape with a bright, distinct central core or nucleus. M82, an edge-on spiral galaxy, looks like a thin streak of light with a mottled texture. You’ll find the supernova west and south of M82’s center along the galaxy’s long axis. Look for a small star shining against the galaxy unresolved haze of stars.

To navigate to M82 find the Dipper Bowl and look above it for the easy naked eye star (mag. 3.5) 23 UMa. From there you can star hop to the triangular figure and down to the two stars forming a line. The galaxy is just below it. Stellarium
UPDATE: Sketch made Jan. 22 at 9 p.m. CST of M82 of the supernova, now called SN 2014J, through a 15-inch (37 cm) telescope. A wonderful arc of three bright stars (on left) guides you straight to it. You can’t miss it in telescopes 3 inches and up as the object is the only bright star shining in the galaxy. Numbers shown next to the stars are magnitudes to help you track the supernova’s brightness changes. Illustration: Bob King

Good luck in your quest to see one of the coolest sights in the night sky.

24 Responses

  1. steven

    Amazing, thanks Bob. Do you know what would happen to our planet and us if we were at a distance of (for example) 25 lightyears from this supernova?

      1. Bob Crozier

        Dwarf stars (red and white) are fairly common, aren’t they? Do we have many in our stellar neighborhood? And why don’t we see these supernova events more often? With untold billions of stars in each galaxy (and who knows how many galaxies that we can see), I would have expected that these kinds of events would be much more common. Have we ever seen one in our own galaxy?

        1. astrobob

          Yes, we’ve seen several in our galaxy over the past few hundred years. Remember, you need more than just a white dwarf (red dwarfs won’t do because they’re ordinary stars of light density compared to the compressive power of a white dwarf). That white dwarf also has to be closely orbiting another sunlike or larger star. Type Ia supernovae only occur in binary stars where a white dwarf is a member. Type II supernova involve the explosion of rare supergiant stars.

  2. Horace Smith

    Or perhaps one should say that it may become the apparently brightest supernova in 21 years. The 2011 type Ia supernova in M101 reached a little brighter than V = 10.0. M82 is closer than M101 and we might expect the new supernova to become brighter, all else being equal. However, the M82 supernova could be more dimmed by dust than the one in M101, It will be fun to see how bright it does get.

    1. astrobob

      Hi Horace,
      I had a twisty time with that one which is why I described it as “closest, brightest in 21 years” rather than the brightest. There have definitely been brighter supernovae as you point but not at this distance. 1987A is No. 1, 1993J #2 and this new one is #3 just behind 1993J in terms of the combined factors of distance and brightness. M101 is 20.9 million light years away.

  3. John Sponauer

    Just got back in from observing in central Connecticut. Clearly visible, when the wind settled down enough to stop moving my scope. Very hard to give a brightness rating, but there was a clear bright dot in M82 when viewing settled down. The two 10-ish magnitude stars near M82 on that side of it almost make a line right to the supernova, in my eyes.

    Baby, it’s cold outside. This is a crazy hobby. 🙂

    1. astrobob

      Great to hear John! I set my scope out a little while ago to fully chill. After dinner I’m hoping we have enough clear sky to catch a look. -7 F and extremely windy here too.

  4. Patrick Wiggins

    I imaged M-82 the nights of 14, 16, 17, 18, 19, 20, 21 and 22. It did not show up on any of those images. But then I went back and really stretched the histogram on each and found it lurking in the previously overexposed portions near the core of the galaxy on all but the 14th. So I’m calling it the supernova that (for me) got away. 🙂

    1. astrobob

      You and a number of other amateurs managed to catch it even if unaware at the time you had it. Your images could very well be important documents in understanding its early behavior.

  5. Brian

    How is it determined that the supernova is actually in M82 and not in our galaxy in the same line of sight as M82?

    1. astrobob

      This is a beautiful question. All Type Ia supernovae like this one explode with approximately the same amount of energy, so much so that they’re used as standard candles to measure distance. If you know the intrinsic brightness of a supernova explosion (which we know) and can measure the observed brightness, you can use the inverse square law to determine the distance to the object.

