Amateur astronomy equipment, techniques, info, etc

Possible meteor shower tonight (gamma Delphinids) — CBET 3553

(I hope the CBAT will forgive me for posting this here.  Short story:

a meteor shower last seen in 1930 *may* recur tonight, around 8:30 UTC.

The Americas are favored.)

                                                   Electronic Telegram
No. 3553

Central Bureau for Astronomical Telegrams

INTERNATIONAL ASTRONOMICAL UNION

CBAT Director:  Daniel W. E. Green; Hoffman Lab 209; Harvard University;

  20 Oxford St.; Cambridge, MA  02138; U.S.A.

e-mail:  cbat…@eps.harvard.edu (alternate c…@iau.org)

URL http://www.cbat.eps.harvard.edu/index.html

Prepared using the Tamkin Foundation Computer Network

PREDICTED POSSIBLE OUTBURST OF GAMMA DELPHINID METEORS

      P. Jenniskens, SETI Institute; and E. Lyytinen, Helsinki, Finland,
predict

a return of the 1930 Gamma Delphinids meteor shower with a peak on 2013
June 11

at about 8h28m UT.  The shower is expected to last only about 30 min and

consist mainly of magnitude +2, +1, and 0 meteors.  The 1930 shower radiated

from R.A. = 313 deg, Decl. = +17 deg (equinox 2000.0); the meteors had short

trails of brief duration and were yellowish-white.  Meteor observers Paul S.

Watson, Frank Oertle, and Joseph Field of the American Meteor Society
recorded

51 meteors then under full-moon conditions — 39 of which were of
magnitude +1,

and 10 of which were of magnitude 0.  The shower only lasted 30 min.  This

account is interpreted as having been caused by the dust trail of a long-

period comet, which thus is an unknown potentially hazardous comet that
passed

close to earth’s orbit in the previous return from which dust now
streams past

the earth’s orbit.  If so, that stream of dust is predicted to move into the

earth’s path in 2013 — that is, if the radiant position of the meteors was

correctly recorded in 1930 (Lyytinen and Jenniskens 2003, Icarus 32, 51-53;

Jenniskens 2006, Meteor Showers and their Parent Comets,

pp. 194 and 617).

NOTE: These ‘Central Bureau Electronic Telegrams’ are sometimes

       superseded by text appearing later in the printed IAU Circulars.

                          (C) Copyright 2013 CBAT

2013 June 10                     (CBET 3553)              Daniel W. E. Green

.
Comments (18)

Re: Advice sought for setting up a Mead model 300 "equatorial refractor" telescope

In article <kp42ia$9i…@news.albasani.net>,

 "Angel A." <aan…@example.com> wrote:

> My kid inherited this apparently ancient Meade 3.1-inch equatorial refractor

> telescope, model 300, presumably in working order – but it doesn’t work for
> us:

>  http://www4.picturepush.com/photo/a/13283857/img/13283857.jpg

> We *think* we have all the parts; but we’re not sure.

>  http://www5.picturepush.com/photo/a/13283853/img/13283853.jpg

It looks reasonably complete, although in the first photo there’s no
eyepiece inserted. The other photo shows several of those in the box;
start with the lowest power you have, which will be the one with the
*biggest* number (focal length) etched on it, probably around 20-25 mm.
In case you hadn’t guessed, you focus with the paired metal knobs
between the "star diagonal" (the elbow below the eyepiece-holder) and
the main tube.

One critical element we can’t see is the objective lens at the ‘big
end’, probably near the bottom of the large black cylinder (which I
guess is a baffle): this should be clean and unscratched. If you need to
clean it, be *very* careful not to damage the surfaces, which may be
coated. Handle it only by the edges, and use the most gentle treatment
possible, with a soft brush or lens-cloth, and only distilled water or a
residue-free lens-cleaning fluid that’s safe for optical coatings.

Unless you live on the Equator, the first picture also has the ‘scope
improperly oriented (the polar axis, the short shaft that’s shown
roughly horizontal and parallel to the tube, should be elevated by an
angle equal to your latitude and locked there), but that makes no
difference to seeing things through it in the daytime.

> Do you know of a decent forum where we can discuss the parts, setup, and
> operation of this telescope for looking at the stars and moon?

