Starship Asterisk*

Nitpicker wrote:

ta152h0 wrote:
would distances be more accurately calculated from distances, let's say Jupiter's orbit and 180 degrees apart ?

Not for galaxies, but the parallax method from Jupiter would allow us to measure accurate distances to more nearby stars (a bit further away), than the current Earth-bound parallax methods.

https://en.wikipedia.org/wiki/New_Horizons#Long-Range_Reconnaissance_Imager_.28LORRI.29 wrote:
<<New Horizons has maneuvered for a January 1, 2019 flyby of Kuiper belt object 2014 MU69 when it is 43.4 AU from the Sun. The Long-Range Reconnaissance Imager (LORRI) is a long-focal-length imager designed for high resolution and responsivity at visible wavelengths. The instrument is equipped with a 1024×1024 pixel by 12-bits-per-pixel monochromatic CCD imager with a 208.3 mm (8.20 in) aperture giving a resolution of 5 μrad (~1 arcsec).

In August 2013, it was proposed to use the radio-tracking data from New Horizons to discover indications on the position of a hypothesized trans-Neptunian planetary-sized body.>>

ta152h0 wrote:would distances be more accurately calculated from distances, let's say Jupiter's orbit and 180 degrees apart ?

Nitpicker wrote:

DavidLeodis wrote:I wonder how much the image 'light' of M101 has spread out since it first came our way such perhaps that our view of M101 is blurred (like the light from a torch spreads out as it goes further from the torch).

Not blurred, but dimmed. Only a tiny portion of the light from M101 reaches Earth. Imagine the Earth intersecting the surface of a sphere of 27 million light years radius around M101. The surface area of the sphere represents all the light emitted by M101 in an instant, but the Earth occupies only the tiniest portion of that surface area, so we can only observe a tiny fraction of its light.

DavidLeodis wrote:I wonder how much the image 'light' of M101 has spread out since it first came our way such perhaps that our view of M101 is blurred (like the light from a torch spreads out as it goes further from the torch).

neufer wrote:
<<Chief among the uncertainties tied to the classical and type II Cepheid distance scale are: the nature of the period-luminosity relation in various passbands, the impact of metallicity on both the zero-point and slope of those relations, and the effects of photometric contamination (blending) and a changing (typically unknown) extinction law on Cepheid distances. All these topics are actively debated in the literature.

Ann wrote:

Nitpicker wrote: [sacrilege] Meh, not being much of a galaxy person, they're mainly just numbers to me. [/sacrilege]

[snicker(s)][/snicker(s)]

Oh wait, I mean...

[galaxy][/galaxy]

Note the blue star formation in the galaxy!

Ann

The worldwide Mars bar differs from what is sold in the US. The American version was discontinued in 2002 and was replaced with the slightly different Snickers Almond. The US version of the Mars bar was relaunched in January 2010 and is initially being sold on an exclusive basis through Walmart stores. The European version of the Mars bar is also sold in some United States grocery stores. It was once again discontinued at the end of 2011.

The British and Canadian Mars bars are very similar to the United States Milky Way bar, which Mars, Inc. produced (not to be confused with the European version of Milky Way, which is similar to the United States' 3 Musketeers).

ta152h0 wrote:
Light century must be a Star Wars thing. Tis the season ..........

• It's been suggested that the 99 years from 1AD thru 99 AD
  be called the first "century" but that never quite caught on.

http://www.seinology.com/scripts/script-154.shtml wrote:
Episode 154 - The Millennium
Broadcast date: May 1, 1997

NEWMAN: To the Newmanniun! (holds out his hand)

KRAMER: (grasps Newman's hand) To the Kramennium.

(Kramer and Newman move to the door to leave. Newman stops as Jerry speaks to him, and Kramer exits to his apartment.)

JERRY: By the way Newman, I'm just curious.
When you booked the hotel, did you book it for the millennium New Year?

NEWMAN: (smug) As a matter of fact, I did.

JERRY: Oh, that's interesting, because as everyone knows, since there was no year zero, the millennium doesn't begin until the year two-thousand and one. Which would make your party, one year late, and thus, quite lame.

