Occultation of Regulus: How Often and Why?

[Maria76]

Hi,

I saw the occultation of the star Regulus by the Moon 2 years ago (June 2007). I wonder how often this event happens, and why?

Thank you for your time.

Maria

 

[Nan]

Hi Maria,

Occultations are fun. You may find this resource helpful: http://www.occultations.net/index.htm" Sometimes it is painful waiting for an event and then the 'nail-biter' of if the astronomy gods are happy with you and provide you with clear skies. ;-) For NA, Regulus (IIRC) is a relatively rare event (but I could be wrong).

For me it was watching Mercury transit the sun in the '90s, then awaiting the once in a lifetime Venus transit in June 2004. I greatly anticipated that event and prepared for it. As I live far north, it was uncertain if fog or other elements might obstruct it as it would be early morning here for the event. What joy when it occurred and visible. NECESSARY DISCLAIMER: *never/EVER view the sun without the proper equipment and experienced observers*

I hope this helps, your location will determine if you are able to view particular occultations.

Edit to include: http://www.rasc.ca/publications/index.shtml" This handbook was always at my side to plan observing events. There are others out there of course. If you belong to an astronomy association, sometimes discounts are available. It will provide you with the events, including occultations for the entire year. Its a wonderful resource overall for observational astronomy.

 

[Maria76]

Hi Nan,

I was also looking forward to the 2004 Venus transit, but unfortunately the weather conditions conspired against me :(

In my question, I was really wanting to know how we can predict the lunar occultations of Regulus. I don't believe these events are rare (although I could be wrong about that), and the timing may change due to precession of the moon's orbit.

Cheers,
Maria

 

[Nan]

Oh that's awful! I'm so sorry you missed the Venus transit. I got to say, even though I was up all night observing the night before, I got so pumped that I couldn't go to sleep until it got dark again. ha. Good thing I'm an insomniac.

Your question is beyond the scope of my understanding/abilities It is of course relationship of our orbit, the moons orbit, your location and a whole lot of geometry, trig, etc. for Regulus and other occultations. Just like with lunar eclipses and solar eclipses; it may be visible to another part of the world, but at your location, you won't be able to.

I am always awed by those who perform the calculations for events like that. Those narrow windows for launches and getting an object out to another planet are amazing and seem like alchemy to me.

Here is a nice website that will provide you with bright star occultations in NA major cities:
http://www.lunar-occultations.com/bobgraze/index.html"

This is an outstanding resource and provides software for predictions of events:http://www.lunar-occultations.com/iota/iotandx.htm" A little browsing there may provide the answers you are seeking, or perhaps someone more skilled than I am here will.

I note there will be an occultation of the Pleiades visible in NA later this year! Dat will be kewl. Do you perform timing when you observe occultations?

I'm sorry I'm not able to shed light on your question.

 

[tony873004]

...then awaiting the once in a lifetime Venus transit in June 2004...

Twice in a lifetime. Venus again transits the Sun on June 6, 2012.
http://en.wikipedia.org/wiki/Transit_of_Venus,_2012

 

[turbo]

Here you go! Curt is a heck of a nice guy and he keeps his website updated with upcoming occultations, lunar limb grazes and other interesting phenomena, along with maps showing where and when they will be visible.

http://www.curtrenz.com/astronomical.html

 

[Nan]

Twice in a lifetime. Venus again transits the Sun on June 6, 2012.
http://en.wikipedia.org/wiki/Transit_of_Venus,_2012

You are wicked! I didn't know this! Now I got to check it out. I've been out of observational astronomy for awhile because of some limitations but just DANG! I hope I'm not too far north (and still breathing air in 2012). Where did I get the idea it was just once every 80 or so years? Big ooops for me and my apologies.

 

[tony873004]

Where are you located? Looking at the map, there doesn't seem to be such thing as "too far north" for this transit. June is the northern hemisphere's summer. The farther north you are, the longer the sun is up. And that's the only condition you must fulfill. The sun must be up while the transit is taking place. BTW, this transit is only 17 days after the Moon transits the Sun, which is also favorable for northern latitudes. This eclipse will be annular for Northern California, and partial for all American and Asian latitudes up to the north pole (so you're probably not too far north for this one). Your solar filter will be put to good use during these couple of weeks.

 

[Nan]

Where are you located? Looking at the map, there doesn't seem to be such thing as "too far north" for this transit. June is the northern hemisphere's summer. The farther north you are, the longer the sun is up. And that's the only condition you must fulfill. The sun must be up while the transit is taking place. BTW, this transit is only 17 days after the Moon transits the Sun, which is also favorable for northern latitudes. This eclipse will be annular for Northern California, and partial for all American and Asian latitudes up to the north pole (so you're probably not too far north for this one). Your solar filter will be put to good use during these couple of weeks.

Well now I have my excuse not to sell my gear. I've been putting it off because I have so many wonderful memories attached and I just couldn't bring myself to do it. I'm in the Northern Green Mtns of Vermont, so looks like I'm in luck (if the astronomy gods will be kind to me once more with clear skies). I made a stopped down mylar for my 8" SCT for the Venus transit and I also had a full filter for the 90mm mak which I used for the Mercury transit in the '90s. The best view I got though was through a friend's wonderful 6" homemade dob. (mirror too).

Thank you very much!