Tuesday, September 29, 2009
The Sky This Week - Thursday October 1 to Thursday October 8
The Full Moon is Sunday October 3. Jupiter is is easily seen as the brightest object in the evening sky. In the morning, Venus and Mars are seen above the eastern horizon before dawn. Venus and the bright star Regulus are close on Monday September 21. Mercury is lost in the evening twilight.
Evening sky looking east at 7:30 pm local time on Wednesday October 1. Click to embiggen.
The Full Moon is Sunday October 3.
Mercury is low in the morning twilight glow. On Thursday October 8 Mercury and Saturn are close together just above the horizon (see below).
Saturn reappears low in the morning sky this week.
Jupiter is easily seen as the brightest object in the evening sky. Jupiter is big enough to be appreciated in even the smallest telescope. If you don't have a telescope to view Jupiter, why not go to one of your local Astronomical Societies or Planetariums open nights? Jupiter's Moons are readily visible in binoculars or a small telescope.
Eastern horizon with Venus, Mercury and Saturn at 5:30 am local time on Thursday morning October 8, click to embiggen.
In the morning, Venus and Mars are visible in the eastern sky. Red Mars is in the constellation of Gemini.
Bright white Venus is close to the horizon, but is still readily visible in the dawn twilight if you have a clear, unobstructed horizon. Thursday morning October 8 Venus is close to Mercury and Saturn. This is will require a clear,level horizon to see, and probably binoculars to see faint Mercury and Saturn in the twilight. During the week Venus comes even closer to the horizon.
Printable PDF maps of the Eastern sky at 10 pm, Western sky at 10 pm. For further details and more information on what's up in the sky, see Southern Skywatch. Cloud cover predictions can be found at SkippySky.
Evening sky looking east at 7:30 pm local time on Wednesday October 1. Click to embiggen.The Full Moon is Sunday October 3.
Mercury is low in the morning twilight glow. On Thursday October 8 Mercury and Saturn are close together just above the horizon (see below).
Saturn reappears low in the morning sky this week.
Jupiter is easily seen as the brightest object in the evening sky. Jupiter is big enough to be appreciated in even the smallest telescope. If you don't have a telescope to view Jupiter, why not go to one of your local Astronomical Societies or Planetariums open nights? Jupiter's Moons are readily visible in binoculars or a small telescope.
Eastern horizon with Venus, Mercury and Saturn at 5:30 am local time on Thursday morning October 8, click to embiggen.In the morning, Venus and Mars are visible in the eastern sky. Red Mars is in the constellation of Gemini.
Bright white Venus is close to the horizon, but is still readily visible in the dawn twilight if you have a clear, unobstructed horizon. Thursday morning October 8 Venus is close to Mercury and Saturn. This is will require a clear,level horizon to see, and probably binoculars to see faint Mercury and Saturn in the twilight. During the week Venus comes even closer to the horizon.
Printable PDF maps of the Eastern sky at 10 pm, Western sky at 10 pm. For further details and more information on what's up in the sky, see Southern Skywatch. Cloud cover predictions can be found at SkippySky.
Labels: weekly sky
Tuesday, September 22, 2009
The Sky This Week - Thursday September 24 to Thursday October 1
The First Quarter Moon is Saturday September 26. Jupiter is is easily seen as the brightest object in the evening sky and is visited by the Moon on Tuesday September 29. In the morning, Venus and Mars are seen above the eastern horizon before dawn. Mercury appears low in the morning twilight later in the week.
Evening sky looking east at 7:30 pm local time on Tuesday September 29. Click to embiggen.
The First Quarter Moon is Saturday September 26.
Mercury appears low in the morning twilight glow later in the week. It will be very difficult to see without a clear level horizon.
Saturn is no longer visible, and will reappear in the morning in October.
Jupiter is easily seen as the brightest object in the evening sky. Jupiter is visited by the Moon on Tuesday September 29. This is an excellent time to see Jupiter during the daytime. Look for the Moon above the horizon an hour before sunset, and you should see Jupiter just below it.
