Mojave National Preserve Fall Star Party, Nov. 11th 2017

This fall’s Mojave National Preserve Star party is on Saturday November 11th, 2017. Make a weekend of it and come out earlier in the day to get some hiking in before the potluck meal Saturday evening. This is a good location for seeing desert tortoises, hares and there’s usually a few cows hanging around as well!

I saw this desert tortoise on the road to the campground in September of this year.
Desert hares are also pretty common around the campsite.
A few cows are still allowed to graze in the preserve.

The Mojave National Preserve is one of the darkest sky locations in Southern California and well worth a visit and we bring a good selection of telescopes to the star party.

Some of the telescopes at the last MNP Star Party. The covered eating/cooking area with benches and tables can be seen in the background.

This star party there will be a third quarter moon but it will not affect our dark skies as it doesn’t rise until 12:44 am. If you plan on attending please RSVP either on the  Event Facebook page or by Email.  The photo above was taken at the Spring 2017 star party. Hope to see you there.

Mojave National Preserve Star Party, Nov. 5th 2016

This fall’s Mojave National Preserve Star party on Saturday November 5th, 2016 at the Black Rock Canyon group campground will also be a party celebrating the 100th anniversary of the National Park Service. Come out early and get some hiking in before the potluck meal Saturday evening. The Mojave National Preserve is one of the darkest sky locations in Southern California and well worth a visit. This star party there will be a first quarter moon early in the evening until 9:45 pm so we get to see both a beautiful moon and then wonderful dark skies. If you plan on attending please RSVP either on the  Event Facebook page or by Email.  The photo above was taken at a prior star party. Hope to see you on Nov. 5th.

Animated gifs From Photos

I spent a fair amount of time creating this animated gif in Photoshop from a sequence of 17 photos taken during a Pasadena Roving Archers Saturday advanced class. The camera was on a monopod rather than a tripod and so there was slight movement from frame to frame which I corrected. To do this the 17 images were imported into Photoshop as layers, with the final image being the base layer and each layer was then aligned wrt the base layer by differencing the layer wrt to the base layer and then free transform moving the layer until the background tree trunk differenced to zero. With all the layers aligned the image was then cropped to remove the edge effects and a timeline created into which they were imported to create a giant animated image. The final Photoshop file was ~2GB for an image that is 5794 x 3866 pixels. A final smaller gif was then created a 1024 x 683 size with a web color pallet (256 colors) that was just 10 MB that I proceeded to upload to the archers Facebook page. At which point I discovered Facebook does not support animated gifs. After all that work I wanted to share the result and so I have resurrected this blog after a long absence!

Choosing a Private Archery Coach

As many of you know I have been the president of Pasadena Roving Archers, PRA for several years now and have been an archer for over 30 years, having started as a competitive archer in college in the UK. PRA has been offering public archery classes every Saturday morning since at least the 1970s. With the recent sustained surge of interest in archery there are an increasing number of people asking about private classes and instructors. Unfortunately with the increased interest in archery we are hearing of some less than qualified people posing as instructors. With that in mind here is a simple check list to consider:

What do you want out of the lessons? To be taught the basics of shooting or to move past that and choose a discipline. There are different types of bows for different styles of shooting and while the fundamentals are the same the details differ as you specialize. If you already know you want a particular style then find an instructor that teaches that style.

USA Archery has a series of instructor and coach certification classes ( the instructor database is not reliable in our experience – it’s new and still being updated/scrubbed). Ask your instructor to show you their certification from USA Archery and their current membership of either USA Archery or National Field Archery Association. A membership in at least one of these two organizations is required for the instructor certification to be valid.

There are various levels of certification with Level 1 being the most basic. For our classes at PRA we use only Level 2 or higher instructors and we have Level 1 assistants working under the supervision of a Level 2 or higher instructor. For private instruction I recommend seeking out at least a Level 2 instructor.

Verify that the instructor has insurance.

If the instructor wants to meet you at a public archery range, like the one in Pasadena ask to see proof that they have an agreement with the City in question to use the range for that purpose. Even as an all volunteer, non-profit organization PRA pays fees to the City of Pasadena for use of the range in Pasadena. Most cities want for-profit organizations to pay for the use of city facilities and if your instructor is trying to skate on that issue what does it say about them?

Different instructors have different styles. Talk to the instructor before hand and find out if they are going to work for you. For example, some people may like the ‘drill Sargent do as I say’ style of instruction while others may prefer a gentler more explanatory style of instruction.

If you want to do more than just ‘try-it’ then you will need several lessons – ask the instructor about packages of lessons and how you progress from lesson to lesson.

The instructor should provide all equipment. They should check for eye dominance to determine if you are going to shoot left or right handed before they give you a bow. The bow should be a light draw weight of 15-20lbs. If they offer you a heavier draw weight bow ‘like real archers use’ then run find someone else :)!

The instructor should provide a basic overview of safety rules before instruction starts.

Most importantly, enjoy yourself and have fun!

I’m sure I’ll think of something and add to this as necessary or as people send me comments.

Mojave National Preserve Star Party

As the opening post in resurrecting this blog I’d like to announce the Mojave National Preserve Star Party is scheduled for Saturday 26th October. This is a wonderful star party in one of the few truly dark sky locations left in Southern California. The banner photo for this blog was taken at that location. The star party is held in conjunction with the Mojave National Preserve Service Project. In the evening before dark there is a communal pot luck dinner before the star party gets under way. Free camping is provided  for Friday and Saturday night at the Black Canyon Group Site across the road from The Hole in the Wall Campground. It can be windy at this location and it could be hot or cold at this time of year so prepare appropriately.

