Venus in the Daylight, on New years Eve

Following on from Tony Travaglia’s impressive image of Venus on New years Eve, here another one on New years Eve, but a little earlier.

An hour before Sunset, actually (you need to click on the image and get an enlarged version to see Venus clearly).

Now, as regular readers of this blog know, I’m obsessed with seeing Venus in the daytime.

While I’ve been quite good at catching Venus by eye, getting images has been much harder, and using my old Olympus Mu 300, the best images I could get were around 15 minutes before Sunset. This image is taken an hour before Sunset using my newish Canon IXUS 9015, ISO 100, 1/400 second shutter speed and F 18.6 with superfine resolution. There has been no post processing except for cropping and typing the Venus caption in.

I used the Moon to locate Venus, and a corner of the house and pergola to shut out the Sun and frame the Moon Venus combination.

As I’ve noted before, it always seems easier to locate Venus (or Jupiter) if there is a handy foreground object nearby. This is possibly due to the contrast making the eye “floaters” less obvious and making Venus more obvious. Using a wall/roof combination really helped to make Venus obvious, and also framed the image, making them easier to find while hunting in the full scale image.

Your next good opportunity to see Venus in the daylight is on January 30th, when the Moon is 45 degrees from the Sun, magnitude -4.5 and only 2 degrees (roughly two fingerwiths) above the 15% illuminated crescent Moon. Look for the thin crescent Moon, and Venus should be visible as a bright dot just above it. It’s best to look in the afternoon when the Sun is low and the sky is less bright. Make sure the Sun is hidden behind something solid like a building or a wall when you are looking for Venus, not trees or your hand. Exposing your eyes directly to the glare of the Sun can be very dangerous and you could potetially lose your sight.

If you can’t wait for 30th January, locate Venus around half an hour before Sunset, and find a conveniet marker (a tree, a teephone pole or something like that) close by to Venus from a fixed postion in your yard. Note the relative position of Venus and features on the marker. Next day, go to your viewing position about 5 minutes after Sunset and note Venus’s location. The next day, look 5 minutes before Sunset and note the location. And so on until you can see Venus well before Sunset. Do remember to be very careful not to look directly at the Sun when doing all of this. Chose your viewing location so that the Sun will be hidden well behind some solid object at all of your projected viewing times.

Good Luck Venus hunting!

The Moon and Venus on New Years Eve

This beautiful image of the Moon and Venus on New Years eve comes from Tony Travaglia of Otago, New Zealand. As usual, click on the image to see a larger version (with nice Earth shine). Lets hope 2009 will be a good year for all astrophotographers!

New Years Eve Lineup.

Evening sky as seen facing west in Adelaide at 9:00 pm ACST, December 31. Similar views will be seen elsewhere in Australia at similar local times.

2009 is almost upon us, but 2008 has one last beautiful astronomical view for us. The thin crescent Moon will be near Venus, with Mercury and Jupiter close by each other. This will be a very attractive start to the New Years Eve festivities.

So have fun everybody, stay safe, and if you are up late enough you can look at Saturn rising in the early morning sky. See you all in 2009.

Happy New Year 2009!

Happy New Year for 2009! Have a good one all of you! (Inmage is fireworks from the local jetty).

Carnival of Space #85 is here.

Carnival of Space #85 is now live at Cheap Astronomy. There is tales of the leap second, free astronomy lectures on line, Summer Solistice musings, Astronomy festivals, space exploration prizes, 200 year long space missions, space elevators and much, much more. Put on ypour New Years party hat and head on over.

New Years Eve Lineup.

Evening sky as seen facing west in Adelaide at 9:00 pm ACST, December 31. Similar views will be seen elsewhere in Australia at similar local times.

2009 is almost upon us, but 2008 has one last beautiful astronomical view for us. The thin crescent Moon will be near Venus, with Mercury and Jupiter close by each other. This will be a very attractive start to the New Years Eve festivities.

So have fun everybody, stay safe, and if you are up late enough you can look at Saturn rising in the early morning sky. See you all in 2009.