Jupiter is big enough to be appreciated in even the smallest telescope. If you don't have a telescope to view Jupiter, why not go to one of your local Astronomical Societies or Planetariums open nights? Jupiter's Moons are readily visible in binoculars or a small telescope. On Thursday September 24 Jupiter has an interesting alignment of Moons.
Eastern horizon with Venus and Mercury at 5:30 am local time on Monday morning September 28, click to embiggen.
In the morning, Venus and Mars are readily visible in the eastern sky. Red Mars is in the constellation of Gemini.
Bright white Venus is close to the horizon, but is still readily visible in the dawn twilight if you have a clear, unobstructed horizon. During the week Venus comes closer to the horizon.
Printable PDF maps of the Eastern sky at 10 pm, Western sky at 10 pm. For further details and more information on what's up in the sky, see Southern Skywatch. Cloud cover predictions can be found at SkippySky.
Evening sky looking east at 7:30 pm local time on Tuesday September 29. Click to embiggen.The First Quarter Moon is Saturday September 26.
Mercury appears low in the morning twilight glow later in the week. It will be very difficult to see without a clear level horizon.
Saturn is no longer visible, and will reappear in the morning in October.
Jupiter is easily seen as the brightest object in the evening sky. Jupiter is visited by the Moon on Tuesday September 29. This is an excellent time to see Jupiter during the daytime. Look for the Moon above the horizon an hour before sunset, and you should see Jupiter just below it.
Jupiter is big enough to be appreciated in even the smallest telescope. If you don't have a telescope to view Jupiter, why not go to one of your local Astronomical Societies or Planetariums open nights? Jupiter's Moons are readily visible in binoculars or a small telescope. On Thursday September 24 Jupiter has an interesting alignment of Moons.
Eastern horizon with Venus and Mercury at 5:30 am local time on Monday morning September 28, click to embiggen.In the morning, Venus and Mars are readily visible in the eastern sky. Red Mars is in the constellation of Gemini.
Bright white Venus is close to the horizon, but is still readily visible in the dawn twilight if you have a clear, unobstructed horizon. During the week Venus comes closer to the horizon.
Printable PDF maps of the Eastern sky at 10 pm, Western sky at 10 pm. For further details and more information on what's up in the sky, see Southern Skywatch. Cloud cover predictions can be found at SkippySky.
Labels: weekly sky
Friday, September 18, 2009
Where were those Asteroids Hiding
If you were wondering about the asteroids I mentioned in yesterdays post about my complete inability to find L4 asteroids, here they are (clcik image to embiggen). The square shows the approximate field of view of the STEREO H1 instrument (and hence the extent of the image in yesterdays post).There is 8 Flora, 14 Irene, 146 Lucinda, 103 Hecate, 54 Alexandra, 451 Patientia, 409 Aspasia and 25 Phocaea. Comet 88P is also shown, but was cropped out in my overlay image.
One good thing about all this work is that if a new Asteriod does turn up, I know the locations of the known ones. So this makes the work of finding L4 asteroids a bit easier now.
In the next few days 187 Lambeta and 70 Panopea will enter from the lefthand side.
Labels: asteroids, Stereo Satellite
Thursday, September 17, 2009
STEREO at L4
Hidden in this picture are 8 cute little asteroids. Can you find them?Unfortunately, none of them are unknown L4 asteroids. the STEREO spacecraft is passing through the L4 Lagrange point at the moment, and hopefully a Trojan asteroid will wander through its field of view. But not yet it seems.
Labels: asteroids, Stereo Satellite
Wednesday, September 16, 2009
The Moon, Venus and Regulus
Eastern horizon with Venus and the Moon at 5:30 am local time on Thursday morning September 17, click to embiggen.Just a reminder that tomorrow morning (Thursday September 17) Venus is near the crescent Moon and the bright star Regulus, foring an attractive triangle.
This will be difficult to observe if you do not have a level clear eastern/north eastern horizon as the grouping is close to the horizon.
Labels: Moon, unaided eye observation, Venus
Tuesday, September 15, 2009
The Sky This Week - Thursday September 17 to Thursday September 24
The New Moon is Saturday September 19. Mercury is lost in the evening twilight. Jupiter is is easily seen as the brightest object in the evening sky. In the morning, Venus and Mars are seen above the eastern horizon before dawn. Venus and the bright star Regulus are close on Monday September 21.