      If this supernova were a foreground Milky Way star it would be spectacularly brilliant – most likely outshining Venus due to its proximity to us. Instead, while bright, it still requires a telescope to see. Based on its brightness it’s far more distant. Astronomers can also measure the object’s redshift (they may have already) which will tell them it’s far outside the galaxy. Its redshift should be a near match for M82 itself. Similar measurements and distance factoring can be applied to other types of supernovae as well.

      1. Brian

        Ah, so kind of a “cosmic yardstick.” I find it amazing that the event happened ~11.4 million years ago and we are just now seeing it!

        Thanks, as always, for your reply!

  6. I’m going out observing tonight to track this down. I’m quite excited — I’ve missed the last few supernovae, and it looks like this one should be easy to catch. I wanted to thank you for the finder chart for M81/M32, which is *so* much easier to follow than my usual method (diagonal from Phecda to Dubhe).

    I don’t know if you’ve noticed this, but once you’re at the “Line” marked on your chart, there’s an arc of 7th to 9th magnitude stars, beginning from the brighter of the Line stars, that take you right to M82. That was how I finally found M82 for the first time a couple of years ago. 🙂

    Excellent column as always!

    1. astrobob

      Thanks Saint! I think you’ll have no problem seeing the SN. I’ve seen that arc – it may be the one I included in the updated version of the blog with a telescopic sketch.

  7. Giorgio Rizzarelli

    Thanx for the news Bob. I’m glad to take a look through the photos you posted, for now. Whether it was the warm side of the polar vortex or whatever, we’ve been having overcast all January with very few exceptions, which killed Jupiter opposition and Venus thin crescent. Now cold and wind, and me having a cold 🙂

    By the way check email, I sent you one about the recent detection of water vapor continuously supplied on Ceres, together with a small suggestion for the article which I’m sure you’ll going to write about.

    Which magnitude is the supernova expected to reach and when?

    1. astrobob

      I almost added Ceres to the mix because it was a water discovery but decided to let Opportunity be the focus. You’re right. I’ll have something on it. Sorry to hear about your cloudy skies. I saw the supernova last night and used the AAVSO chart to estimate its brightness at 11.6. Hard to say just how bright it might become – maybe 10.5 or even 10?? – before it fades.

  8. William

    Perhaps someone here can shed some light on something I observed recently. It was August 21st, at approximately 12:21 a.m. PST. I witnessed several distinct flashes of light. Each burst lasted a second at most. It looked like a bright star appeared, then vanished abruptly. I was looking to the north towards the Big Dipper, and the bursts of light appeared just above, and to the right of the star Dubhe. I seen 3 different bursts, and decided to note the time, and date. It was 12:25 a.m. at that point. Intrigued I kept staring at the spot for some time after, and seen consecutive, rapid bursts (all within the span of less than one second) in the UV range. That is to say it looked like a black light star. At the time I thought I had possibly witnessed a supernova. I did some digging, and found an article saying there was a type 1a supernova in M82 in January of this year. As far as I can tell that is right in the area where I seen these bursts of light. Am I just seeing things? Thoughts on the matter?

    1. astrobob

      Hi William,
      I wish I could say it was a supernova, but you saw something else. While the supernova in M82 was a bright one, it well below naked eye visibility. At least a 6-inch was needed to see it. Supernovae don’t flash on and off but rather brighten to a peak over days and sometimes longer. My guess is you saw reflections of light off a satellite or possibly twinkling from Dubhe. Did the flashing object move or stay still?

      1. William

        It was stationary (relatively speaking). That was why I found it so peculiar. I’ve certainly seen my share of satellites brighten then gradually dim, but they always have perceivable motion. Well thanks for the reply. I was rather hoping I saw something spectacular with naked eye, it would feel like winning the lotto.

        1. astrobob

          There is a satellite called EGP that moves relatively slowly and reflects light like a disco ball with repeated flashes. I’m thinking now it could have been this. The only thing is that EGP isn’t terribly bright.

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