Well, at least I’m up there.

Hey, I got listed in the Top 100 Space and Astronomy Blogs. Okay, so I’m number 82, but I’m there. Actually the numbers don’t mean a heck of a lot as they sort of represent the top 10 in 10 different themes (Bad Astronomy comes in at number 44, but is really number 1 in “Space Professionals”). Lots of friends are there, Stuart’s, DaveP’s and Tom’s astronomy blogs are featured for example (as are most of the contributors to Carnival of Space). In fact, this list would be ideal as astronomy bookmarks, although I was surprised to see Top of the Lawn missing.

Hand Drawn Anaglyphs!

You may be familiar with red/(cyan or blue) anaglyphs. These are pictures where a 3D effect is produced by overlapping red and cyan (or blue) images. I have used anaglyphs to make stereo images of Mars and the Sun, for example.

A couple of days ago MiddleOne asked if you could draw 3D pictures. I thought it was possible from my experience with anaglyphs, and we experimented with various coloured textas, but with only minor successs.

Around 5:30 this morning SmallestOne kicked me out of bed, and I started thinking (or maybe I was already dreaming) about anaglyphs. I couldn’t go back to sleep, so I tried experimenting. First you need the right colour textas. Our stereo glasses have red for the left eye, and cyan for the right eye. You need a red colour that will be invisible through the left eye, and dark through the right eye, and a blue/green that is invisible through the right eye and dark in the left eye.

It was pretty easy to find a light red text that fitted the bill (our previous attempts had used too dark a red). Finding a blue-green that worked was much harder, and I had to settle for a pale green/blue that sort of worked.

Once you have your colours, then how do you match them up to give depth? I started with simple squares. Blue-green lines to the left of the red lines make the boxes appeare below the picture plane, blue-green to the right makes the boxes appear above the picture plane. The wider the lines apart, the greater the feeling of depth. by grading the line spacing, you can give a feeling of volume to the surface.

You also have to choose your viewing postion, straight up and down at about a meter away works best.

The planet with craters and rings above is the result. Viewing with red/cyan glasses about a meter away gives a nice 3D effect for the cratered body of the planet. The rings are a little wobbly though, but still, this was a hand drawn image using only red and blue-green textas. A little practise (and a better shade of blue-green), and you can draw stunning 3D images without fancy computer graphics programs.

The Universe is yours to discover during the International Year of Astronomy 2009

With 2009 just over the horizon, stargazers around the world are busy preparing for the International Year of Astronomy. A staggering 135 nations are collaborating to bring the Universe closer to Earth. Events and activities will take place over the coming 365 days and beyond, in a spectacle of cosmic proportions.

The International Year of Astronomy 2009 (IYA2009) has been launched by the International Astronomical Union (IAU) and the United Nations Educational, Scientific and Cultural Organization (UNESCO) under the theme, “The Universe, yours to discover”. Thousands of IYA2009 events are described on the national websites, as well as on astronomy2009.org, and a few of the global projects are listed here.

The official IYA2009 Opening Ceremony will take place in Paris on 15 and 16 January 2009, and the press is invited to attend. It will feature keynote speakers, including Nobel Laureates, and live video feeds to scientists working in remote locations. Many nations are holding their own Opening Ceremonies in January and February, showing their dedication to the Year. But events will begin before then. Don’t be surprised to see telescopes on the streets on New Year’s Day. The IYA2009 Solar Physics Group have been busy planning a grand worldwide campaign, with over 30 countries involved at more than 150 venues, which will see amateur stargazers set up their telescopes on pavements as well as in science centres, letting passers-by observe the Sun using special safety equipment.

The Cosmic Diary is an example of a global activity occurring during 2009, with the release of its official website on New Year’s Day. The project concerns the daily lives of full-time astronomers. More than 50 bloggers, professionals from over 35 countries and employed by organisations such as ESO, NASA, ESA and JAXA have already begun producing content, writing about their lives, the work they conduct and the challenges they face. The public can see what being an astronomer is really like, and how ground-breaking research is conducted. Another project, 365 Days of Astronomy, will publish one podcast per day over the entire year. The episodes will be written, recorded and produced by people around the world.

100 Hours of Astronomy, another IYA2009 Cornerstone Project, is a worldwide event taking place from 2-5 April 2009, with a wide range of public outreach activities including live webcasts, observing events and more. One of the key goals of 100 Hours of Astronomy is to have as many people as possible look through a telescope, just as Galileo did for the first time 400 years ago.

The From Earth to the Universe (FETTU) Cornerstone Project is an exhibition arranged by IYA2009 that will bring large-scale astronomical images to a wide public audience in non-traditional venues such as public parks and gardens, art museums, shopping malls and metro stations. Over 30 countries around the world are currently in the development phase of FETTU projects, many with multiple locations. Some 15 countries plan to begin FETTU exhibitions within the first month of 2009, ranging in size from 25 to over 100 images on display. FETTU will be introduced to the global community at the Opening Ceremony at UNESCO headquarters in January 2009.

The World at Night is an IYA2009 Special Project that is producing and bringing to the public a collection of stunning photographs and time-lapse videos of the world’s landmarks with the sky in the background. The World at Night is preparing more than 30 exhibitions and educational events around the world.

One of IYA2009’s aims is to raise awareness of light pollution, and how the beauty of the night sky is progressively being drowned out, particularly over urban areas. The project Dark Skies Awareness is tackling these issues head-on in a practical, inclusive manner. One way in which it is doing this is by holding star-counting events, where the public are encouraged to see how many stars in a particular area of the sky are actually visible from their location. When compared with data from truly dark sites, the results are often very surprising! The “How Many Stars” event will run from January 2009.

A list of event highlights is available on the official IYA2009 website, www.astronomy2009.org/highlights. From there it is also possible to contact the National Nodes, responsible for organising local events in the many participating countries.

During 2009, the sky will provide some exciting events, including the longest total solar eclipse of the 21st century, occurring on 22 July 2009 and lasting 6 minutes 39 seconds over a narrow corridor through countries including India, Bangladesh and China. A strong shower of Leonid meteors is also expected in mid-November 2009, with forecasters predicting upwards of an incredible 500 shooting stars per hour. In mid-October in the northern hemisphere, Jupiter will be placed at dusk, a perfect time to show public the giant planet and its moons. These are an impressive sight through even a small amateur telescope.

IYA2009 seeks to involve the public at large in its activities, and to this end amateur astronomers have been called upon to help organise and run events. Known for their enthusiasm, this army of helpers is growing every day, preparing to promote astronomy in a stunning variety of ways. In fact, so many thousands of people across the globe are already involved, they have formed the world’s largest ever astronomy network.

Catherine Cesarsky, IAU President, says: “135 countries have committed themselves to the Year, all pulling together toward the common aim of making astronomy accessible to the public. IYA2009 will reinforce the links between science education and science careers, stimulating a long-term increase in student enrolment in the fields of science and technology and an appreciation for lifelong learning.”

With such a range of activities planned, now is the ideal time to learn more about the cosmos and our place within it. The International Year of Astronomy 2009 promises to make the Universe yours to discover, beginning on 1 January 2009.

Notes for editors

IYA2009 marks the 400th anniversary of Galileo Galilei’s first astronomical observation through a telescope. It is nothing short of a worldwide celebration, promoting astronomy and its contribution to society and culture, with events at regional, national, and global levels.

The IAU is the international astronomical organisation that brings together almost 10 000 distinguished astronomers from all nations of the world. Its mission is to promote and safeguard the science of astronomy in all its aspects through international cooperation. The IAU also serves as the internationally recognised authority for assigning designations to celestial bodies and surface features on them. Founded in 1919, the IAU is the world’s largest professional body for astronomers.

IYA2009 welcome video: A special welcome video for IYA2009 is available. Hosted by Catherine Cesarsky, President of the International Astronomical Union, it is approximately five minutes in length and available in English, French and Spanish. The video is available for download from www.astronomy2009.org.

Additional information:

IYA2009 website: www.astronomy2009.org

IYA2009 Opening Events: www.astronomy2009.org/events

Opening Ceremony Media accreditation: www.astronomy2009.org/opening

UNESCO IYA2009 website: www.unesco.org/iya2009

Opening Ceremony website: http://www.astronomy2009.org/opening

Dawn of IYA2009 (Solar Physics Group) website: www.solarastronomy2009.org

Cosmic Diary website (active 1 January 2009): www.cosmicdiary.org

365 Days of Astronomy: http://365daysofastronomy.org

100 Hours of Astronomy: www.100hoursofastronomy.org

From Earth To The Universe: www.fromearthtotheuniverse.org

Dark Skies Awareness: www.darkskiesawareness.org

The World at Night: www.twanight.org

International Astronomical Union website: www.iau.org

IYA2009 welcome video: www.astronomy2009.org/resources/multimedia/videos/

For more information:

IAU IYA2009 Coordinator

Pedro Russo

ESO ePOD

Karl-Schwarzschild-Strasse 2

D-85748 Garching bei München

Germany

Tel: +49 89 320 06 195

Cell: +351 96285 4775 / +49 17661100211

Fax: +49 89 320 23 62

E-mail: prusso@eso.org

Further contacts

Yolanda Berenguer

UNESCO Focal Point for the International Year of Astronomy 2009

UNESCO HQ, Paris

Tel: +33-1-45684171

E-mail: y.berenguer@unesco.org

Dr. Karel A. van der Hucht

General Secretary, International Astronomical Union

IAU Secretariat, Paris, France

Tel: +33-1-43-25-83-58

E-mail: K.A.van.der.Hucht@sron.nl

IAU Press Officer

Lars Lindberg Christensen

ESO ePOD, Garching, Germany

Tel: +49 89 3200 6761

Cellular: +49-173-3872-621

E-mail: lars@eso.org

RCW 49

Credit: NASA/JPL-Caltech/E. Churchwell (University of Wisconsin)

New Image Shows the Power of Visual Remix The same way a visible-light photographer can choose to shoot black and white instead of color, astronomers using NASA’s Spitzer Space Telescope have their choice of what colors to use or not use in their images, as shown in an image of star-forming region RCW 49 released today.

The new picture is an alternate view of a dusty stellar nursery located 13,700 light-years away in the southern constellation Centaurus. Spitzer released its original version of the image in 2004. That image combined information from four different wavelengths of infrared light, but the new image uses only two.

The typical human eye perceives three different colors of visible light — red, green, and blue — with cones on the retina. All the colors we see are made up of some combination of these three colors. Every color of light has a different wavelength, and many wavelengths fall outside the visible spectrum. Infrared light is basically wavelengths of light that vibrate at colors below the red part of the spectrum, colors we can’t see.

Spitzer’s two imaging cameras effectively see a total of seven different wavelengths, or channels, of infrared light. That would be the equivalent of the eye being sensitive to seven colors instead of just three. The challenge for Spitzer imaging scientists is to present all these different channels using colors that we can see. When astronomers select which channels to include in their false-color composites, each wavelength is assigned a different visible-light color. Therefore, the same observations can be used to make very different images.

Spitzer’s two shortest wavelengths, 3.6 microns and 4.5 microns, were mapped as cyan and red respectively for the new image. At 4.5 microns, hot hydrogen gas glows very brightly, much like a neon light glowing in visible light. The two-channel image therefore emphasizes hot hydrogen gas, which shows up as the red regions, in addition to the more than 2,200 stars and organic molecules visible in both the two-channel and four-channel images.

As well as enabling exciting new science discoveries, two-channel images like this one are particularly interesting to scientists who wish to understand how Spitzer will perform after its liquid helium coolant runs out in 2009. At this time the telescope will become too warm to observe at longer wavelengths, but will continue to operate in these channels.

Object name: RCW 49 Object type: Star Formation Position (J2000): RA: 10h 24m 14.60s Dec: -57° 46′ 58.00″ Instrument: IRAC Wavelength: 3.6 Micron (Cyan), 4.5 Micron (Red)

Occultation of Jupiter, December 29, 2008

The western horizon as seen from Adelaide at 9:00 pm ACDST. Jupiter is behind the Moon.

Jupiter passes behind the Moon on Monday, December 29 2008. Occultations of bright planets, especially Jupiter, are both relatively rare (from any given spot on earth) and quite lovely.

With the Moon being a thin crescent, Mercury right next to it and Venus bright up above, this will be a spectacular occultation.

That’s the good news, the bad news is that the occultation occurs soon after Sunset. So for most sites (except Western Australia, where Jupiter goes behind the Moon before Sunset), Jupiter passes behind the Moon when the sky is still bright. This will be near impossible to see with the unaided eye, but will be easily visible in binoculars or a telescope. The exit of Jupiter from behind the bright crescent of the Moon occurs when the sky is reasonably dark (except in WA, where the sky is still quite bright), but when the Moon is quite low to the horizon, so you will need a fairly level, unobstructed horizon to see Jupiter emerge.

Still, while the conditions are quite difficult, the effort is well worth it. The occultation is best from South Eastern Australia, with most of Queensland and northern New South Wales missing out. A table with times for representative cities is here at Southern Skywatch. Strictly speaking, both Sydney and Darwin (shown as misses) see Jupiter go behind the Moon, but at only a few degrees above the horizon under twilight skies this will be very difficult to see. A fuller list of cities and times (in Universal Time), and a diagram of the occultation path is at the International Occultation Timing Site.

So good luck and clear skies for the occultation night!

Comet P/2008 X4 in SOHO

Remember comet P/2003 K2 (P/2008 X4) Christensen? Well it has crossed the field of view of the LASCO C3 camera of the SOHO spacecraft. At the time of writing it has gone behind the occulting disk, and has not yet reappeared.

The image to the left was taken on the 22nd at around 19h UT, the comet is indicated with a short line. You can download the latest video from SOHO here (but its 7 Mb and you need to look carefully at the last few frames) or you can download my AVI here (only 0.5 Mb).

Merry Christmas to All

Venus shines above the Christmas decorations down the street from us.

Merry Christmas, Happy Sun-return Festival, Happy New Year, and here’s hoping you are all safe from the loonies on the roads this festive season.

Tarantula Nebula - 30 Doradus

Credit: NASA/CXC/Penn State/L.Townsley, et al.

Drama In The Heart Of The Tarantula

Found in the nearby Large Magellanic Cloud, 30 Doradus is one of the largest massive star forming regions close to the Milky Way. Enormous stars in 30 Doradus, also known as the Tarantula Nebula, are producing intense radiation and searing winds of multimillion-degree gas that carve out gigantic bubbles in the surrounding cooler gas and dust. Other massive stars have raced through their evolution and exploded catastrophically as supernovae, expanding these bubbles into X-ray-brightened superbubbles. They leave behind pulsars as beacons of their former lives and expanding supernova remnants that trigger the collapse of giant clouds of dust and gas to form new generations of stars.

At the center of 30 Doradus lies the star cluster R136 at the intersection of three of these superbubbles. However, with ages only between one and two million years old, the stars in R136 are too young to be source of the supernovae that brighten the superbubbles in X-rays. Instead, R136 is most likely just the latest cluster to form in 30 Doradus. It may be as massive as it is because these superbubbles have combined to concentrate their gas in this region and thus triggered intense star formation there.

30 Doradus is about 160,000 light years from Earth in the southern constellation of Dorado. It spans 800 light years across and is incredibly bright in many wavelengths. If it were at the distance of the Orion Nebula (1,300 light years), 30 Doradus would span the area of 60 full Moons and its optical light would be bright enough to cast shadows at night on the Earth. This latest X-ray image of 30 Doradus represents almost 114,000 seconds, or 31 hours, of Chandra observing time - three times longer than previously recorded. In this image, red represents the lower range of X-rays that Chandra detects, the medium range is green, while the highest-energy X-rays are blue.

Fast Facts for Tarantula Nebula: Scale: Image is 24 arcmin across . Category: Normal Stars & Star Clusters Coordinates: (J2000) RA 05h 38m 42.9s | Dec -69° 06′ 3″ Constellation: Dorado Observation Dates: 09/21/1999 - 01/30/2006 Observation Time: 32 hours Obs. IDs: 22, 5906, 7263, 7264, 62520 Color Code: Red (0.5-0.7 keV); Green (0.7-1.1 keV); Blue (1.1-2.0 keV) Instrument: ACIS Distance Estimate: About 160,000 light years

Annotated Chandra Image of 30 Doradus

Fox Fur, a Unicorn, and a Christmas Tree

Credit & Copyright: R Jay Gabany

Clouds of glowing hydrogen gas fill this colorful skyscape in the faint but fanciful constellation Monoceros, the Unicorn. A star forming region cataloged as NGC 2264, the complex jumble of cosmic gas and dust is about 2,700 light-years distant and mixes reddish emission nebulae excited by energetic light from newborn stars with dark interstellar dust clouds.

Where the otherwise obscuring dust clouds lie close to the hot, young stars they also reflect starlight, forming blue reflection nebulae. The wide mosaic spans about 3/4 degree or nearly 1.5 full moons, covering 40 light-years at the distance of NGC 2264.

Its cast of cosmic characters includes the the Fox Fur Nebula, whose convoluted pelt lies at the upper left, bright variable star S Mon immersed in the blue-tinted haze just below the Fox Fur, and the Cone Nebula at the far right.

Of course, the stars of NGC 2264 are also known as the Christmas Tree star cluster. The triangular tree shape traced by the stars appears sideways here, with its apex at the Cone Nebula and its broader base centered near S Mon.

APOD

Mercury, Jupiter, Venus and a Merry Christmas

Christmas is coming! As well as the traditional roast animals, plum pudding and hot cocoa (which in Australia is a bit weird, as it’s hot and sunny here), you will get to see a nice line-up of Venus, Jupiter and Mercury.

The image to the left is the evening sky around 9:00 am local time in Australia on December 25. Jupiter and Mercury are close in the twilight, and Venus glows above. This will be a fine accompaniment to pre-dinner drinks or cracker pulling on Christmas evening.

As the days roll on, it gets better. Mercury and Jupiter come closer together, cumulating on the 29th with the occulatation of Jupiter, where the Moon passes in front of Jupiter, with Mercury nearby. This is Australia specific, New Zealand and most of South Asia will see Mercury, the Moon and Jupiter very close together, and South Africa will see them strung out in a line. Still very beautiful, and well worth watching though.

On the 31st the crescent Moon is very close to Venus, and Jupiter and Mercury are at their closest, a fine evening sight to herald in the New Year, and the International Year of Astronomy.

My posts will be a bit spotty now, with lots of relatives visiting, and food to cook and eat. So have a Merry and safe holdiay season, watch out for loonies on the road, and clear skies!

Carnival of Space #84 is now up.

Carnival of Space #84 is now up at the Next Big Future. There is news on the space exploration crisis, the suopercritical ocean on Venus, the top 10 best astrophotographs, lots more on Mars, engaging children in space Science and lots, lots more. So put on yur best space suit and head on over.

Impact Craters in Google Earth

While I’m on the subject of useful programs for amateur astronomy, Google earth has a number of useful features. You can get databases of impact structures (such as the Arcaman crater in South Australia pictures).

There are about 25 impact structures in Australia, ranging from the 90 Km Acraman structure to much smaller ones, here’s a partial list http://www.unb.ca/passc/ImpactDatabase/austr.html

See also http://www.abc.net.au/science/k2/trek/4wd/Over11.htm

A google earth KML for incorporating impact structures in google earth http://www.thinklemon.com/pages/ge Here is the Australian edition http://www.thinklemon.com/ge/impact-australia.kmz

There is also a more extensvie database maintained by the Impact Field Studies Group.

Astronomers Find Most Distant Water in the Universe

Credit: Milde Science Communication, STScI, CFHT, J.-C. Cuillandre, Coelum.

About this image: The spectrum — a radio “fingerprint” that revealed radio emission from water masers in the distant quasar MG J0414+0534. The background image is an infrared image of the quasar, made with the Hubble Space Telescope. The quasar appears broken up into four components by a foreground galaxy (diffuse object in the center), acting as a gravitational lens and strengthening the signal by a factor of 35. The inset with the galaxy M87 shows how the quasar might be seen from nearby.

Astronomers have found the most distant water yet seen in the Universe, in a galaxy more than 11 billion light-years from Earth. Previously, the most distant water had been seen in a galaxy less than 7 billion light-years from Earth.

Using the giant, 100-meter-diameter radio telescope in Effelsberg, Germany, and the National Science Foundation’s Very Large Array (VLA) in New Mexico, the scientists detected a telltale radio “fingerprint” of water molecules in the distant galaxy.

The soggy galaxy, dubbed MG J0414+0534, harbors a quasar — a supermassive black hole powering bright emission — at its core. In the region near the core, the water molecules are acting as masers, the radio equivalent of lasers, to amplify radio waves at a specific frequency.

The astronomers say their discovery indicates that such giant water masers were more common in the early Universe than they are today. MG J0414+0534 is seen as it was when the Universe was roughly one-sixth of its current age.

At the galaxy’s great distance, even the strengthening of the radio waves done by the masers would not by itself have made them strong enough to detect with the radio telescopes. However, the scientists got help from nature in the form of another galaxy, nearly 8 billion light-years away, located directly in the line of sight from MG J0414+0534 to Earth. That foreground galaxy’s gravity served as a lens to further brighten the more-distant galaxy and make the emission from the water molecules visible to the radio telescopes.

“We were only able to discover this distant water with the help of the gravitational lens,” said Violette Impellizzeri, an astronomer with the Max-Planck Institute for Radioastronomy (MPIfR) in Bonn, Germany. “This cosmic telescope reduced the amount of time needed to detect the water by a factor of about 1,000,” she added.

The astronomers first detected the water signal with the Effelsberg telescope. They then turned to the VLA’s sharper imaging capability to confirm that it was indeed coming from the distant galaxy. The gravitational lens produces not one, but four images of MG J0414+0534 as seen from Earth. Using the VLA, the scientists found the specific frequency attributable to the water masers in the two brightest of the four lensed images. The other two lensed images, they said, are too faint for detecting the water signal.

The radio frequency emitted by the water molecules was Doppler shifted by the expansion of the Universe from 22.2 GHz to 6.1 GHz.

Water masers have been found in numerous galaxies at closer distances. Typically, they are thought to arise in disks of molecules closely orbiting a supermassive black hole at the galaxy’s core. The amplified radio emission is more often observed when the orbiting disk is seen nearly edge-on. However, the astronomers said MG J0414+0534 is oriented with the disk almost face-on as seen from Earth.

“This may mean that the water molecules in the masers we’re seeing are not in the disk, but in the superfast jets of material being ejected by the gravitational power of the black hole,” explained John McKean, also of MPIfR.

Impellizzeri and McKean worked with Alan Roy, Christian Henkel, and Andreas Brunthaler, also of the Max-Planck Institute; Paola Castangia of the Max-Planck Institute and the INAF Astronomical Observatory of Cagliari in Italy; and Olaf Wucknitz of the Argelander Institute for Astronomy in Bonn, Germany. The scientists reported their results in the December 18 issue of the scientific journal Nature.

The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

Contact: Dave Finley, Public Information Officer Socorro, NM (575) 835-7302 dfinley@nrao.edu

Making SCC files for Celestia

In a previous post I gave links to Celestia SSC files you could download in order to see C/2003 K2 Christensen from the point of view of the STEREO space craft (and Earth). But what happens if a new comet appears and you want to see where that is? Well, you could wait for me to make one and post it, or you could make your own. How can you make your own SSC files?

