Jane Houston Jones » moon

What’s Up in 2013 at a glance

jane — Mon, 07 Jan 2013 18:29:31 +0000

All year long, astronomers have been writing about Comet ISON: will it sizzle or will it fizzle? Both! Here’s my What’s Up video, with December status (written in mid November, but luckily, the comet didn’t completely fizzle)

ISON in December 2013

Comet ISON first spotted by amateur astronomer Bruce Gary and has been imaged by many eagle-eyed observers with good astrophotography equipment since mid August. A selection of images and data are shown here. I’ll update this frequently as more is understood about Comet ISON. Meanwhile, here is a wesbite with current Comet ISON magnitude and location which is constantly updated!

Comet ISON survived its close pass of the sun on November 28. Scientists are unsure what is actually left of the comet. A fragmented nucleus? Nothing but orbiting dust? Stay tuned!

Here’s an excellent Star Chart showing Comet ISON’s path in November, courtesy of Skyhound’s Skytools3 software. (These are the charts I use for my own deep sky observing.) The chart has not been updated for December as of November 30th.

Latest visible comet news here.

December 2013

You may have noticed a very bright ‘star’ in the western sky. That’s Venus! Venus shines at its very brightest, magnitude -4.9 this month. It sets about three hours after sunset at the beginning of the month and one and a half hours after sunset at the end of the month. This is a great month to view the dramatic changes in the apparent diameter and phases of Venus as it races towards its conjunction with the sun. The first observations of the phases of Venus were made by Galileo in 1610!

Mars continues to grow brighter and rises near midnight, and Jupiter rises earlier in the evening, heralding the best viewing season for Jupiter watchers.

The beautiful Geminid meteor shower will only slightly be marred by moonlight on the night of December 13 and 14. The radiant lies near Gemini with brilliant Jupiter above and the constellation Orion below. From a dark sky, but even from the city, the mighty hunter Orion is easily visible in the southeast sky. Take a look at Orion’s shoulder star, red Betelgeuse and its knee star, blue Rigel and the Orion Nebula.southwestern horizon.

The Milky Way and all the visible planets and comets should encourage stargazers to escape the city lights this month. Join me in the California Desert November 30, at MOjave National Preserve. We have no chance to See ISON for another week, but there are other nice comets, planets, stars, and dark sky objects too enjoy from dusk to dawn.

The times to look will be just after dusk, low to the horizon at sunset, and higher at dawn for northern latitudes the first half of the month. On December 1, look for a pretty diagonal lineup of the comet, Mercury and the crescent moon just before sunrise in the southeast. Then for the second half of the month, the comet becomes circumpolar. It will appear near the constellation Draco on December 26th, when it is half an a.u. (0.42 a.u.to be exact) from Earth. Will the comets’ tail span a quarter of the sky? I’ll update this as more info is available.

Jupiter reaches opposition January 4th, 2014, and rises earlier in the evening. Venus bright as it ever gets – a whopping magnitude -4.9. It will be a fabulous view – a particularly good astrophoto and sketching target as it grows in diameter, but shrinks in phase. Mars increases in brightness and rises earlier (after midnight). Mars will be a great target for 2014.

That’s all for this year, I’m Jane Houston Jones

Venus kissed the moon – a daytime occultation of Venus

jane — Sat, 18 Aug 2012 21:41:26 +0000

going

gone!

Venus reappears!

If you were up before sunrise on Monday, August 13th, 2012 you might have seen a very bright “star” next to the moon. As dawn turned to daylight, you could still see that star, or rather, that planet in the daytime snuggled up to the crescent moon.

That planet was Venus, and the moon was about to pass directly in front of it as seen from our vantage point on Earth. An occultation occurs when a solar system body passes in front of a more distant one or a star. Each one is only visible from a certain part of Earth. This occultation of Venus by the moon was only visible over northern Asia and Japan at night and over North America during the daytime.

I set an alarm to remind myself to step outside at about noon on Monday. It was a challenge to find the slender crescent moon, but I had a great view, shielded from the sun by the tall wall of my office building. The shadow helped by boosting the viewing contrast a little, too!

I had no difficulty seeing Venus naked-eye. And for about an hour I held court on the steps to JPL’s famed Space Flight Operations Facility or SFOF for short, and showed a daytime planet to several dozen of my colleagues. At about 1:30 p.m. PDT the moon passed in front of Venus after inching closer for over a half hour.

I was reminded of folksinger Christine Lavin’s lovely song Venus Kissed the Moon from her 1990 album Attainable Love. The lyrics go like this:

Venus kissed the Moon tonight
We watched her in the Sky
She’s been flirtin’ with him for centuries
Too bad he’s so shy
He’s waxing
He’s waning
You don’t see Venus complaining
She’ll steal a kiss whenever she can
Not ’till 2031
Will this happen again

There have actually been several Venus/Moon occultations since Christine wrote this song, but that doesn’t matter. I hummed her sweet song, and watched Venus flirt closer and closer to the moon. I’m listening to it as I write these words, too!

My friend Akkana Peck wrote “If you’ve never seen a Venus occultation before, you’ll be amazed at the difference between the brightness of Venus and the dimness of the moon’s limb. We think of the moon as bright, but it’s actually dark grey, about the same albedo (reflectivity) as asphalt; whereas Venus is covered with brightly reflective clouds.” See Akkana’s images of the Venus occultation and her blog here.

I snapped a few pictures with my hand-held Canon PowerShot SX260 HS with its nifty 20x zoom. I zoomed nearly all the way out for these images.

The next opportunity to see a lunar occultation of Venus from North and Central America will be on December 7, 2015. From Los Angeles, we’ll get to see this event from 7:30 am to 11:30 am.

I’m so glad we don’t have to wait until 2031 to see Venus kiss the moon, Christine!

A warm-up act for the Perseids

jane — Wed, 11 Aug 2010 06:22:56 +0000

See the moon and planets low in the west August 12, courtesy NASA/JPL-Caltech

The view from Earth - the planetary lineup in orbital perspective courtesy NASA's Solar System Simulator, courtesy NASA/JPL-Caltech

Mars and moon imaged same day with same equipment (in 2005) courtesy Jim Keen

A trio of planets, without the moon August 7, 2010, courtesy Morris Jones

Are you eager to see the annual Perseids on Thursday night? You’ll have to wait until after 10:00 p.m. local time to see them, so why not pass the time until showtime by viewing the planets right from your doorstep? Step outside for the planetary warm-up act.

All you have to do is look towards the west as soon as the sun sets. Bright Venus is the first to appear. It’s really bright, and you can’t miss it! Now, hold your clenched fist up to the sky covering Venus. To the right of Venus, about 1/2 of a clenched fist away is a second planet. That’s Saturn. And to the upper left of Venus is another planet… That’s Mars.

But wait, there’s more! Look below Venus for the slender crescent moon. If you don’t see the moon, look again Friday night – it will be a larger crescent to the left of Venus a day later.

Though the three planets appear together in our line-of-sight they are really far apart from each other and from us on Earth. Mars is about 300 million km (186 million miles) from Earth, while Venus is 112 million km/70 million miles distant. Saturn? It’s 1,535 million km/954 million miles from Earth right now. The moon? 363 thousand km, or only 225 thousand miles away. It’s fun to compare the size of the moon and Mars, especially if you received that annual email (which incorrectly) states that Mars will be as big as the moon this month. Do the math. It’s impossible!

The Solar System Simulator is a great public resource for geeks. You can see any planet or spacecraft from any vantage point on any date you select. I picked August 12th to show the view of the planets and moon from Earth.

I hope you can sense the three-dimensional orbits of nearby Venus, far-away Mars and distant Saturn. Have some fun with it! Every day the Cassini Mission website shows a view of Saturn from Earth, from Cassini, and right now Enceladus, as we close in on a flyby of that exciting moon later this week.

In this image of the moon and Mars, Jim Keen made a “true-to-life” size comparison. He made a “blended” image of the Moon and Mars back in July 2005. He recalls, “I had set up my telescope in my backyard and stuck a camera on the back of it. I took separate images of the Moon and Mars – both of which were “up”, but in separate areas of the sky – and later combined the two images to get one, showing the actual size difference using the same equipment, same camera, same magnification, and taken within a few minutes of each other.”

Jim’s image shows the apparent size of the moon and Mars really nicely! If he took the same image this month, Mars would appear super tiny! In the 2005 image Mars was about 50 million miles from Earth, and today it is 186 million miles away.

The final image shows the trio of planets imaged Saturday night August 7th by my hubby, Morris (aka Mojo) Jones. Click on the image to see the two fainter planets above Venus. He posted several images in his blog post called Sky full of planets and lightning. It’s really worth a read! The lightning was amazing Saturday night!

I hope this little planetary warm up act will whet your appetite for more sky watching this week. The Perseids will be a real spectacle, especially if you can get away from the city lights. I’ve pretty much decided to head out to the Mojave desert and see the star show from Amboy Crater. Clear Skies everyone, and happy solar system observing to you all!

California Clear Sky Chart Black dots indicate the darkest observing areas. Amboy Crater, on the southern border of Mojave National Preserve is the closest “black dot” dark observing area and will require a drive of over 200 miles for Thursday’s Perseids.