Evening sky looking east at 7:30 pm local time on Monday September 21. Click to embiggen.
The New Moon is Saturday September 19.
Mercury is lost in the twilight glow.
Earth is at equinox on Wednesday September 23. Day and night are of equal length and the Sun rises due east.
Saturn is no longer visible, and will reappear in the morning in October.
Jupiter is easily seen as the brightest object in the evening sky. While Jupiter is past opposition, where it is biggest and brightest as seen from Earth, it is still more than big enough to be appreciated in even the smallest telescope. If you don't have a telescope to view Jupiter, why not go to one of your local Astronomical Societies or Planetariums open nights? Jupiter's Moons are readily visible in binoculars or a small telescope. On Friday September 18 and Thursday September 24 Jupiter has an interesting alignment of Moons.
Eastern horizon with Venus and Regulus at 5:30 am local time on Monday morning September 21, click to embiggen.
In the morning, Venus and Mars are readily visible in the eastern sky. Red Mars is in the constellation of Gemini.
Bright white Venus is close to the horizon, but is still readily visible in the dawn twilight if you have a clear, unobstructed horizon. On Monday September 21 Venus is near the bright white star Regulus. During the week Venus comes closer to the horizon.
Printable PDF maps of the Eastern sky at 10 pm, Western sky at 10 pm. For further details and more information on what's up in the sky, see Southern Skywatch. Cloud cover predictions can be found at SkippySky.
Evening sky looking east at 7:30 pm local time on Monday September 21. Click to embiggen.The New Moon is Saturday September 19.
Mercury is lost in the twilight glow.
Earth is at equinox on Wednesday September 23. Day and night are of equal length and the Sun rises due east.
Saturn is no longer visible, and will reappear in the morning in October.
Jupiter is easily seen as the brightest object in the evening sky. While Jupiter is past opposition, where it is biggest and brightest as seen from Earth, it is still more than big enough to be appreciated in even the smallest telescope. If you don't have a telescope to view Jupiter, why not go to one of your local Astronomical Societies or Planetariums open nights? Jupiter's Moons are readily visible in binoculars or a small telescope. On Friday September 18 and Thursday September 24 Jupiter has an interesting alignment of Moons.
Eastern horizon with Venus and Regulus at 5:30 am local time on Monday morning September 21, click to embiggen.In the morning, Venus and Mars are readily visible in the eastern sky. Red Mars is in the constellation of Gemini.
Bright white Venus is close to the horizon, but is still readily visible in the dawn twilight if you have a clear, unobstructed horizon. On Monday September 21 Venus is near the bright white star Regulus. During the week Venus comes closer to the horizon.
Printable PDF maps of the Eastern sky at 10 pm, Western sky at 10 pm. For further details and more information on what's up in the sky, see Southern Skywatch. Cloud cover predictions can be found at SkippySky.
Labels: weekly sky
Monday, September 14, 2009
Carnival of Space #120 is here.
Carnival of Space #120 is now up at Music of the Spheres. Hubbles new images is the headline act, then there's a tour of the planets, why is the Moonset so red, how space based technologies can improve our lives, astronomical coincidences, the Universe Sandbox and lots, lots more. Pick up an instrument (or a sphere) and head on over.
Labels: carnival of space
Mars in Gemini with the Moon
Mars is the really dim dot above the Mon in this image taken this morning at 5:30 am. Click to embiggen and see some of the stars in Gemini Mars is near.On the 17th, the Moon will be close to Venus.
Labels: Mars, Moon, unaided eye observation
Sunday, September 13, 2009
Cosmic Diary - Magnetic fields
Cosmic Diary has a new feature article on Magnetic Fields by Thomas Dall of the European Southern Observatory
From the blurb:
From the blurb:
From fusion energy to life: magnetic fields, exoplanets, and the Earth
Magnetic fields within stars and extrasolar planets may seem like two totally separate topics, but as is often the case with astronomy, there are many surprising links. Join astronomer Thomas Dall as he explains how these two subjects help with his research.