Your best chance of finding someone with directly relevant experience or
practical tips will be at sci.astro.amateur. I’m taking the liberty of
cross-posting this message there as well. (And removing sci.astronomy,
which my news server doesn’t carry.)

> Note: We can’t even get the scope to work, at least not on the trees in the
> distance:
>  http://www3.picturepush.com/photo/a/13283856/img/13283856.jpg

This is the finder-scope, an accessory that helps point the instrument.
There should be screw-holes in the main tube for attaching it, near the
eyepiece end. It’s not strictly necessary, but can be useful, especially
when using medium-to-high power. Test it hand-held on the Moon: it might
not focus on anything nearer.


Odysseus

Comments (3)

Built before NASA was as shabby as it is now

http://www.bbc.co.uk/news/science-environment-22832673

No Comments

solstice/super full moon

The next full moon is close to the summer solstice.
The full moon will be June 23 at 9:02 a.m. NDT and
the solstice will be June 21 at 2:34 a.m. NDT.
Perhaps I will celebrate both on the night of

June 22, which is a Saturday.  Or an option is to
celebrate for three days straight. (I am neopagan,

though not Wiccan.)

June 23 (or moonset the night of June 22) will be a
super full moon. A friend shared this photo with me:

https://www.facebook.com/photo.php?fbid=200549416766562&set=a.1363451…

0324.30543.136336876521150&type=1&theater

The photo has text which says that:

"This year’s largest

and closest `Super Moon’ will occur on June 23, 2013.

This super full moon is not only the closest and largest

full moon of the year, it also presents the moon’s
closest encounter with Earth in a long time."

Again that full moon is at 9:02 a.m. NDT June 23,

or 4:32 a.m. PDT June 23 in Vancouver.   So the

closest visible moon to the exact time of full

moon here in St. John’s will be at moonset at

the end of the night of June 22, assuming it
isn’t cloudy then.   I will probably view it

on my way home from some friends’ place (where

I often am from midnight to 4 a.m. or so on

Saturday night/Sunday morning).


David Dalton  dal…@nfld.com   http://www.nfld.com/~dalton (home page)

http://www.nfld.com/~dalton/nf.html Newfoundland&Labrador Travel & Music

http://www.nfld.com/~dalton/dtales.html Salmon on the Thorns (mystic page)

   "Here I go again…back into the flame" (Sarah McLachlan)

Comments (2)

Ephemerides limitations

When Kepler studied the motion of Mars from the point of view of a

moving Earth there was no daily rotational element involved,it is a

straightforward plotting the orbital motion of Mars in tandem with the

orbital motion of the Earth -

http://upload.wikimedia.org/wikipedia/commons/e/e9/Kepler_Mars_retrog…

http://apod.nasa.gov/apod/ap100613.html

The motion of Mars against the background constellations do not

include any stellar circumpolar input which is inherent in the

equatorial coordinate system where the motions of celestial objects

move in a celestial sphere diorama generated by the daily rotation of

the Earth in a 365/366 day calendar format -

http://www.youtube.com/watch?v=oQZp0lEEpsc

The empiricist community, represented by the IAU in these matters,

fails to grasp the limitations of the Ra/Dec framework which allows

the convenience of predicting events such as eclipses and transits

based on the apparent motion of objects relative to each other within

a celestial sphere framework by virtue that the observations are not

geocentric but homocentric,something quite different.

The dismaying part is that while  the observational convenience for

predicting astronomical events is invaluable to impose it back on to

the Earth’s daily and orbital dynamics  is catastrophic for everything

else such as the relationship between planetary dynamics and

terrestrial effects or celestial structures such as the solar

system,its inclusion in galactic structure and the relationship of our

galaxies to all others.All these things are undone by loading

ephemerides with relevance that they just do not have.

No Comments

SkyandTelescope.com Weekly Bulletin for Friday, June, 14, 2013

- — -

> SkyandTelescope.com Weekly Bulletin

> News

> ========================================

> How to Toast a Planet

> —————————————-

> June 11, 2013 |  A new study suggests that close-in gas giants may heat up electrically like toaster coils plugged in to their host stars via the power lines of the stellar wind &mdash; explaning why the planets inflate.

