Antares Lunar Graze - 4th October

[DaveGee]

On Saturday evening, 4th October at around 12:30 UT the moon will graze past Antares. Remember, that's the October long weekend!

As usual, there is a catch and this event is no different as the southern limit line runs from Port Lincoln in South Australia to near Cunnamulla in NSW. We'll have two teams operating, one north of Port Pirie and one north of Broken Hill. For your Google Mapping pleasure, I have created a Gmap and it's available here... http://users.tpg.com.au/users/daveg/occ_maps/081004_Antares.htm

The thin crescent moon will graze past Antares at a cusp angle of 15 degrees. Below is a moon map showing the situation. There will be little glare from the thin crescent and the ruby red Antares will a spectacular sight as it winks at the southern limb. The blue-green secondary might be seen on some reappearances (I need to check though). This event will probably be viewable with naked eyes although small binoculars will help. Personally, I'll have two video stations and a visual station operating.

I invite you to come along and join the Broken Hill team. Below is a Gsv (Google streetsview) of the site. As you can see, desert and flat are the operative words!

If you'd like to join the Broken Hill team, please advise. If you'd like to join the Port Pirie team, I can forward your details to the graze leader.

[Kevnool]

1 Question who,s involved with the Broken Hill team?....cheers Kev.

[DaveGee]

Hi Kev,

At the moment there are 4 observers coming from Sydney, and one from Canberra. I don't wish to name-names on a public forum without permission but suffice to say, I'm the contact here.:hi:

Do you wish to join the team? Our usual trick is to have a pre graze dinner (or post graze breakfast) somewhere. do you know a good eatery in BH?

[Kevnool]

If i,m in Broken Hill at the time i would be interested in hopping along to witness this.......as for the eaterys,s there all as much as much.....i,ll look into starry night to see this .........The site that you picked i hope its north of Broken Hill on the silver city highway( only because mine haul trucks go south 24hrs) but thats up to you.....if you need logistical support here then p.m me......cheers Kev.

[Kevnool]

Am i to understand that your going to packsaddle to observe only because i see it on your site?

[matt]

Will be too low to see here in Bris. Don't know how well you'll see it where you are?:whistle:

[SMR]

Gee! We never thought of checking simple things like that ... ;)

Don't worry, Matt. We know what we're doing. We've been planning this trip for months.

Steve.

[matt]

Gee!!! Sarcasm, no less.;)

Not trying to burst your bubble or suggest you don't now what you're doing. Rather, letting the good folk in these parts know how that's going to play out for us. It is...after all...posted where EVERYONE can see/read it:P

So...I just punched the co-ordinates for Broken Hill into Starry Night for this event ...and it shows the moon's very low (less than 10 degrees alt) for nearest approach.

Anyway...enjoy! Be sure to post the piccies. I hope to make a trip out that way one day with my scope.

[Dennis]

Thanks for the heads up Dave.:thumbsup:

Cheers

Dennis



Thanks for the Brisbane info Matt; you saved me the time looking it up.:thumbsup: It’s a pity we’re going to miss it.:(

Cheers

Dennis

[DaveGee]

Hi Kev,

Yes indeed, the southern limit line crosses the Silver City Highway near packsaddle. That's where we will observe the event with observers strung out at intervals of 150m or so.

Interestingly Antares will be have a measurable disk of about 90m diameter (as viewed from the Earth) as the moon grazes past.

PM me your email addy and I'll keep you in the direct email loop.

Dave

[DaveGee]

Hi Matt,

Yep, the moon and Antares will have set by graze time as viewed from Brisbane. Moonset at graze time is somewhere near Cunanulla.

At packsaddle (north of BH) the pair will be at 8 degrees altitude. At Port Pirie observers will have another 2 degrees altitude or so.

Below is a map of the complete path of the moon's shadow by the light of Antares as it sweeps over the earth. The red dotted line represents the event in daylight, the blue line represents the event in twilight and the white line represents the event at night.

Also attached is a text file. If you download that file and change the file type from .txt to .kml, you can load the file from within Google Earth.

[matt]

Cheers, Dave.

Hope you have a great time and skies are kind to you:)

[Kevnool]

Hi Dave on that weekend is a gymkana in Tibooburra so you may find the road a bit busy during the day, At hight you should be OK tho.

Thank goodness the section of road you chose is Bitumen, Mia from Packsaddle is a great lady and would help you if you needed a feed.

Are you camping out on the side of the road because packsaddle has only 3 rooms there for accomodation.

Hopefully i will be tagging along my fingers are crossed.

Cheers Kev.

[DaveGee]

Hi Kev,
thanks for the advice. No we are not camping. we are staying in various motels in BH and after the event will dodge the roos on the way back into town. I'll PM you with my mobile number.

Dave

[Kevnool]

I will be available to tag along with you guys to observe this event...look forward to meeting you all....cheers Kev.

[DaveGee]

Just to bring this thread up to date...

It looks like the Port Pirie end of the event is a non-starter. RIP

We now have an observing team that will observe north of Broken Hill, made up from 2 local observers and 6 blow-in observers, driving and flying in to BH from Sydney and Canberra. Most of the blow-ins will operate two or more stations, simultaneously or at the same time.:whistle:

Apart from obtaining good contours of the lunar limb, we hope to obtain measurements for the diameter of Antares and possibly observe limb darkening effects. The Antares disk will have a diameter of about 85m at the lunar limb (0.0438") so we hope to observe disappearance and reappearance events lasting perhaps 1 second or more.

Watch this space for the results of our endeavours. :thumbsup:

[DaveGee]

Well, we had a successful observation.
There were 8 observers operating 14 stations, all observing multiple events and most saw the reappearance of Antares B before the reappearance of Antares A, expecially on the final R event.

Present were...
DaveH - 2 video stations and 1 visual station
Darren - 1 video station
DaveG (me) - 1 video stations and 1 visual station
Hristo - 1 video stations and 1 visual station
Kev - 1 visual station
Trev - 1 visual station
Chris - 1 video stations and 1 visual station
Stephen - 1 video stations and 1 visual station

The analysis of our records is a work in progress but my video can be seen here...
http://au.youtube.com/watch?v=94Svkv8o74g
note the telescope was defocused to try and limit the effects of image saturation by spreading the light from Antares over many pixels.

and the light curve can be seen here...
http://users.tpg.com.au/users/daveg/lunarvideos/081004_AntaresGraze.png

again, watch this space...

[Dennis]

Hi Dave

Well done to you and the team. I enjoyed the video – great stuff. Seeing Antares blink on and off as if skipped along the lunar limb was quite breathtaking.

An excellent capture, showing complete mastery of your equipment, along with 1st class skills and technique.

Cheers

Dennis

[DobDobDob]

Continued great work Dave and team, you guys are certainly on the bleeding edge :thumbsup:

[seeker372011]

:bowdown::bowdown::bowdown:

[Quark]

Hi Dave,
Have just sent my data off to Dave, H.
Definitely picked the right night, Sunday night was dense 10/10 cloud with occasional showers. Enjoyed my first grazing occultation.

Regards
Trevor

[DaveGee]

I'm glad you enjoyed the event. Good luck with Keck. My offer still stands, if you need someone to carry your bags... pick me...:hi: