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Movie of Saturn Moon Passing through Gap in Ring Shadows

Tue, 19 Jan 2010 20:30:00 PST

Details on this Video of Saturn's Moon Janus

Now this took some careful planning. The pictures were taken before-during-and after the sunlight coming through the Cassini division in Saturn's rings passed over the moon Janus. It's neat to think about what is going on, and that we have footage from a mere quarter of a million kilometers (2.5 x 10⁵) away (in contrast, we on Earth were about 1.55 x 10⁹ km away at that time). This occurred on August 27, 2009.

Cassinis 7th Enceladus Flyby Images

Tue, 3 Nov 2009 20:01:36 PST

The NASA Saturn orbiting spacecraft Cassini flew by Saturn's arguably most interesting moon Enceladus for the 7th time on November 2, 2009. It targeted its flyby at a mere 99km (62 mi) at its closest approach, straight through the watery plumes. The raw images are available on the Cassini website, and the unique vantage point of the orbiter's cameras is simply stunning. You can search through the photos yourself by choosing "ENCELADUS" as the Target and choosing "Newest" for the Observation Time. Here are a couple of examples of images of the moon's plumes:

Incredible!

The white specks are noise in the camera image which are usually filtered out in processed images. These are raw images, so of course no ground processing done yet to them. These were taken from hundreds of thousands of kilometers away.

More images nearer to the closest approach are here:

This was taken from about 10,000km away. I love how Saturn's rings show up in the background.

This was taken a few thousand km further away, but zoomed in on the surface. Intricate detail!

Jupiter and Moon Astrophotography Shoot

Tue, 27 Oct 2009 12:21:36 PDT

I had the Meade 70mm refractor telescope for awhile, and I also have a Nikon D40 digital SLR camera, so I only needed to connect the two in order to get some astrophotography shots*. I finally received the two pieces necessary to connect the camera to the telescope as a birthday gift (thanks Mom & Dad!), and some of the first fruits are pics of Jupiter and Luna.

Jupiter

Right now is close to the best time of year to see and image Jupiter (along with its four Galilean moons). I had my camera/scope pointed at Jupiter and was adjusting the exposure time to get pictures with the moons visible and planet overexposed and also moons not visible and planet features showing well. A man walked up (turned out to be a fellow amateur astronomer) and asked about the setup, and suggested that I take a series of pictures and use computer software to process and stack them, bringing out the cloud band features. I only took 10 pictures, but was quite pleased with the result:

The top picture above is a single unprocessed exposure (except it's cropped), and the next is the final stacked image. It looks less round and more flat in the stacked image, so I can use some practice with the software, but the features are greatly improved. The software is Registax 5 by the way.

In the uncropped image, the planet hardly takes up any of the rectangular image frame (i.e. it is mostly black):

So it is clear that for planetary imaging my setup will need some magnification. A lot of wasted pixels there! I posted a question to the Cloudy Nights forum, and was informed of two methods of astrophotography magnification: barlow lenses and eyepiece projection. I'll explain those another time. Both would require additional equipment to append to my current setup.

Luna

Almost anytime is a good time to photograph the moon, so I did that as well over the weekend. The image of the half-moon looked so crisp at the time that I didn't bother taking a multitude for stacking purposes, but after getting the results with the Jupiter photo, I took the 4 or 5 images of the moon that I had and ran them through Registax also. It certainly makes for a very professional looking moon photo (original on top, processed/stacked on bottom):

I should mention that in the processed moon image, it was also converted to black and white. I'll see what difference is made with even more images to stack.

For the future, I can either invest in the above (and below) mentioned equipment to magnify the view for planetary astrophotography, or purchase a tracking motor for the equatorial mount so I can take beautiful wide-field photos.

* Connecting them requires a 1.25" eyepiece socket to standard T-mount adapter, and a T-mount to Nikon specific camera adapter. A barlow lens would fit between the scope and the first adapter. An eyepiece projection adapter is the same as the 1.25" to T-mount adapter except an eyepiece can be placed inside.

Images of LCROSS Impact

Some preliminary results showing the flash and thermal signature of the LCROSS Centaur impact have been posted online. First, for background information, the previous posts I wrote on this mission are located at: 1st LCROSS post, Viewing locations, and Post-impact first impressions.

Astronomy Picture of the Day posted an image taken in Mid-Infrared of the Centaur impact flash as seen from the LCROSS spacecraft, confirmation for any doubters who watched it live online. Post-processing can bring out details that cannot be revealed in realtime.