> Read More at: http://www.skyandtelescope.com/community/skyblog/newsblog/how-to-toas…

> Was our Sun a Feisty Toddler?

> —————————————-

> June 12, 2013 |  Detailed observations of a young, nearby star are giving astronomers a chance to glimpse the Sun’s active youth.

> Read More at: http://www.skyandtelescope.com/community/skyblog/newsblog/Was-our-Sun…

> Surprise Variable Stars

> —————————————-

> June 12, 2013 |  Astronomers have discovered an unexpected class of variable stars in the open cluster NGC 3766. The stars are problematic for current theories of star behavior and raise perplexing questions about why the stars are variable at all.

> Read More at: http://www.skyandtelescope.com/community/skyblog/newsblog/Surprise-Va…

> New View of Nearest Galaxies

> —————————————-

> June 10, 2013 |  Spectacular high-resolution images released at the 222nd American Astronomical Society conference in Indianapolis reveal two of the Milky Way’s nearest galactic neighbors in a new light.

> Read More at: http://www.skyandtelescope.com/community/skyblog/newsblog/New-View-of…

> Observing

> ========================================

> Comet ISON Approaches

> —————————————-

> June 13, 2013 |  The "comet of the century" was stuck at 16th magnitude when it hid out for the summer. Still, good prospects remain for December.

> Read More at: http://www.skyandtelescope.com/community/skyblog/observingblog/Comet-…

> Tour June’s Sky by Eye and Ear!

> —————————————-

> May 31, 2013 |  Venus, Jupiter, and Mercury crowd together low in the west right after sunset, while Saturn is sandwiched high in the south between the constellations Libra and Virgo.

> Read More at: http://www.skyandtelescope.com/community/skyblog/observingblog/Tour-J…

> This Week’s Sky at a Glance

> ========================================

> This Week’s Sky at a Glance

> —————————————-

> June 14, 2013 |  Mercury descends to pass Venus in twilight. And the waxing Moon passes Spica, Saturn, and Antares.

> Read More at: http://www.skyandtelescope.com/letsgo/whatsuptonight/211247631.html

> Brand new!

> ========================================

> Mars Elevation Globe

> —————————————-

> https://www.shopatsky.com/product/mars-topography-globe/new-arrivals

> SaturnMoons App

> ========================================

> SaturnMoons App

> —————————————-

> https://itunes.apple.com/us/app/saturnmoons/id606938707?mt=8

> SkyWeek Plus App

> ========================================

> SkyWeek Plus App

> —————————————-

> https://itunes.apple.com/us/app/skyweek-plus/id541708339?mt=8

> Brand New!

> ========================================

> Beautiful Universe 2013

> —————————————-

> http://www.shopatsky.com/product/beautiful-universe-2013/new-arrivals

> Shop at Sky

> ========================================

> S&T Online Store

> —————————————-

> Visit ShopatSky.com to find the latest and greatest products for the astronomer in you!

> http://www.shopatsky.com/

> Home: http://www.skyandtelescope.com

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> distribution information please read our terms and conditions.

> Copyright 2013 Sky & Telescope Media LLC

No Comments

Greatest astronomical innovation

By far,the greatest innovation since the telescope is sequential

imaging or time lapse footage which allows genuine astronomers to

condense what are long term observations into easily manageable form.

It allows observers to ascertain two types of retrogrades with two

unique solutions although tied into a moving Earth sandwiched between

the inner and outer planets.

All it needs are people who can put them into the science curriculum

where students will enjoy this type of challenge.

Comments (4)

Possible meteor shower tonight (gamma Delphinids) — CBET 3553

(I hope the CBAT will forgive me for posting this here.  Short story:

a meteor shower last seen in 1930 *may* recur tonight, around 8:30 UTC.

The Americas are favored.)

