Jan 20/21/22/23/24/25 Meteors

Since I restarted my video meteor survey last month, I have been able to record meteors on 31 consecutive nights. That streak came to an end on the night of Jan 24/25 when the first storm in many weeks affected Arizona. To call it a storm might be giving it too much credit as it only brought a few sprinkles overnight and no measurable rainfall to the Tucson area (closer to the AZ/Mexico border a few hundredths of an inch were recorded).

When the clouds aren’t in the way, at least 20-30 meteors per night are being detected. None of the active showers are major meteor producers but a few of the minor ones are actively producing.

Obs  Date(UT)      Time    TOT SPO ANT COM NCC GUM ECV JCO
SAL  2014-01-25   00h 00m   *****  CLOUDS ALL NIGHT *****
SAL  2014-01-24   06h 55m   2   2   0   0   0   0   0   0
SAL  2014-01-23   11h 53m   27  18  1   1   1   2   2   2
SAL  2014-01-22   05h 22m   8   5   3   0   0   0   0   0
SAL  2014-01-21   11h 48m   29  23  1   1   1   0   2   1

SAL - SALSA3 camera in Tucson (Carl Hergenrother)
VIS - Visual observations from Tucson (Carl Hergenrother)
Time - Total amount of time each camera looked for meteors
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
ANT - Antihelions
COM - Coma Berenicids
GUM - Gamma Ursae Minorids
NCC - Northern Delta Cancrids
ECV - Eta Corvids
JCO - January Comae Berenicids

Jan 18/19/20 Meteors

The meteor year can be divided in two, a half with low meteor activity and one with high activity. The transition between high and low activity usually takes place in mid to late January and extends into June. Still rates seem to be holding up fairly well though we may see only half as many detections by the time February starts.

Obs  Date(UT)      Time    TOT SPO ANT COM NCC XUM GUM ECV
SAL  2014-01-20   12h 22m   22  20  1   0   0   0   1   0
SAL  2014-01-19   12h 19m   23  20  0   1   0   2   0   

SAL - SALSA3 camera in Tucson (Carl Hergenrother)
VIS - Visual observations from Tucson (Carl Hergenrother)
Time - Total amount of time each camera looked for meteors
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
ANT - Antihelions
COM - Coma Berenicids
GUM - Gamma Ursae Minorids
NCC - Northern Delta Cancrids
XUM - January Xi Ursae Majorids
ECV - Eta Corvids

Bright Stars in the Sky

Though this blog mainly focuses on comets, asteroids and meteors, the blog postings which seem to get the most hits are those referring to bright stars visible in the sky. This shouldn’t be too surprising since the most frequent (and often times most obvious) sites in the sky are bright stars low near the horizon during the hours most people are out and about (just after sunset and right before sunrise).

This post will provide a quick sweep of the early evening and early morning sky to highlight some of the brighter objects in the sky.

EVENING:

Most of the bright star action as soon as it gets dark in the evening is located in the southeastern sky. Not only do we have the usual Winter Sky suspects, but Jupiter joins them this year. Located in the middle of Gemini to the right of the pair of bright Gemini stars, Castor and Pollux, Jupiter outshines every star and planet in the evening sky. A few recent high-resolution images of Jupiter can be seen in this post.

The brightest star in the sky (though still half the  brightness of Jupiter) is Sirius. This time of the year Sirius gets a lot of attention because of its location close to the horizon near sunset. When so low Sirius may appear to not only change brightness but also to vary in color if the air is turbulent.

Night sky for northern mid-latitudes around 6:45 pm. Chart created with Stellarium. Credit: Carl Hergenrother.
Night sky for northern mid-latitudes around 6:45 pm. Chart created with Stellarium. Credit: Carl Hergenrother.

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Sirius is a blue star but can appear to change color rapidly. The reason for this is due to the Earth‘s atmosphere. Turbulence in the atmosphere causes the star’s light to be “bounced” all over the place. The light of the star is made up of many different colors which all “bounce” around differently. As a result, normally blue Sirius can appear to rapidly switch between many different colors when it is close to the horizon (meaning its light is passing through more atmosphere than usual). All stars experience this effect, it is just that Sirius‘ brightness makes it more evident. Watching Sirius when low in the sky with a telescope or just your eyes can be one of the best sights in the night sky.

Why does Sirius twinkle and change colors while brighter Jupiter does not? Check out Phil Plait’s explanation on his Bad Astronomy site.

More on Sirius can be found here.

MORNING

Some early risers may notice brilliant Venus low in the southeast. Only a few weeks ago Venus was a brilliant evening object in the southwest right after sunset. After passing roughly between the Earth and Sun, the brightest planet is now beginning a long stint as the ‘Queen of the Morning Sky’.

View of the early morning eastern sky from northern mid-latitudes around 6:35 am. Chart created with Stellarium. Credit: Carl Hergenrother.
View of the early morning eastern sky from northern mid-latitudes around 6:35 am. Chart created with Stellarium. Credit: Carl Hergenrother.

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Before leaving the morning sky, Robert Lunsford was able to image Venus through his 9.25″ telescope. At that time the planet was a very slender crescent. Venus shows a similar phase at this time as well.

Image of Venus taken by Robert Lunsford from ChulaVista, CA on 2013 January 6 with a C9.25 telescope. Credit: Robert Lunsford.
Image of Venus taken by Robert Lunsford from ChulaVista, CA on 2013 January 6 with a C9.25 telescope. Credit: Robert Lunsford.

Jan 16/17/18 Meteors

A steady shower of meteors continues to fall on Tucson, night after night. Even with a still very bright Moon, the cloud-less sky is allowing almost two dozen meteors to be detected nightly.

Last night, the best meteor was the one shown below. Occurring at around 9:11 UT, it was extremely slow (taking 3.8 seconds to move ~30+°) and bright (magnitude ~-1). The stars that it passes by in the lower left of the frame are the bowl of the Big Dipper. The bright thing just outside the upper right edge of the FOV (and causing the oval reflections near the top and bottom) is the Moon.

2014jan18_091147

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Though unrelated to the meteor above, four other meteors appeared to radiate from a point just to the southeast of the Beehive (M44) in Cancer. It is possible that these meteors are related to the Northern Delta Cancrids (NCC) even though the MetRec software only attributed one to that shower (the other four were assigned to the Antihelion (ANT) region which is very close as well).

2014Jan18_metrec_plot
Radiant plot showing the near-opposition sky on the night of 2014 January 18 UT from the SALSA3 camera in Tucson, Arizona, USA. Credit: Carl Hergenrother.

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Obs  Date(UT)      Time    TOT SPO ANT COM DLM NCC XCB XUM GUM
SAL  2014-01-18   13h 47m   25  16  5   3   0   1   0   0
SAL  2014-01-17   11h 59m   21  17  0   0   2   1   1   0   0

SAL - SALSA3 camera in Tucson (Carl Hergenrother)
VIS - Visual observations from Tucson (Carl Hergenrother)
Time - Total amount of time each camera looked for meteors
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
ANT - Antihelions
COM - Coma Berenicids
DLM - December Leonis Minorids
GUM - Gamma Ursae Minorids
NCC - Northern Delta Cancrids
XCB - Xi Coronae Borealids
XUM - January Xi Ursae Majorids

Jan 14/15/16 Meteors

The Moon is close to Full these days which is not helping with meteor detection. Still the nightly numbers of detections is similar to those of the past week so maybe the Moon isn’t being as big of a bother as expected.

Over the past three nights, the Earth was passing close to the orbit of now defunct comet C/2012 S1 (ISON). Only a single possibleISONid‘ was detected and the important word is ‘possible‘. The comet passed through this part of its orbit around 74 days ago so it is unlikely that much dust should still be in this part of its orbit. In future years, it is very possible that the dust will become more spread out (due to differences in their orbital period which do to various effects will be substantially smaller than that of the main comet) and a annual, though weak, ISONid shower will be visible.

Obs  Date(UT)      Time    TOT SPO ANT COM DLM NCC XCB ISO
SAL  2014-01-16   11h 48m   23  15  3   2   2   0   0   0
SAL  2014-01-15   12h 11m   18  10  5   0   2   0   0   1

SAL - SALSA3 camera in Tucson (Carl Hergenrother)
VIS - Visual observations from Tucson (Carl Hergenrother)
Time - Total amount of time each camera looked for meteors
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
ANT - Antihelions
COM - Coma Berenicids
DLM - December Leonis Minorids
ISO - ISONids
NCC - Northern Delta Cancrids
XCB - Xi Coronae Borealids
XUM - January Xi Ursae Majorids