Labels: International Year of Astronomy
Saturday, September 12, 2009
Seeing the Moon in Daylight.
The Moon in daylight. Left image, standard photo, right image, photo through polaroid glasses.
As long time readers of this blog know, I'm very enthusiastic about getting people to see Venus and Jupiter in the daylight. But did you know you can see the Moon in the daylight?
Now the dedicated astronomer types here will be going "What do you mean? Of course you you can see the Moon in daylight". Some others of you will remember a nearly full Moon rising just before sunset.
But many people have never noticed the Moon in the daytime sky. The Moon is a lot paler in the daytime sky, and can often be easily missed or or its pale aspect mistaken for a cloud. Also, for most of us living in suburban and urban settings , the sky is often a narrow band broken up by buildings or other obstructions, so seeing anything in the sky is a bit haphazard if you don't know where to look.
And of course there is clouds, we won't talk about clouds.
As well, when the Moon is at is largest, near full, it is only in the daytime sky for a short time, low to the horizon. Even today, as I write, the nearly last quarter Moon is low in the daytime sky, two hours after sunrise. Still, overall the Moon is visible in the daytime sky for a fair amount of time between full and three days before new Moon. You can actually see the crescent Moon two days before new, but it is very close to the Sun, and much care is needed (and often binoculars). In the past, I've had to use daylight Venus to help me find the thin crescent!
To find the Moon in the daylight it helps to have a good idea of where it is at night. After full it is relatively easy, you can see where the Moon is just before Sunrise, and can keep an eye on it after Sunrise. In the daylight, a lot of the moons features are easier to see with the unaided eye, as they are not lost in the glare of the Moons brightness. You can use polaroid glasses or filters to help see the Moon. Unlike Venus, whose light is strongly polarised, using polaroid filters cam increase the contrast between the Moon and the sky quite significantly (the images above don't do the actual increase justice).
Before full, you can use a newspapers Moon rise and set times (often up the back) or set of astronomical tables (or tide time tables) to find when the Moon rises, and scan the sky (wearing polaroid glasses if you like) for the Moon. Or you could see where the Moon is the previous night just after sunset, then, remembering that the Moon is around two hand spans further on each night, look in the approximate position the Moon was the next day (but two hand spans over).
We often think that astronomical activities cease when the Sun rises, but for the Moon and bright planets, it's not really over. Happy Moon hunting!
This is the fifth of a planned series of posts on looking at the sky and how to find your way around it as a beginner.
First post: The Dark Adapted Eye.
Second post: Let the Moon be Your Guide
Third Post: Seeing the Emu.
Fourth Post: Cloudy, Cloudy Sky
Labels: Astronomy, Daylight, Moon, unaided eye observation, where to look
Friday, September 11, 2009
NASA Images
Here's something you all (especially educators) might find very useful. NASA Images
is a repository of NASA media that would be very useful to educators, scientists, researchers, and space enthusiasts of all stripes. It is the largest collection of NASA media (still images, video & audio) available from a single, searchable site.
The images are tagged, come with descriptions and can be viewed and zoomed on screen or downloaded for later use. Goand have a play, then use the site to get someone excited about space and astronomy.
is a repository of NASA media that would be very useful to educators, scientists, researchers, and space enthusiasts of all stripes. It is the largest collection of NASA media (still images, video & audio) available from a single, searchable site.
The images are tagged, come with descriptions and can be viewed and zoomed on screen or downloaded for later use. Goand have a play, then use the site to get someone excited about space and astronomy.
Labels: astrophotography, education
So much for that Occultation
The Moon looked really impressive rising through the cloud just above the horizon, but I sure a heck wasn't seeing any Pleiades. Anyone out there have a better experience?
Labels: clouds, Occultation
Thursday, September 10, 2009
Hubble Beyond Amazing
Starbirth in the Eta Carina Nebula. Image Credit Hubble- NASA.So, if you have been living under a rock, in a cave, with earmuffs on, you will not know that NASA have released amazing images from the refurbished Hubble telescope. The Bad Astronomer has interesting details and pictures, Tom has his favourite shot, and Starts with a Bang has a nice paean to the Hubble instrumentation.
