APOD: M1: The Incredible Expanding Crab Nebula (2020 Jan 19)

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 4478
Joined: Fri Dec 04, 2009 3:27 am

APOD: M1: The Incredible Expanding Crab Nebula (2020 Jan 19)

Post by APOD Robot » Sun Jan 19, 2020 5:05 am

Image M1: The Incredible Expanding Crab Nebula

Explanation: Are your eyes good enough to see the Crab Nebula expand? The Crab Nebula is cataloged as M1, the first on Charles Messier's famous list of things which are not comets. In fact, the Crab is now known to be a supernova remnant, an expanding cloud of debris from the explosion of a massive star. The violent birth of the Crab was witnessed by astronomers in the year 1054. Roughly 10 light-years across today, the nebula is still expanding at a rate of over 1,000 kilometers per second. Over the past decade, its expansion has been documented in this stunning time-lapse movie. In each year from 2008 to 2017, an image was produced with the same telescope and camera from a remote observatory in Austria. Combined in the time-lapse movie, the 10 images represent 32 hours of total integration time. The sharp, processed frames even reveal the dynamic energetic emission within the incredible expanding Crab. The Crab Nebula lies about 6,500 light-years away in the constellation Taurus.

<< Previous APOD This Day in APOD Next APOD >>

User avatar
Ann
4725 Å
Posts: 11650
Joined: Sat May 29, 2010 5:33 am

Re: APOD: M1: The Incredible Expanding Crab Nebula (2020 Jan 19)

Post by Ann » Sun Jan 19, 2020 5:39 am

Okay, nice video... 5 seconds long!

I prefer the stunning time-lapse movie link. There the five second movie is on a loop, and the Crab looks like a beating heart, obviously expanding and (falsely) contracting. Anyway, you can easily spot the size difference there!

Ann
Last edited by Ann on Sun Jan 19, 2020 2:18 pm, edited 1 time in total.
Color Commentator

Boomer12k
:---[===] *
Posts: 2691
Joined: Sun Apr 22, 2007 12:07 am

Re: APOD: M1: The Incredible Expanding Crab Nebula (2020 Jan 19)

Post by Boomer12k » Sun Jan 19, 2020 6:01 am

Evidently, it is still CRABBY!!!!

:---[===] *

User avatar
neufer
Vacationer at Tralfamadore
Posts: 18560
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

CRABBY APPLETON "Rotten To The Core!"

Post by neufer » Sun Jan 19, 2020 12:51 pm

Ann wrote:
Sun Jan 19, 2020 5:39 am

I prefer the stunning time-lapse movie link. There the five second movie is on a loop, and the Crab looks like a beating heart, obviously expanding and (falsely) contracting. Anyway, you can easily spot the size difference there!
Boomer12k wrote:
Sun Jan 19, 2020 6:01 am

Evidently, it is still CRABBY!!!!
https://en.wikipedia.org/wiki/Tom_Terrific wrote: <<Tom Terrific is an early animated series on American television, presented as part of the Captain Kangaroo children's television show. Drawn in a simple black-and white style reminiscent of children's drawings, it featured a gee-whiz boy hero, Tom Terrific, who lived in a treehouse and could transform himself into anything he wanted thanks to his magic, funnel-shaped "thinking cap," which also enhanced his intelligence. He had a comic lazybones of a sidekick, Mighty Manfred the Wonder Dog, and an arch-foe named Crabby Appleton, whose motto was, "I'm rotten to the core!" Other foes included Mr. Instant the Instant Thing King; Captain Kidney Bean; Sweet Tooth Sam the Candy Bandit; and Isotope Feeney the Meany. All the voices were performed by Lionel Wilson (who later voiced Eustace Bagge from the Cartoon Network series Courage the Cowardly Dog).>>
Art Neuendorffer

User avatar
orin stepanek
Plutopian
Posts: 6986
Joined: Wed Jul 27, 2005 3:41 pm
Location: Nebraska

Re: APOD: M1: The Incredible Expanding Crab Nebula (2020 Jan 19)

Post by orin stepanek » Sun Jan 19, 2020 1:49 pm

Ann wrote:
Sun Jan 19, 2020 5:39 am
Okay, nice video... 5 seconds long!

I prefer the stunning time-lapse movie link. There the five second movie is on a loop, and the Crab looks like a beating heart, obviously expanding and (falsely) contracting. Anyway, you can easily spot the size difference there!

Ann

Thanks Ann; that is a stunning time lapse!
Orin

Smile today; tomorrow's another day!

another guest

Re: APOD: M1: The Incredible Expanding Crab Nebula (2020 Jan 19)

Post by another guest » Sun Jan 19, 2020 5:13 pm

In case you are not aware, the gear icon on the bottom right of the screen has picture quality and speed. Click on it and you can reduce the speed up to 75% making the vid last 20 seconds.

ptahhotep
Ensign
Posts: 12
Joined: Wed Oct 23, 2019 5:32 pm

Re: APOD: M1: The Incredible Expanding Crab Nebula (2020 Jan 19)

Post by ptahhotep » Sun Jan 19, 2020 5:16 pm

I remember one of the first exercises on my astrophysics course was working out the expansion rate of the Crab using pictures taken over a period of about a hundred years.

dddavids@iupui.edu

Re: APOD: M1: The Incredible Expanding Crab Nebula (2020 Jan 19)

Post by dddavids@iupui.edu » Sun Jan 19, 2020 9:42 pm

Thanks for the cycling video link. Are the 2 stationary stars at the center of the expanding nebula actually within the cloud?

User avatar
neufer
Vacationer at Tralfamadore
Posts: 18560
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: M1: The Incredible Expanding Crab Nebula (2020 Jan 19)

Post by neufer » Sun Jan 19, 2020 10:43 pm

dddavids@iupui.edu wrote:
Sun Jan 19, 2020 9:42 pm

Are the 2 stationary stars at the center of the expanding nebula actually within the cloud?
https://en.wikipedia.org/wiki/Crab_Nebula#Central_star wrote: <<At the center of the Crab Nebula are two faint stars, one of which is the star responsible for the existence of the nebula. It was identified as such in 1942, when Rudolf Minkowski found that its optical spectrum was extremely unusual. The region around the star was found to be a strong source of radio waves in 1949 and X-rays in 1963, and was identified as one of the brightest objects in the sky in gamma rays in 1967. Then, in 1968, the star was found to be emitting its radiation in rapid pulses, becoming one of the first pulsars to be discovered.

The Crab Pulsar is believed to be about 28–30 km in diameter; it emits pulses of radiation every 33 milliseconds. Pulses are emitted at wavelengths across the electromagnetic spectrum, from radio waves to X-rays. Like all isolated pulsars, its period is slowing very gradually. Occasionally, its rotational period shows sharp changes, known as 'glitches', which are believed to be caused by a sudden realignment inside the neutron star. The energy released as the pulsar slows down is enormous, and it powers the emission of the synchrotron radiation of the Crab Nebula, which has a total luminosity about 75,000 times greater than that of the Sun.

The pulsar's extreme energy output creates an unusually dynamic region at the centre of the Crab Nebula. While most astronomical objects evolve so slowly that changes are visible only over timescales of many years, the inner parts of the Crab Nebula show changes over timescales of only a few days. The most dynamic feature in the inner part of the nebula is the point where the pulsar's equatorial wind slams into the bulk of the nebula, forming a shock front. The shape and position of this feature shifts rapidly, with the equatorial wind appearing as a series of wisp-like features that steepen, brighten, then fade as they move away from the pulsar to well out into the main body of the nebula.>>
Art Neuendorffer