APOD: Wolf-Lundmark-Melotte (2016 Apr 07)

[bystander]

Well, that still doesn't tell me much of anything about the details of today's image, or the subsequent processing. Things like filters, exposure times, and subexposure count (if any) would be very useful information.

Filters and color mapping can be found here.

[Chris Peterson]

Well, that still doesn't tell me much of anything about the details of today's image, or the subsequent processing. Things like filters, exposure times, and subexposure count (if any) would be very useful information.

Filters and color mapping can be found here.

Thanks. I looked for that earlier. It's pretty well hidden from the linked news page.

[Boomer12k]

Interesting little galaxy.

Wonder why so far at the edge. Wonder why Irregular... as it should develop some structure, I would think, on its own as it is... even elliptical... but there is dust and gas there, as evidenced by Star Formation... maybe it was a LEFT OVER...that got ejected EARLY... a pocket of gas and dust, and it just doesn't have the specific gravity to pull anything together....

Wander on little galaxy...
:---[===] *

[neufer]

At 3 million light years distance, are we seeing individual stars in WLM ?

Yeah, the brightest stars and stellar systems are indeed showing up as single points.

• Not from the stars do I my iudgement plucke,
  And yet me thinkes I haue Astronomy, - Sonnet 14

[b][color=#0000FF][size=125]We see individual stars at 109 Mly in NGC 4603.[/size][/color][/b]

---

<<NGC 4603 is a spiral galaxy in the constellation Centaurus. It is a member of the Centaurus Cluster of galaxies, belonging to the section designated "Cen30".

During 1999, this galaxy was the subject of an extended study using the Hubble Space Telescope to locate Cepheid variable stars. A total of 43±7 were found, and the measurement of their periodicity gave a net distance estimate of 108.7 Mly (±5%). This is consistent with the distance estimate determined through redshift measurements. As of the time of this study, NGC 4603 was the most distant galaxy for which a distance estimate had been made using Cepheid variable.

On May 21, 2008, supernova SN 2008cn was discovered at a position 12kly north and 2.5kly east of the galaxy center. It was determined to be a high-luminosity Type II-P supernova, with a progenitor tentatively identified as a red supergiant with 15 ± 2 solar masses. Based upon the yellowish color, it may have been a member of a binary star system.>>

[Chris Peterson]

At 3 million light years distance, are we seeing individual stars in WLM ?

Yeah, the brightest stars and stellar systems are indeed showing up as single points.

That's the key factor: brightness (and isolation). Sometimes, all we need is a pair of binoculars to see an individual star in another galaxy- as when there's a supernova! And lots of amateur images of galaxies made with small telescopes will show a few isolated bright stars. The impressive thing that we see with very large telescopes (or HST) is individual stars starting to be resolved out of star clouds.

[neufer]

At 3 million light years distance, are we seeing individual stars in WLM ?

Yeah, the brightest stars and stellar systems are indeed showing up as single points.

That's the key factor: brightness (and isolation).
And lots of amateur images of galaxies made with small telescopes will show a few isolated bright stars.

The catch is:

• If one wishes on an isolated bright star in another galaxy
  it takes a lot longer to get a response.

<<In Meteorologica (DK 59 A80), Aristotle (384–322 BC) wrote that the Greek philosophers Anaxagoras (c. 500–428 BC) and Democritus (460–370 BC) proposed that the Milky Way might consist of distant stars. The Persian astronomer Abū Rayhān al-Bīrūnī (973–1048) proposed that the Milky Way is "a collection of countless fragments of the nature of nebulous stars". The Andalusian astronomer Avempace (d 1138) proposed the Milky Way to be made up of many stars but appears to be a continuous image due to the effect of refraction in Earth's atmosphere. Ibn Qayyim Al-Jawziyya (1292–1350) proposed that the Milky Way is "a myriad of tiny stars packed together in the sphere of the fixed stars" and that these stars are larger than planets. According to Jamil Ragep, the Persian astronomer Naṣīr al-Dīn al-Ṭūsī (1201–1274) in his Tadhkira writes: "The Milky Way, i.e. the Galaxy, is made up of a very large number of small, tightly clustered stars, which, on account of their concentration and smallness, seem to be cloudy patches. Because of this, it was likened to milk in color." Actual proof of the Milky Way consisting of many stars came in 1610 when Galileo Galilei used a telescope to study the Milky Way and discovered that it is composed of a huge number of faint stars.>>

[Chris Peterson]

The catch is:

• If one wishes on an isolated bright star in another galaxy
  it takes a lot longer to get a response.

Are you suggesting that wishes are bound by special relativity?

[neufer]

The catch is:

• If one wishes on an isolated bright star in another galaxy
  it takes a lot longer to get a response.

Are you suggesting that wishes are bound by special relativity?

Only special wishes...general wishes might make use of a worm hole.