Secondly, the LRO spacecraft that was launched along with LCROSS made pre and post impact passes over the impact site, and the thermal data is online for comparison here at the NASA LCROSS official site. It shows an obvious dot of increased temperature in the middle of the large cold area in permanent shadow of the crater.

The main reason for the Lunar CRater Observation and Sensing Satellite was to cause the moon dust to fly up in an area thought potentially likely to contain water. That was accomplished, and the data acquired from this plume of material, and this data is still being carefully analyzed for traces of water. Those results are still to come.

LCROSS Lunar Impacts Viewing a Disappointment

If you got up earlier than usual to watch the LCROSS spacecraft impacts live online, or even with a 10+ inch telescope, you might be regretting the sacrifice of sleep because the impact did not produce the expected "bang". I didn't have any regrets, because it was neat watching the footage of the final moments before impact from the front row vantage point of the LCROSS spacecraft itself. Knowing that it was happening at that very moment is just fascinating.

So what now?

Fortunately, it's not over yet. What we saw was only the successive images from one of the cameras (and a little bit from the infrared sensor). There is still much more data that was captured before the spacecraft's ending and downlinked to Earth, which is yet to be processed, evaluated, and disseminated. Also, many professional astronomers were utilizing the most technologically advanced ground-based telescopes to image the impact. Finally, the Hubble telescope and LRO spacecraft were also pointed at the Cabeus crater. All of these images have yet to be processed and distributed as well, and I cannot wait!

If you want to be notified by email as soon as more results are released, click here and enter your email in the form at the bottom of the page
(Of course, we all hate spam so all you will be sent is only what you want)

Palomar 200 inch telescope image of crater 11 seconds post impact

Watch LCROSS Moon Impact Live

As you probably know, the NASA Lunar CRater Observation and Sensing Satellite's (LCROSS) Centaur upper stage is on a collision course for a crater near the South-pole of the moon called Cabeus after midnight tonight (which will be the early morning of Oct 9, 2009). The Centaur upper stage rocket carried both the LRO and LCROSS spacecrafts to Lunar orbit, and will remain attached to LCROSS until released for the impact trajectory. About 4 minutes after the empty upper stage strikes, the LCROSS spacecraft itself will pass through the resulting ejected plume, sending data back to Earth while sensing the particles and snapping pictures, and also impact the crater.

The exact time of the first impact (as of this writing) is Oct 9, 2009 at 4:31:19 PST. Read my earlier post for more details.

Want a cool place to watch the impact?

The point of this update is to announce:

Viewing at NASA-JPL at the Von Karman Auditorium is open to the public and the gates will open at 3:00 am PST (Oct 9, 2009). So if you live in Southern California, set your alarm early enough to allow you time to:

Get some coffee
Get to JPL (4800 Oak Grove Dr., Pasadena, CA 91109)
Park
And find your way to the Auditorium (there are signs pointing you there)

If you do not live in the L.A. area, there are other viewing parties around the USA, or watch it live online at NASA TV.

This is NOT how the moon will look tonight, because I took this picture back in April of this year. To see a moon phase calendar for October 2009 click here.

Chinese Moon Festival 2009

The Chinese Moon Festival this year occurs on October 3rd. How is the date of the Mid-autumn festival determined?

The holiday marks the 15th day in the 8th month of the lunar calendar year, i.e. the 8th full-moon of the year. So on 10/3/2009 the moon will be its fullest and brightest. Also notable in the sky along with the full moon will be the planet Jupiter shining brightly as well. Jupiter is very easy to spot as the 2nd brightest object in the night sky. This is because Earth recently passed Opposition with Jupiter, which is the point at which Earth is closest to Jupiter during Earth's yearly orbit.

Uranus is between the moon and Jupiter this night, but a better time to track it down would be when the moon is not full and brightening up the whole sky.

In Chinese culture, a dessert called "Moon cakes" are eaten during the Moon Festival. Usually they are about 1.5 inches thick and square, about 3 inches on each side. See the images below of one (tasty) example:

What is especially unique about this year's Moon Festival is that less than 6 days afterwards, the LCROSS launch vehicle upper-stage will crash into the Lunar South Pole. You can watch it live online as seen from the LCROSS spacecraft.

LCROSS Impact on the Moon Visible from Western Hemisphere

Shortly after the launch of the NASA LRO/LCROSS spacecrafts from Florida on June 18, 2009, I checked to see if the moon would be in North America's part of the sky at the time of the estimated impact of LCROSS into the surface of the moon. The result: NO :-( *sniff sniff*. The moon would be over Asia, and seeing the moon from the USA would require looking directly through the Earth.