Labels: Astronomy, astrophotography, hubble
The Results of the Big Aussie Starhunt are Here
The Big Aussie Starhunt is over, and the results are in. First up, the "What constellation would you rename" competition was won by Madison Hunt, who wanted to rename Ara Echidna. Go to the competition website to find out why, and who the Schools winner was. Want to know what the skies around Australia are like, see the results site and find out who your city/town/region compares. Some weod places turn out bright, like Strathalban, way out in the country, had a limiting sky magnitude of 5!
Labels: Astronomy, light pollution
Further Update on Cosmic Chocolate
You may, or may not, remember this article about an edible version of the solar system available in Japan, or its follow up.Correspondent Cynthia Ma promised that next time she was in Osaka she would look up the hotel that was selling these delights, and try them out.
We she did. She reports that she did munch the whole solar system! And she is delighted to report that the yummiest of all is the Earth (lychee liqueur)!
Labels: Cynthia Ma, miscelaneous
Wednesday, September 09, 2009
Occultation of the Pleiades, Friday September 11 2009
A binocular view of the Moon in the Pleaides as seen from Darwin on the morning of September 11 at 00:11 am local time.In the early hours of the morning of September 11 (between just after midnight to just before 1 am, depending on where you live, see below) the Moon will pass through the Pleiades cluster, occulting several stars, some bright (ish), most very faint.
The best views will be in northern Australia (Darwin, Cairns, Cape York, some parts of northern WA such as Kurunurra) where Maia, Tayageta and Sterope are occulted), with Alice Springs, Weipa Mt Isa, Rockhampton etc. having good views (Tayageta, Sterope and 18 Tauri occulted). The rest of Australia except most of WA and Tasmania, which miss out, just gets to see 18 Tauri occulted (as a brightish star, there's also a host of dim ones)
Occultation path of Tayageta. Image credit IOTA.
The occultations start really close to the horizon, so you will need a clear level north eastern horizon to see this best. Even though nominally visible to the unaided eye, you will really need binoculars or a small telescope to get the most from this occultation.
For example, in Alice Springs Tayageta is revealed at 23:57 on the 10th, when the Moon is just two finger widths above the horizon. 18 Tauri is revealed at 00:01 on the 11th, when the Moon is just 3 finger widths above the horizon and Sterope is revealed at 00:18 when the Moon is a hand span from the horizon. For Carins, Rockhampton and Townsville Tayageta is revealed when the Moon is about two hand spans above the horizon (at 00:31, 00:11 and 00:28 am respectively).
For more information and times for your local areas see the Southern Skywatch occultation table. Alternatively, for northern Australia see the IOTA pages for Maia and Tayageta for occultation times in Universal Time.
Labels: Occultation, Pleiades
Tuesday, September 08, 2009
Carnival of Space #119 is here.
Carnival of Space #119 is is now up at the Planetary Society blog. There's the most distant black hole, celestial graffiti, amateurs lending science a hand, our minimal solar minimum, space-based power, water-cress as future astronaut food and much, much more. Leave your parking orbit and head on over.
Labels: carnival of space
The Sky This Week - Thursday September 10 to Thursday September 17
The Last Quarter Moon is Saturday September 12. Mercury is visible low in the evening twilight. Jupiter is visible the whole night and is easily seen as the brightest object in the sky. In the morning, Venus and Mars are seen above the eastern horizon before dawn, and are visited by the crescent Moon. In the early morning of Friday September 11 the Moon passes through the Pleiades.
Evening sky looking west at 6:30 pm local time on Sunday September 13. Click to embiggen.
The Last Quarter Moon is Saturday September 12.
Mercury is becoming more difficult to see in the western evening twilight(see diagram left). Mercury is below the bright star Spica and is rapidly lowering towards the horizon. By the end of the week it will be almost impossible to see.
Saturn is no longer visible, immersed in the twilight glow.
Jupiter is visible the whole night and is easily seen as the brightest object in the sky. While Jupiter is past opposition, where it is biggest and brightest as seen from Earth, it is still more than big enough to be appreciated in even the smallest telescope. If you don't have a telescope to view Jupiter, why not go to one of your local Astronomical Societies or Planetariums open nights? Jupiter's Moons are readily visible in binoculars or a small telescope. On Thursday September 10 and Saturday September 12 Jupiter has an interesting alignment of Moons.
