APOD: A Bright Nova in Cassiopeia (2021 Jun 07)

[APOD Robot]

A Bright Nova in Cassiopeia

Explanation: What's that new spot of light in Cassiopeia? A nova. Although novas occur frequently throughout the universe, this nova, known as Nova Cas 2021 or V1405 Cas, became so unusually bright in the skies of Earth last month that it was visible to the unaided eye. Nova Cas 2021 first brightened in mid-March but then, unexpectedly, became even brighter in mid-May and remained quite bright for about a week. The nova then faded back to early-May levels, but now is slightly brightening again and remains visible through binoculars. Identified by the arrow, the nova occurred toward the constellation of Cassiopeia, not far from the Bubble Nebula. A nova is typically caused by a thermonuclear explosion on the surface of a white dwarf star that is accreting matter from a binary-star companion -- although details of this outburst are currently unknown. Novas don't destroy the underlying star, and are sometimes seen to recur. The featured image was created from 14 hours of imaging from Detroit, Michigan, USA. Both professional and amateur astronomers will likely continue to monitor Nova Cas 2021 and hypothesize about details of its cause.

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[1lostone]

This is an awesome capture and you must see this full screen to really appreciate the capture.

[orin stepanek]

I wonder how many of these we see, but don't realize what we are looking at?


Sorry but kitty wouldn't transfer for me/ but you can click on hypothesize to see the kitty!
and hypothesize about details of its cause.

[Ann]

Sorry but kitty wouldn't transfer for me/ but you can click on hypothesize to see the kitty!
and hypothesize about details of its cause.

Click to view full size image

You mean this one, Orin?

Ann

[orin stepanek]

Sorry but kitty wouldn't transfer for me/ but you can click on hypothesize to see the kitty!
and hypothesize about details of its cause.

Click to view full size image

You mean this one, Orin?

Ann

Thanks Ann; I don't know why that occurs for me!

[neufer]

The featured image was created from 14 hours of imaging from Detroit, Michigan, USA.

<<Lake Hudson State Recreation Area is a public recreation area located within southwestern Lenawee County in the U.S. state of Michigan. The park was established in 1979, and it encompasses 2,796 acres surrounding the Lake Hudson reservoir. Lake Hudson is recognized as the first dark-sky preserve in the United States, when it was designated as such in 1993. It is currently one of seven such preserves in the state of Michigan, along with Negwegon State Park, Port Crescent State Park, Rockport State Recreation Area, Thompson's Harbor State Park, Wilderness State Park, and the internationally recognized Headlands Dark Sky Park. As required by the designation, the park must utilize measures to reduce light pollution, such as dimming headlights and outdoor lighting.>>

[neufer]

<<Thomas Allen (or Alleyn) (21 December 1542 – 30 September 1632) was an English mathematician and astrologer. John Aubrey (12 March 1626 – 7 June 1697) later wrote:

Click to play embedded YouTube video.

Mr Allen was a very cheerful, facetious man and everybody loved his company; and every House on their Gaudy Days were wont to invite him. The Great Dudley, Earl of Leicester, made use of him for casting of Nativities, for he was the best Astrologer of his time. Queen Elizabeth sent for him to have his advice about the new star that appeared in the Swan or Cassiopeia ... to which he gave his judgment very learnedly. In those dark times, Astrologer, Mathematician and Conjurer were accounted the same thing; and the vulgar did verily believe him to be a conjurer. He had a great many mathematical instruments and glasses in his chamber, which did also confirm the ignorant in their opinion; and his servitor [servant] (to impose on Freshmen and simple people) would tell them that sometimes he should meet the spirits coming up his stairs like bees. ... He was a handsome, sanguine man and of excellent habit or body.>>

[Avalon]

I'm sorry, but I would like to know which dot this arrow is supposed to be pointing at. It doesn't look precise enough for me to tell. Perhaps a circle can be placed around the nova? Thanks.

[Chris Peterson]

I'm sorry, but I would like to know which dot this arrow is supposed to be pointing at. It doesn't look precise enough for me to tell. Perhaps a circle can be placed around the nova? Thanks.

It's pointing at the brightest star that lies between the tip of the arrow and the edge of the frame.

[VictorBorun]

any idea how far Nova Cas 2021, or V1405 Cas, or CzeV3217 is?

[johnnydeep]

any idea how far Nova Cas 2021, or V1405 Cas, or CzeV3217 is?

I'd guess we'd need to know what star was there before it went nova and then find out if that star is in any stellar distance databases. Here's an interesting "blink comparison" of a before and after pic with coordinate lines. You could approximate the exact coordinates from that I suppose.

https://www.astrobin.com/89stbw/

Maybe one of the database jockeys that posts here probably might already know which star it is

Or, is this a "recurrent" nova for which we can determine distance solely by relative magnitude? Though the relatively frequent brightening and fading of this nova might not count as recurrent. See https://en.wikipedia.org/wiki/Nova#Nova ... indicators :

Recurrent novae (RNe) are objects that have been seen to experience multiple nova eruptions. As of 2009, there are ten known galactic recurrent novae,[21] as well as several extragalactic ones (in the Andromeda Galaxy (M31) and the Large Magellanic Cloud). One of these extragalactic novae, M31N 2008-12a, erupts as frequently as once every 12 months. The recurrent nova typically brightens by about 8.6 magnitudes, whereas a classic nova may brighten by more than 12 magnitudes.[21] The ten known galactic recurrent novae are listed below.

But this nova isn't yet listed in the table of 10 galactic recurrent nova in the article. Maybe it never will be...

[ EDIT: D'oh! I now see that VistorBorun's posted link already points to the known pre-cursor variable star. ]