Flash forward to today and well you already know the good news from the title, the LCROSS impact of the Lunar south pole will be visible from the entire Western Hemisphere!. I verified this by checking the LCROSS official website, which has a projection for the impact time in October listed. Then I opened Home Planet 3, put in my location of Redondo Beach, CA, and the impact time, and the sky view shows the moon almost directly at the zenith (right overhead)! Therefore, I either made a mistake when I checked the moon's location the first time, or there was a change to the ETA of the impact.

Encoded on this blog post is an applet that automatically checks the official LCROSS website and displays just the projected impact time here, so this post (though not this email) will always be up-to-date even though it is written over 3 weeks before impact:

Projected Impact at time of this writing: Oct 9, 11:30 UT (7:30 EDT, 4:30 PDT)

Also, the following image shows Earth and the Moon projected onto the Earth at the time of impact.

Location of Moon over Earth at time of LCROSS impact on Lunar South Pole

The phase of the moon shown is correct, waning gibbous. Also, here is the view of the sky from Southern California that night:

I have heard that the impact will be in the shadowed part of the moon (i.e. not the illuminated side, but also not the "dark side" of the moon that humans on Earth never see either), close to the terminator (line between light and dark). So when the dust flies up from the impact, it will be illuminated by the Sun.
I've also heard that it will only be visible with at least 10 inch telescopes, but I will still try myself anyways, with my humble 3 inch refractor.

Good luck watching! (Here's an official link to observability: lcross.arc.nasa.gov/observation/amateur.htm) Also I checked to see if any locations outside of North/South America will have a view of the moon during impact, and the result is that the moon will be near the horizon for Western Europe and Africa, and the East coast of Asia (including Korea, Japan, and East Russia). South America will be entirely bathed in the sunlight of morning, and the hour in Europe will be the afternoon, making viewing with smaller aperture telescopes even less likely there.

Winning Hubble Telescope Contest Target

Towards the end of January I wrote a post about the contest that NASA held online to vote from a panel of six candidates for a target to point the Hubble Space Telescope (HST) at. As you probably already heard, a great choice was made by the voters: Arp 274, a group of three interesting galaxies. It received about 47.9% of the vote, out of about 140,000 votes.

Arp 274 HST Image

The above image is the result of the contest. The galaxy group was imaged from April 1-2, 2009. It reveals that the three galaxies are in fact not gravitationally perturbing one another, as previously thought. That is because the galaxies are all keeping their shapes intact, and therefore are not actually near one another but only coincide in our line of sight.

A high-resolution image can be downloaded here, where you can see in detail for yourself the beautiful barred spirals and smaller compact galaxy. Of course, the voting contest for the naming of the new International Space Station module garnered much more attention, but the only thing that came out of that was an exercise bike dubbed COLBERT.

Orion Astrophotography Webinar

I receive emails from Orion® Telescopes & Binoculars every so often (ever since I made a purchase online), sometimes with informative articles and sometimes with advertisements for astronomy goodies.

The last email I received today not only advertised a free shipping sale applicable over the weekend, but also an Astrophotography "Webinar". Since I am quite interested in getting into astrophotography myself, I am telling whoever reads this about their webinar.

It is actually an encore of a past webinar, back by popular demand, entitled "Introduction to Astro-Imaging". It will occur online on Thursday June 4, 2009, from 5pm to 6pm Pacific time. Here is the link to register. The email states that virtual space/seats are limited. First come, first served.

If you are lucky, see Shuttle Mission STS-125

As you are aware, Space Shuttle mission STS-125 is currently orbiting high above the Earth, with the famed Hubble Space Telescope (HST) captured and mounted perpendicularly in the bay. I was curious if there would be any opportunities to see the combination of HST and Space Shuttle streaking by in the night sky for us in North America, so I consulted a great online tool to determine suitable overhead tracks (if you are not in North America, then try it for yourself and perhaps you will have better luck).

Heavens Above is a very informative site that any amateur astronomer should have in his or her toolbag (i.e. bookmarked in your browser). It can display Earth orbiting satellite overhead tracks, customized for any latitude and longitude. The site also keeps track of the brightest comets currently visible, as well as other interesting tidbits.

What it shows for Los Angeles is that STS-125 will pass overhead early in the morning on May 22, from 05:26 to 05:28 PST, albeit at a mere 10 to 12 degrees in altitude. It will appear towards the south, and orbit towards the southeast.

STS-125 is scheduled to land at 11:41 am EDT, so California is fortunate to have this one opportunity to see the bright reflecting shuttle streaking by, although the telescope will already be separated from the shuttle by that time.