Eastern horizon with Venus and the Moon at 5:30 am local time on Thursday morning September 17, click to embiggen.
In the morning, Venus and Mars are readily visible in the eastern sky. Red Mars is in the constellation of Gemini. On Monday September 14 the crescent Moon is just below Mars.
Bright white Venus is close to the horizon, but is still readily visible in the dawn twilight if you have a clear, unobstructed horizon. On Thursday September 17 Venus is near the crescent Moon. During the week Venus comes closer to the horizon.
In between September 14 and 17 the alignment of Mars and Venus with the waning crescent Moon will also be attractive.
A binocular view of the Moon in the Pleaides as seen from Darwin on the morning of September 11 at 00:11 am local time.
In the early hours of the morning of September 11 (between just after midnight to just before 1 am, depending on where you live) The Moon will pass through the Pleiades cluster, occulting several stars, so bright, most very faint. The best views will be in northern Australia (Darwin, Cairns, Cape York). For more information and times for your local areas see the Southern Skywatch occultation table.
Printable PDF maps of the Eastern sky at 10 pm, Western sky at 10 pm. For further details and more information on what's up in the sky, see Southern Skywatch. Cloud cover predictions can be found at SkippySky.
Evening sky looking west at 6:30 pm local time on Sunday September 13. Click to embiggen.The Last Quarter Moon is Saturday September 12.
Mercury is becoming more difficult to see in the western evening twilight(see diagram left). Mercury is below the bright star Spica and is rapidly lowering towards the horizon. By the end of the week it will be almost impossible to see.
Saturn is no longer visible, immersed in the twilight glow.
Jupiter is visible the whole night and is easily seen as the brightest object in the sky. While Jupiter is past opposition, where it is biggest and brightest as seen from Earth, it is still more than big enough to be appreciated in even the smallest telescope. If you don't have a telescope to view Jupiter, why not go to one of your local Astronomical Societies or Planetariums open nights? Jupiter's Moons are readily visible in binoculars or a small telescope. On Thursday September 10 and Saturday September 12 Jupiter has an interesting alignment of Moons.
Eastern horizon with Venus and the Moon at 5:30 am local time on Thursday morning September 17, click to embiggen.In the morning, Venus and Mars are readily visible in the eastern sky. Red Mars is in the constellation of Gemini. On Monday September 14 the crescent Moon is just below Mars.
Bright white Venus is close to the horizon, but is still readily visible in the dawn twilight if you have a clear, unobstructed horizon. On Thursday September 17 Venus is near the crescent Moon. During the week Venus comes closer to the horizon.
In between September 14 and 17 the alignment of Mars and Venus with the waning crescent Moon will also be attractive.
A binocular view of the Moon in the Pleaides as seen from Darwin on the morning of September 11 at 00:11 am local time.In the early hours of the morning of September 11 (between just after midnight to just before 1 am, depending on where you live) The Moon will pass through the Pleiades cluster, occulting several stars, so bright, most very faint. The best views will be in northern Australia (Darwin, Cairns, Cape York). For more information and times for your local areas see the Southern Skywatch occultation table.
Printable PDF maps of the Eastern sky at 10 pm, Western sky at 10 pm. For further details and more information on what's up in the sky, see Southern Skywatch. Cloud cover predictions can be found at SkippySky.
Labels: weekly sky
Monday, September 07, 2009
Comet C/2006 W3 Christiensen in GRAS
Comet C/2006 W3 Christiensen is a nice little comet that is anomalously bright, it should be around magnitude 12 according to predictions, but is up around magnitude 9.W3 is well placed for observation at the moment, and the weather finally gave me a break. I took this image using the remote telescope GRAS 8 shortly after moonrise using a 120 second exposure and a luminance filter and 1x binning.
C/2006 W3 Christiensen is moving rather fast at the moment, which is why the image is elongated. I will try and see if I can stack shorter images if the weather is kind to me. In the meantime, have a look at these images here and here.