NASA’s Solar System Simulator Check out where the Voyagers are right now!

My Mars in August website, updated each year since 2005.

Halloween Sidewalk Astronomy – Tradition!

jane — Mon, 02 Nov 2009 06:14:51 +0000

Hauling a telescope across the streets of San Francisco

Jane-Orion plus Canis Major and Canis Minor

Mojo demonstrating where to find Jupiter's moons

Getting some eye candy

Sidewalk Astronomers have been setting up telescopes on Halloween as long as there have been sidewalk astronomers!

When we lived in the San Francisco Bay Area, we’d cross the Golden Gate Bridge from home and head to the Castro District of San Francisco on Halloween. It was crazy! Tens or maybe hundreds of thousands of revelers flock to the Castro on Halloween but I think we were the only ones with telescopes!

That Halloween sidewalk astronomy tradition continues in San Francisco to this day. And now that we live in southern California we’re carrying on the tradition in our new home town.

On Halloween, everyone with a telescope becomes a sidewalk astronomer. If there is a clear sky and a moon or planet to see, telescopes appear in front yards around the world. Astronomers love sharing the views, and a captive audience makes front yard astronomy a lot of fun for everyone.

The magic of sidewalk astronomy took over Library Park in Monrovia,CA minutes after we arrived. On this Halloween night, our club had 5 telescopes set up. Soon, princesses, superheroes and zombies alike said wow at our eyepieces! People stayed and looked through the telescopes for a long time. Even groups of teens, on their way to some event stopped for a look at Jupiter and the moon. They said wow too!

When I told one group of teenage girls that I didn’t have candy, but had bookmarks instead, one girl said “I love reading”. Every girl wanted their own bookmark. Later, a young boy, when he received a picture of Jupiter said “I am putting this picture on the wall in my room”.

Sharing views of the moon and planets on Halloween is a great tradition. Pass it on!

our club, the Old Town Sidewalk Astronomers

Photo Album from our Sidewalk Astronomy Halloween weekend October 30-31, 2009

A spooky list of telescope targets. Look if you dare!

LCROSS impact in crater Cabeus October 09 2009

jane — Mon, 12 Oct 2009 01:38:28 +0000

Rough sketch of LCROSS impact area

finished sketch of Cabeus and environs

E. A. Whitaker 1954 sketch

Mojo and I started to setup his 14.5-inch f/4.8 Litebox reflector at 3:30 a.m. on LCROSS impact morning. There were marine layer clouds at that hour, but by the time we were set up it was clear overhead. Friends deeper in the LA basin were fogged out completely!

I thought the seeing was not too bad — I was expecting a lot worse. I was able to use pretty high magnification — a 6mm Televue Radian which magnified the view 276 times. I increased the power to 446X using a 4mm Televue Radian, but that was a little too much magnification for the seeing conditions. My first “signpost” to Cabeus was the beautiful walled plain Clavius, with its semi-circle of craterlets on the floor. Two big craters called Rutherford and Porter, named for famous American astronomers, are on the wall of Clavius. There was no shadow relief, making the whole crater nearly invisible.

Then I crater hopped to Moretus, Short, Newton and finally Cabeus. Little bumps on the limb made the crater ID easy, plus I’ve been studying those images for days. Those bumps are mountain peaks on the huge South Pole-Aitken basin, obscured from our view, except for a few peaks on the south limb.

A slick white smear on the sunlit Cabeus crater wall bisected the elongated crater. You can see it on the – APOD lunar chart just above the red ellipse identifying Cabeus. It was really fun to watch the approach from the LCROSS camera on NASA TV, then scoot out the front door for views of the crater itself through our own telescope. I was looking at Cabeus at impact time and didn’t see (and didn’t expect to see) a plume. I recalled the night in 1999 when Mojo and I spent a night waiting and watching the South pole of the moon for the Lunar Prospector impact.

Some final thoughts a few days after LCROSS impact. The GAVRT radio telescope in the Mojave desert of California was abuzz with school kids around the world tracking LCROSS. The students locked onto the LCROSS signal and passed the information on to mission control. They will never forget this exciting mission and their important contribution to it! I was really impressed with the LCROSS mission E/PO and citizen science program which encouraged thousands of amateur astronomers like me to follow the mission, prepare an observing program and report observations.

Although sketches are not the same as video and images, I like thinking that I was sketching an area of the moon in the 400+ year old tradition of citizen scientists. The LCROSS mission follows in the tradition of trailblazing lunar missions. In fact, the mountain peak called M5 on Ewan Whitaker’s 1954 lunar map (on the limb south of Cabeus) is now named Mount Clementine!