(Newman absorbs the logic of Jerry's argument. His face twitches as he realises his error.)

JERRY: Aww!

(Newman makes a noise redolent of his frustration - a sort of half-strangulated nasal squeak. He then waddles away after Kramer.)

Chris Peterson wrote:

neufer wrote:

inertnet wrote:
That's funny, NASA and Wikipedia say 21 million [light years], the Messier catalog
says 27 [million light years] and many others say in between. So who's right?

• As of 13 September 2011: NASA & Wikipedia.

Perhaps more relevant, the primary source referenced by Wikipedia,
A New Cepheid Distance to the Giant Spiral M101 Based On Image Subtraction of HST/ACS Observations.

https://en.wikipedia.org/wiki/Cepheid_variable#Uncertainties_in_Cepheid_determined_distances wrote:
<<Chief among the uncertainties tied to the classical and type II Cepheid distance scale are: the nature of the period-luminosity relation in various passbands, the impact of metallicity on both the zero-point and slope of those relations, and the effects of photometric contamination (blending) and a changing (typically unknown) extinction law on Cepheid distances. All these topics are actively debated in the literature.

Click to play embedded YouTube video.

These unresolved matters have resulted in cited values for the Hubble constant (established from Classical Cepheids) ranging between 60 km/s/Mpc and 80 km/s/Mpc. Resolving this discrepancy is one of the foremost problems in astronomy since the cosmological parameters of the Universe may be constrained by supplying a precise value of the Hubble constant. Uncertainties have diminished over the years, due in part to discoveries such as RS Puppis.

RS Puppis (or RS Pup) is a Cepheid variable star in the constellation of Puppis. It is one of the brightest known Cepheids in the Milky Way galaxy and has one of the longest periods of 41.4 days. Because it is located in a large nebula, astronomers using the ESO's New Technology Telescope at La Silla Observatory, Chile have been able to measure its distance in 2013 by strictly geometric analysis of light echoes from particles in the nebula, determining it to be 6500 ± 90 light years from Earth, the most accurate measurement achieved for any Cepheid as of early 2008. The accuracy of the new measurement is important because Cepheids serve as a marker for distances within our galaxy and for nearby galaxies.

neufer wrote:

inertnet wrote: That's funny, NASA and Wikipedia say 21 million, the Messier catalog says 27
and many others say in between. So who's right?

• As of 13 September 2011: NASA & Wikipedia.

inertnet wrote:
That's funny, NASA and Wikipedia say 21 million, the Messier catalog says 27
and many others say in between. So who's right?

• As of 13 September 2011: NASA & Wikipedia.

https://en.wikipedia.org/wiki/SN_2011fe wrote:

[b][color=#0000FF]SN 2011fe: Best & Brightest of 4 M101 supernova[/color][/b]

---

<<SN 2011fe, initially designated PTF 11kly, was a Type Ia supernova discovered by the Palomar Transient Factory (PTF) survey on 24 August 2011 during an automated review of images of the Messier 101 from the nights of 22 and 23 August 2011. It was located in Messier 101, the Pinwheel Galaxy, 21 million light years (six megaparsecs) from Earth. It was observed by the PTF survey very near the beginning of its supernova event, when it was approximately 1 million times too dim to be visible to the naked eye. It is the youngest type Ia ever discovered. About 13 September 2011, it reached its maximum brightness of apparent magnitude +9.9 which equals an absolute magnitude of about -19 at six megaparsecs [-19 = +9.9 - 5log(6,000,000/10)]. This was the fourth supernova recorded in M101. The first, SN 1909A, was discovered by Max Wolf in January 1909 and reached magnitude 12.1. SN 1951H reached magnitude 17.5 in September 1951 and SN 1970G reached magnitude 11.5 in January 1970.>>

inertnet wrote:That's funny, NASA and Wikipedia say 21 million, the Messier catalog says 27 and many others say in between. So who's right?

Nitpicker wrote:

Ann wrote:Right, but M51 and M101 are not just any galaxies!

[sacrilege] Meh, not being much of a galaxy person, they're mainly just numbers to me. [/sacrilege]