Nova Delphini 2013 Brightens, Now Ranks Among Top 35 Brightest In History

A one-minute time exposure of the constellation Delphinus and the nova taken last night. I’ve labeled stars with magnitudes so you can track changes in the nova’s brightness. The magnitudes are visual ones taken from the Tycho catalog. Credit: Bob King

If it wasn’t for the bright moon, you’d be able to see the new nova with the naked eye even from the suburbs. But who knows? By tonight it could bust that barrier.

Last night Nova Delphini was magnitude 4.8 and still brightening. Richard Keen of Colorado saw it shortly before 2 a.m. this morning at 4.4. Already it’s some 10 times brighter than only two days ago at the time of its discovery. That puts it in the top 35 in recorded history!

I took a photo of Delphinus and the nova last night and annotated it with additional star magnitudes so you can watch it fluctuate in brightness in the coming nights. The smaller the number, the brighter the star.

Star atlases, like this view of Orion from Cambridge Atlas 2000.0, show star brightness as different sized dots. The smaller the dot, the fainter the star. Credit: Bob King

Astronomers use the magnitude scale to measure star and planet brightness. Each magnitude is 2.5 times brighter than the one below it. Deneb in the Northern Cross, which shines at 1st magnitude, is 2.5 times brighter than a 2nd magnitude star like the North Star, which in turn is 2.5 times brighter than a 3rd magnitude star and so on. A first magnitude star is 2.5 x 2.5 x 2.5 x 2.5 x 2.5 (about 100) times brighter than a 6th magnitude star, the typical naked eye limit under dark skies.

The larger the magnitude, the fainter the star. If something is very bright, its magnitude is a negative number. Vega shines at 0 mag. while Sirius, the brightest star, sparkles at -1.4 mag. Venus is brighter yet at -4.4. Click HERE for more information about star magnitudes.

Chart to help you find Nova Delphini 2013 with magnitudes shown. Stellarium

Keep an eye on the nova’s color. Right now it’s still in its explosive fireball phase and appears yellow through a telescope. That could change over the coming weeks as it either brightens or fades. Some novae turn a lovely pink. No matter what’s in store, you’ve got a front row seat as long as you have a good pair of binoculars and star chart. Go for it!

If you want the latest estimates of Nova Delphini’s brightness, go to and type in N Del 2013 in the Star finder box, then click “Check reecent observations”.

28 Responses

  1. Ej

    Is there anywhere to check its mag while its light here. Ie. is there some type of observing database where people from Japan / Russian can report it’s brightness while its sunny state side

  2. Edward O'Reilly

    This keeps getting better and better. One wonders just how bright our little friend in Delphinus is going to get.

    1. astrobob

      Great question! Yes. You can go to and type in N Del 2013 in the Star finder box, then click “Recent observations”.

  3. Edward M. Boll

    I drove out of town at 1. I looked up at Delphinus and if it was brighter than magnitude 5, I am sure that I saw it but I could not identify it because I had not taken my star charts. I did not see what I saw 3 days ago meteors but did see the very low Moon. In fact I saw it setting as I drove west, 5 minutes after I left the observing site. I drove to work shortly after and have not slept yet. The bed is going to be early tonight.

    1. astrobob

      Nothing like melting into sleep after a late night of skywatching. I’m glad you had clear skies to see the nova.

  4. Luis Lopes

    I just observed it at 8:48 pm UTC and its brightness is similar to that of zeta Del or magnitude 4.6. I think this one won´t keep brightening for much longer. But what a nice nova it is !

  5. Edward M. Boll

    After 4 hours of sleep, I drove a couple miles out and looked at the sky. It was cloudy in the south, too cloudy to see Delphinus although the Moon peaked out once in a while and really lit up the clouds. It still looked fairly day like. Although I like naked eye astronomy, I was thinking what I would see with a 10 inch telescope. If it was clear, I would look at the new 4th magnitude point of light in Delphinus. I could see Saturn and rings, and our Moon with a filter. If there were no Moon out, I could see perhaps 5 or so moons of Saturn, more than I could with Jupiter. Then don’t forget about Neptune near opposition. And then with a little more challenge Comet Lemmon. Those are just a few objects in our Solar System to see.

    1. astrobob

      We looked at Neptune just the other night. 240x plainly shows a disk and the moon Triton in my 15-inch.

  6. Bob G

    I had a very easy to naked eye view of the nova from Hammonassat Conn. camp site, c. 3AM EDT morning of 8/17. Estimated mag as 4.0, in between Delphinus and Sagitta where pre nova charts show no such star.

  7. Edward M. Boll

    I stepped outside from work at 6:35 AM this morning. Beautiful sunrise! I am going to make a 100 day prediction for Comet ISON. The morning of November 26, magnitude -2. But the comet shining in a bright twilight sky might not be viewed by most without a pair of binoculars before sunrise.

  8. Tom Van Dyke

    Do we know the distance to the star so we can determine how long ago this event took place and the light is just now reaching earth?

    1. astrobob

      Hi Tom,
      None that I can find yet. I’m guessing at least 1,000 light years since the progenitor star was very faint.

  9. Scott detweiler

    I am in Woodland Hills, CA, just north if Los Angeles, and looking at Nova Delphini (9:26 PST). Just above Altair, barely visible with the naked eye (due to the fill moon), it reminds me if Betlegeuse in color.

    1. astrobob

      Thanks Scott for your observation. The nova’s definitely a warm color. I noticed it tonight in a telescope

    1. astrobob

      We don’t know yet but based on similar novae, it’s likely in the range of 1,000 to 1,500 light years.

      1. wow thank you. im an astronomy and astrophysics fan for a couple of years now and this its really awesome to see one so close 😀 if only we could see one as bright as the one who made the crab nebula.
        it would make my life. lol soory my english

        1. astrobob

          I’m hoping as much as you for a Crab-style supernova in our galaxy in our lifetime. We’re due!

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