have fun! And remember, even a small instrument can give endless satisfaction. Just keep digging on new things to aim it at. There are constantly new supernova explosions, moon transits over Jupiter, new comets, new celestial events of all kinds.

Another advice: keep a log file of your observations. As you watch an object, describe it to yourself (even speaking aloud if that doesn’t bother you), trying to capture all possible details. Observe from a dark site, cover yourself with plenty of clothing, and find a comfortable position. These are very important ingredients for a successful viewing!

Cheers,
T.
Cheers,
T.

Cheers,
U

Marlon, what do you mean ? The solar system is not going anywhere!

Cheers,
T.

Fortunately for uneducated ol’ me, the astronomers are curious too, so lots of people are taking lots of pictures and lots of spectra (in fact, I’m watching one of Henry’s fellow grad students take some data on it as I type this) and I look forward to them explaining it!

According to an IFA Hawaii web page of Henry Hsieh
“… main-belt comets … the MBCs present a distinct contrast with other periodic comets (the Jupiter-family and Halley-family comets, or JFCs and HFCs) which originate in the cold outer solar system in the Kuiper Belt or Oort Cloud … Unlike the JFCs and HFCs, the MBCs appear to have formed in the much warmer inner solar system … MBC orbits are comparatively much more circular (making solar heating effectively constant) … for the activation of MBCs … We hypothesize … excavating impacts from other asteroids that “dig up” buried (and thus preserved) ice, exposing it to the heat of the Sun …”.

According to a Joe Rao article on space.com,
“… Comet Holmes … is part of Jupiter’s “family” of comets – a group in which the far end of their respective orbits (aphelia) cluster around the orbit of Jupiter …”,
and
according to a CIW web page of Scott Sheppard
“… Jupiter Family comets … are believed to originate from the Kuiper Belt … Their orbits are controlled by Jupiter …”.

Even though the orbit of 17P/Holmes may not be circular enough for it to be a true Main Belt Comet,
since its perihelion is pretty far out (around 2 AU) it may be that it Hsieh’s hypothesis for “activation” …
“… excavating impacts from other asteroids that “dig up” buried (and thus preserved) ice, exposing it to the heat of the Sun …”
might indeed apply to the outburst of 17P/Holmes.

Tony Smith

According to a web page of Gary Kronk’s Cometography:
“… 17P/Holmes … was discovered [ in 1892 ] during an apparent outburst in brightness …[and]… experienced another outburst in brightness around January 16 [1893] … a telescope revealed a nucleus of magnitude 8 and a coma 41 arc seconds across … The comet steadily faded after the mid-January outburst …”.

Since in the 115 years ( roughly 115 / 7 = 16. … orbits of 17P/Holmes ) from 1892 to 2007 the comet has had no outburst,
maybe it might be reasonable to guess that it hits something
every 16 orbits,
and
from that (and a guess at its physical cross-section) maybe a density of asteroids could be calculated
and
that might be compared with what is known about the density of asteroids distributed between Jupiter’s orbit ( around 5 AU ) and the comet’s perihelion distance (about 2 AU, acccording to Kronk, which is outside the orbit of Mars ( around 1.5 AU) so the orbit of 17P/Homes might be considered to be within the Asteroid Belt ).

Tony Smith

Cheers,
T.

thank you for the quotes. Indeed, that comet is an interesting object to study!

I heard a report from a fellow visual amateur, Michele Scaffidi, who observed it yesterday with a 16″ scope. He described a bright yellow nucleus and a fainter roundish reddish outer halo. Must be very nice to look, unfortunately my dob is in the mountains and there’s no way I am going to travel there with a full moon, and thus only the comet in my observing agenda. Sure, a comet is nice, but… Gas prices are high!

Nibiru ??? What the hell ?

Kea, I am sure aliens can’t wait either. Imagine the conversations on category theory. You’d probably be the only one who could converse with them, using your graphs.

Cheers,
T.

Pointed binoculars to it and we could tell there was something weird in its appearance, since it looked extended. So, pointed the 150 mm Maksutov to it and it looked wonderful: bright starlike nucleus, with a large, extended coma.

Thanks to J. Rao (via T. Smith) for the extra dynamical information (i.e., the fact that it’s a Jupiter Family Comet; its period; the fact that it’s moving AWAY , etc.). Very interesting.

2007 is turing out to be an iteresting year for comets: McNaught in the begining of the year and Holems at the end of the year!