                                                   Electronic Telegram
No. 3553

Central Bureau for Astronomical Telegrams

INTERNATIONAL ASTRONOMICAL UNION

CBAT Director:  Daniel W. E. Green; Hoffman Lab 209; Harvard University;

  20 Oxford St.; Cambridge, MA  02138; U.S.A.

e-mail:  cbat…@eps.harvard.edu (alternate c…@iau.org)

URL http://www.cbat.eps.harvard.edu/index.html

Prepared using the Tamkin Foundation Computer Network

PREDICTED POSSIBLE OUTBURST OF GAMMA DELPHINID METEORS

      P. Jenniskens, SETI Institute; and E. Lyytinen, Helsinki, Finland,
predict

a return of the 1930 Gamma Delphinids meteor shower with a peak on 2013
June 11

at about 8h28m UT.  The shower is expected to last only about 30 min and

consist mainly of magnitude +2, +1, and 0 meteors.  The 1930 shower radiated

from R.A. = 313 deg, Decl. = +17 deg (equinox 2000.0); the meteors had short

trails of brief duration and were yellowish-white.  Meteor observers Paul S.

Watson, Frank Oertle, and Joseph Field of the American Meteor Society
recorded

51 meteors then under full-moon conditions — 39 of which were of
magnitude +1,

and 10 of which were of magnitude 0.  The shower only lasted 30 min.  This

account is interpreted as having been caused by the dust trail of a long-

period comet, which thus is an unknown potentially hazardous comet that
passed

close to earth’s orbit in the previous return from which dust now
streams past

the earth’s orbit.  If so, that stream of dust is predicted to move into the

earth’s path in 2013 — that is, if the radiant position of the meteors was

correctly recorded in 1930 (Lyytinen and Jenniskens 2003, Icarus 32, 51-53;

Jenniskens 2006, Meteor Showers and their Parent Comets,

pp. 194 and 617).

NOTE: These ‘Central Bureau Electronic Telegrams’ are sometimes

       superseded by text appearing later in the printed IAU Circulars.

                          (C) Copyright 2013 CBAT

2013 June 10                     (CBET 3553)              Daniel W. E. Green

Comments (18)

Re: Advice sought for setting up a Mead model 300 "equatorial refractor" telescope

In article <kp42ia$9i…@news.albasani.net>,

 "Angel A." <aan…@example.com> wrote:

> My kid inherited this apparently ancient Meade 3.1-inch equatorial refractor

> telescope, model 300, presumably in working order – but it doesn’t work for
> us:

>  http://www4.picturepush.com/photo/a/13283857/img/13283857.jpg

> We *think* we have all the parts; but we’re not sure.

>  http://www5.picturepush.com/photo/a/13283853/img/13283853.jpg

It looks reasonably complete, although in the first photo there’s no
eyepiece inserted. The other photo shows several of those in the box;
start with the lowest power you have, which will be the one with the
*biggest* number (focal length) etched on it, probably around 20-25 mm.
In case you hadn’t guessed, you focus with the paired metal knobs
between the "star diagonal" (the elbow below the eyepiece-holder) and
the main tube.

One critical element we can’t see is the objective lens at the ‘big
end’, probably near the bottom of the large black cylinder (which I
guess is a baffle): this should be clean and unscratched. If you need to
clean it, be *very* careful not to damage the surfaces, which may be
coated. Handle it only by the edges, and use the most gentle treatment
possible, with a soft brush or lens-cloth, and only distilled water or a
residue-free lens-cleaning fluid that’s safe for optical coatings.

Unless you live on the Equator, the first picture also has the ‘scope
improperly oriented (the polar axis, the short shaft that’s shown
roughly horizontal and parallel to the tube, should be elevated by an
angle equal to your latitude and locked there), but that makes no
difference to seeing things through it in the daytime.

> Do you know of a decent forum where we can discuss the parts, setup, and
> operation of this telescope for looking at the stars and moon?

Your best chance of finding someone with directly relevant experience or
practical tips will be at sci.astro.amateur. I’m taking the liberty of
cross-posting this message there as well. (And removing sci.astronomy,
which my news server doesn’t carry.)

> Note: We can’t even get the scope to work, at least not on the trees in the
> distance:
>  http://www3.picturepush.com/photo/a/13283856/img/13283856.jpg

This is the finder-scope, an accessory that helps point the instrument.
There should be screw-holes in the main tube for attaching it, near the
eyepiece end. It’s not strictly necessary, but can be useful, especially
when using medium-to-high power. Test it hand-held on the Moon: it might
not focus on anything nearer.


Odysseus

Comments (3)

Built before NASA was as shabby as it is now

http://www.bbc.co.uk/news/science-environment-22832673

No Comments