Desert Tortoise

When you get there keep your eyes open during the day for the threatened Mojave desert tortoise, I’ve seen quite a few in the area over the years. It is unlawful to touch, harm, harass or collect wild desert tortoises so eyes and cameras only – if you alarm the tortoise it may loose water that it needs for survival so keep your distance!

As I type this I am assuming that the current government shutdown will end before October 26th otherwise the star party will have to be postponed or cancelled. Many of my friends and colleagues including Mojave National Preserve Rangers are furloughed while people in Washington posture over an artificially created crisis designed to make themselves look important!

Star Party has been postponed until November 30th – see you then

New Jupiter Impact

Earlier today Australian astronomer Anthony Wesley reported a new impact site on Jupiter just as the sun was rising at his location. His image can be seen on his webpage. The time stamp on the image is Universal Time (UT). Renowned amateur observer Christopher Go has also captured a short video of the event which can be viewed on his site. There has not yet been a confirmation that there are leftover signs of the impact but observers are gearing up to try. To do this we need to know when the impact site is visible, according to Christopher Go the event occured at longitude 343 (System II). With this information we can calculate future observation opportunities:

6/4 5:04 15:00
6/5 0:56 10:52 20:47
6/6 6:43 16:39
6/7 2:35 12:30

All of the times in the table are transit times (UT). Practically the impact site is visible for a couple of hours on either side of the listed times. Unfortunately this does not work out well for viewing from my location in California – the time here is UT-7 hours so this gives the following local times for the transit:

6/3 10:04pm
6/4 8:00am 5:56pm
6/5 3:52am 1:47pm 11:43pm
6/6 9:39am 7:35pm
6/7 5:30am

The first opportunity at 10:04pm tonight (6/3) will not work because although the event is facing us Jupiter does not rise until 2 am and so is below the horizon! The following morning (6/4) the impact site will be visible from ~6am onwards and Jupiter will be high in the sky but the sun will have risen and be too bright. The first real chance is not until the morning of 6/5 from ~2am onwards as Jupiter is rising. This may be too long after the event for anything to continue to be visible.

Sky Fever

For various reasons it’s been too long since I was out observing under a good dark sky. John Masefield’s poem “Sea Fever” came to mind and so without further ado, my butchered version:

Sky Fever
I must go out to the dark sky, to the Milky Way in the sky,
And all I ask is a tall ‘scope and a star to steer her by,
With observers lists and a red light and coffee by the pint,
For a long night at the eyepiece until the grey dawn breaking.
I must go out to the dark sky, for the call of the nebulae
Is a wild call and a clear call that may not be denied;
And all I ask is an inky night with the deep sky calling,
And the dark lanes and the bright stars, and the clusters gleaming.
I must go out to the dark sky, to the vagrant observers life,
To the snake’s home and the coyote’s home where the day sun’s like an oven;
And all I ask is a merry yarn from a laughing fellow-rover,
And quiet sleep and a sweet dream when the long nights over.

With Apologies to John Masefield

Station Fire Moon

Over the last few days thousands of photos of the Station fire have been posted on the internet by many people. I have myself posted photos to Facebook of the fire that burned behind JPL on Friday night and some of these have been picked up and reposted elsewhere by others.

Astronomers have been hearing about the imminent danger that Mt. Wilson has been in and every night for the past few nights I have periodically stepped outside into my back yard and peered up to see if the antenna towers are still visible. Usually the peak has been swathed in clouds of smoke completely invisible from Pasadena but tonight when I stepped out they were still visible. The moon, shown in the photo I took this evening, was also up and is a bright orange, typically only seen during an eclipse and referred to as a blood moon by some cultures. These days we know that the orange colour we see tonight is due to light scattering from the large amounts of smoke and ash in the atmosphere that have been catching at our throats for the past few days but historically a blood moon was thought to foretell coming disaster and destruction.

Tonight is expected to be the night when the fire will make it’s assault on the historic observatory on Mt. Wilson. The weather today has been much better for fighting the fire and the defences on Mt. Wilson have been buttressed as much as possible during the day. A good account of the measures taken can be found on the Los Angeles Time L.A. Now blog. However as I look up at the mountain and then at tonight’s blood moon I can’t help but shiver. On this night our hopes and prayers are with the fire fighters that have remained on the mountain overnight to defend our history.

Mars Hoax

It’s the time of year when the ‘Mars as big as the moon’ hoax will be doing the rounds. The Old Town Sidewalk Astronomers have been combating this myth since 2005. The composite image above has two images of Mars pasted to the left of the moon – the images were taken by myself and are at the same scale. The large image is the size Mars was during it’s close approach to Earth in August 2003. The small image is the size Mars was in June/July of this year – a close approach occurs every 15-17 years. Mars is never any bigger than it is shown here ie it is never the size of the moon.

There is more information about Mars and the Mars hoax on the Old Town Astronomers website

Jupiter Impact Update

The Old Town Sidewalk Astronomers had some excellent views of Jupiter Saturday night through my 8 in SCT and Jane’s 7 in refractor. The impact site was clearly distinguishable and we watched it rotate across the disk. We finished the evening with a quick look at the other blue planet, Neptune.

I’ve had a number of requests about future times for viewing the impact site. Here are the best transit times from tonight onwards for Pacific Summer Time – remember the site is visible for about 1 1/2 hours either side of these times.

7/28/2009 1:33 AM
7/30/2009 3:11 AM and 11:03 PM
8/1/2009 4:49 AM
8/2/2009 0:40 AM
8/4/2009 2:18 AM and 10:10 PM
8/6/2009 3:56 AM and 11:48 PM

All times calculated using the excellent Astromist application for PDAs available from