Starship Asterisk*

Anthony Barreiro wrote:
And what is the bright, slightly extended object that would make the upper left corner of a parallelogram with Comet Lemmon, NGC 362, and 47 Tuc? Is it just a bright foreground star?

http://en.wikipedia.org/wiki/Beta_Hydri wrote:

<<Beta Hydri (β Hyi, β Hydri) is a star in the southern circumpolar constellation of Hydrus. (Note that Hydrus is not the same as Hydra.) With an apparent visual magnitude of 2.8, this is the brightest star the constellation. Based upon parallax measurements the distance to this star is about 24.33 light-years.

This star has about 108% of the mass of the Sun and 181% of the Sun's radius, with more than three times the Sun's luminosity. The spectrum of this star matches a stellar classification of G2 IV, with the luminosity class of 'IV' indicating this is a subgiant star. As such, it is a slightly more evolved star than the Sun, with the supply at its core becoming exhausted. It is the nearest subgiant star to the Sun and one of the oldest stars in the solar neighborhood. This star bears some resemblance to what the Sun may look like in the far distant future, making it an object of interest to astronomers.

At around 150 BC, this star was two degrees away from the southern celestial pole. It is currently the nearest relatively bright star to the southern pole.

In 2002 Endl et al. inferred the possible presence of an unseen companion orbiting Beta Hydri as hinted by radial velocity linear trend with a periodicity exceeding 20 years. A substellar object with minimum mass of 4 Jupiter masses and orbital separation of roughly 8 AUs could explain the observed trend. If confirmed, it would be a true Jupiter-analogue, though 4 times more massive. So far no planetary/substellar object has been certainly detected. These results were not confirmed in CES and HARPS measurements published on the arXiv in 2012. Instead the long-term radial velocity variations may be caused by the star's magnetic cycle.>>

2013 could turn out to be a comet bonanza. No fewer than three of these long-tailed beauties are expected to brighten to naked eye visibility.

• C/2011 L4 PanSTARRS
• C/2012 F6 Lemmon
• C/2012 S1 ISON

Ann wrote:I like the colors and "textures" of this image!

The Small Magellanic Cloud is blue and loose. 47 Tuc is like a heap of salt, white in color, densest in the middle and with grains of salt spread around the main concentration. Note the smaller globular, NGC 362, to the (slightly lower) right of the Small Magellanic Cloud. This globular looks even more concentrated than 47 Tuc, yet still slightly grainy.

The comet looks like a drop of clear green liquid, leaving a trail of blue-gray smoke behind.

Beautiful!

Ann

C.Garrison.White wrote:I suggest that ALL photos to be displayed on NASA sites [Astronomy Picture of the Day]
have a number/letter grid. Ex: 1-10 across, A-K [no I] up-down.

Then pinpointing items for the viewer would be clearer than "near the left side";
especially if the item has no outstanding features. Ex: Comet @ B2.

Thank-you, Garrison