Unfortunately, the shuttle overhead pass is below the horizon for people residing much further east of California. Floridians will be able to hear the sonic-boom as the shuttle descends through the atmosphere however!

Double Moon Shadow Transit across Jupiter

Tonight Jupiter's Galileon moons Callisto and Io will transit the disk of Jupiter. It is very difficult to see the moons themselves when they are in front of Jupiter, but what is special is that their shadows will also fall on the planet Jupiter simultaneously for a few hours. It is much easier to see the shadows track across the planet, and I have seen a single moon transit once with my humble 70mm refractor.

The Sky and Telescope Jupiter moons utility tells exactly when each moon shadow transit starts and ends:

Moon Event	Time (UTC)
Callisto's shadow begins to cross Jupiter	5/17/2009 04:38
Io's shadow begins to cross Jupiter	5/17/2009 07:52
Callisto's shadow leaves Jupiter's disk	5/17/2009 09:36
Io's shadow leaves Jupiter's disk	5/17/2009 10:14

Cassini Website Wins Webby Science Award

I am a few days behind the curve reporting this, but it is an honorable mention. The Cassini-Huygens mission to Saturn and its largest moon Titan has returned an unfathomable amount of extraordinary science data and breathtaking images. If you have not yet visited the mission website, it presents the latest processed images in a very cool way, and makes it easy to search for archived images, articles, and other information. You can even view raw images, and attempt to spot interesting details before the Cassini scientists themselves do.

With that background, it is not a terribly big surprise that a U.S. government or NASA website took first prize for the 2009 Science Webby award. Speaking of which, NASA.gov also clenched the title for best government website again this year.

Cassini JPL Website

See Venus during the Daytime

Just in case you're one of those people who need to sleep at night, there is still hope to see cool things in the sky. You have seen the moon during the day with the naked eye, but you can also see Venus through binoculars or a telescope during the day. CAUTION: Never point a magnifying device at the Sun, such as a telescope or binoculars, as it will cause you to become permanently blind.

That being said, a few weeks ago my wife and I went to the beach on a clear sunny day equipped with beach towels, a parasol, and binoculars. Currently Venus is to the west of the Sun in the sky, so as I was lying under the parasol being certain that it was blocking the sunlight, I scanned west of the Sun with binoculars until I spotted the crescent Venus. It looked AWESOME! The shape was like a boomerang.

You have to see it for yourself.

A bit childish, but a picture is worth a thousand words

According to Horizons, Venus is currently about 35% illuminated and waxing, and will be 50% illuminated from our point of view on June 7, 2009.

As you probably know, you can view the Sun itself if you use an appropriate sun filter on your telescope, which I do not have but am interested in of course. That discussion, however, is for another post.

NASA Mission Madness Contest

NASA's TV program NASA Edge is holding a contest to democratically elect the public's favorite "space" mission. I put "space" in quotations because it is arguable that some of the competitors did not technically go into "outer space" as the accepted definition of "space" holds, which is 100 km above sea level (SR-71 is one such example, whose justification is that the pilots needed to wear pressurized spacesuits to go to their operating altitude).

The final winner will be narrowed down in 6 stages, from two starting groups of 32 competitors each. NASA attempted to make the contest as similar to the NCAA (National Collegiate Athletic Association, for once that is not a space related FLA (Four-Letter Acronym)) basketball March Madness setup as possible, see for yourself here: NASA Mission Madness bracket.

Actually, the official Mission Madness bracket looks more basketball related than the NCAA contest's bracket that it tries to be like, see the following comparison:

NASA Edge Mission Madness tournament bracket

Note the basketball and hoop

NCAA Basketball March Madness tournament bracket

No such basketball paraphernalia pictured in the original March Madness bracket, except for some faded out X's and O's on a court play strategy in the background.

I have digressed. The contest began yesterday March 19, 2009 and ends on April 8, 2009. As an email to NASA personnel explained, the public can also "learn about mission goals..." "and predict which missions their fellow fans will vote for during the single elimination round." The contest also has no limit to the number of votes allowed per person, so if you really want a particular mission to win, you could skip sleeping and vote for it 24/7. The place to go to vote (again and again) is: http://mission-madness.nasa.gov

As hinted at above, there is quite a range of missions to vote for, from the early Gemini IV mission to the LRO/LCROSS spacecraft which has yet to launch this year, and from an altitude that the NASA modified B52 called NB-52 flies at to outside of our solar system with Voyagers 1 and 2. On the site you can pull up quick info on each mission before you vote.