SSC files are fairly simple text files. Here’s the content of the 164P-Christensen.ssc file

# 164P C/2008 X4 C/2003 K2 Christensen “164P-Christensen” “Sol” { Class “comet” Mesh “roughsphere.cms” Texture “asteroid.jpg”

EllipticalOrbit # elements for epoch 2008 11 30 { Epoch 2454820.4610 # 2008-Nov-30.0000000 Period 5.66 PericenterDistance 0.5348106 Eccentricity 0.8316730 Inclination 10.21560 AscendingNode 93.89279 ArgOfPericenter 345.76428 MeanAnomaly 0.0 }

InfoURL “http://astroblogger.blogspot.com/2008/12/comet-al-recovers-comet-p2003-k2.html” Radius 10.45 # Hn=12.50 Hn=14.10-2.5*log(Albedo)-5*log(Radius) Albedo=0.04 Orientation [ 90 0 0 1 ] # random value RotationPeriod 15.613880 # random value Obliquity 77.387310 # random value EquatorAscendingNode 239.190649 # random value Albedo 0.04 }

First off you can ignore everything under InfoURL, they are made up figures as newly discovered comets will not have this data. All you really need is the orbital elements, so where do you get these? From the Minor Planet Center, where else?

Now, you can get them in three ways, if the comet is really recent, you can look up the Minor Planet Electronic Circular. Otherwise, you can use either the Orbital elements of comets page, or you can use the Minor Planet Comet and Ephemeris Service. As a demonstration, I’ll use the Ephemeris service. After clicking on the ephemeris service link, scroll down and type your comet in the box (use P/2008 X4 for this demonstration), then scroll down the Ephemeris Options below, ignoring all except the “Also display elements for epoch” box. Type the current date in there using year-month-day format 2008-12-18. Ignore everything else and click on the Get Ephemeris button.

Down the bottom of the resulting page you will see:

Epoch (TT/JD) T (TT/JD)         Peri.     Node      Incl.       e             q             a      Epoch (TT)2454818.50000 2454820.4610294 345.76463  93.89262  10.21562 0.8316725     0.5348100      3.17720  2008/12/18.00

Which look almost nothing like Epoch 2454820.4610 # 2008-Nov-30.0000000 Period 5.66 PericenterDistance 0.5348106 Eccentricity 0.8316730 Inclination 10.21560 AscendingNode 93.89279 ArgOfPericenter 345.76428 MeanAnomaly 0.0

So Epoch = Epoch, that’s clear. Except for P/2008 X4 I had to use the second of the two Epoch dates to get the comet in the right place. Peri = ArgOfPericentre, Node = Ascending node, Incl = Inclination(so far so good), e? what the heck is e? e= eccentricity (hey obvious), q = PericenterDistance (only Celestia uses Pericenter, everyone else uses Perihelion), ignore a and use 0.0 for mean anomaly.

Where is the Period you ask. Good question, it’s not there. But see the link up the top? Perturbed ephemeris below is based on elements from MPEC 2008-X81. Click on that, scroll down and just before the residual you will find P 5.66.This won’t work for all comets, the old, established comets don’t have that link but new ones will (obviously the name of the link will be different for other comets).

Alternatively you can use the JPL Horizons system. There PER is period (but that currently gives the WRONG orbital elements for P/2008 X4, it uses the old P/2003 K2 elements, which is why I didn’t go there in the first place), or if you are lucky it will be listed in Wikipedia (here is a list of all currently known period comets, but without C/2008 X4).

For known comets that aren’t currently incuded in the Celestia main download, go to the Celestia Motherload comets page. There is a full catalog of periodic comets there (minus P/2008 X4 of course), but if you download that into extras and turn the orbts on, you won’t see a thing for comet orbits. It may be best if you store this file somehwere ellse and extract comets as you need them.

Happy SSC file making (you can now do this for new asteroids and exoplanets as well)