Labels: comets
Sunday, September 06, 2009
Fathers Day 2009
"That's a Space Worm and that's a meteor with fire shooting out and those are black holes" - Smallest OneFathers Day involved breakfast in bed (Juice and Penaut butter Toast, the Bettdeckererschnappender weisle was away with her choir, so the boys had to do everything themselves - a cup of tea was out as Middle One was unsure what tae I liked, and didn't want to handle boiling water). Followed by presents (mostly chocolate and one complicated electronic item), followed by me trying to make complicated electronic item work.
"Am I really the Best Dad in the World?""No, but "better than a lot of dad's but not as good as some dad's" looks pretty silly on a card". - Middle One (budding comedy genius)
When the Bettdeckererschnappender weisle came home, we all went for a walk on the beach and tried to fly our kite.
Couldn't ask for a better Fathers Day, really.
Labels: home life, miscelaneous
Stunning Perseid Images
The Perseids are over, and the IMO records a quite nice outburst this year, with three peaks! Over in Ontario, Canada, Pierre Martin took some astounding photos, see here, here and most especially here.
Labels: astrophotography, Meteors
Saturday, September 05, 2009
From eccentric to well behaved - Are there invisible companions to known exoplanets
The 373 exoplanets we have discovered so far are a strange bunch. Mostly way larger than Jupiter, around 40% scream around their stars closer than Mercury orbits our sun. This is probably mostly due to detection bias, as we find most of the exoplanets by detecting tiny (really, really tiny) wobbles in their parent stars orbits. Detecting a planet of Jupiters size in Jupiters orbit would take many years of close scrutiny. As well as the sizes and locations, many of the exoplanets have strange (at least from our perspective) orbits. All planets have eliptical orbits. But while in our solar system most of the plants have orbits that are quite close to circular (see image top left) many extrasolar systems have orbits that are far more eccentric, almost cometary (see the system for Mu Ara above right)
Now, the weird orbits may be a result of how the super Jupiyters get close to their stars. We believe that latge, Jupiter -like planets form far from their stars, and then migrate in by interaction with other planets (Hot Jupiters have probably ejected any Earth mass planets from the stars equivalent of the inner solars system).This series of cosmic billiards may leave the hot Jupiters with very elongated, comet like orbits.
However, as for most of the planets, we are inferring the orbits from tiny wobbles, there may be some error in deriving these orbits, especially for orbits of single planets that are only mildly eccentric (see HIP 25110 above). A recent paper suggests that the gravitational tugs of unseen companions to known exoplanets could make their orbits appear more elliptical than they really are. The authors used a simulation where they generated a range of exoplanetary systems containing roughly equal numbers of single and double worlds. They then looked at the distribution of eccentricities in this simulated sky, and gfound that it matched the real distribution of eccentricities.
So what does this mean? It means that on average, about 4% of the known single exoplanets have unseen compaions. For single exoplantes with modest eccentricities, this probability is higher, around 12-16%.
So or solars systm is still unusual, but a little less unusual now,
WHICH RADIAL VELOCITY EXOPLANETS HAVE UNDETECTED OUTER COMPANIONS? Timothy J. Rodigas et al 2009 ApJ 702 716-723 doi: 10.1088/0004-637X/702/1/716 (pre-print here)
Labels: exoplanet, extrasolar planet, peer-reviewed research
Friday, September 04, 2009
Congratualtions Rob McNaught
Rob McNaught, discoverer of the famous magnificent comet McNaught (strictly comet 2006 P1 McNaught), has done it again. He's discovered another comet, C2009 Q5 (McNaught). However, this comet is special as this is Rob's 50th comet (does this make it a golden comet?). You can see images of the comet here and here.
Labels: comets
Thursday, September 03, 2009
Fear and Loathing in Vaccine Denial
Just to give you a feeling for the degree of misinformation presented on the Australian Vaccine Networks website, consider this entry on the Diphtheria Tetanus Pertussis Vaccine:
And most importantly, there is no Thiomersal in the modern vaccines. The Australian Vaccination Network uses fear inducing language (suffering and death, toxic) to scare people about vaccines which have prevented thousands of deaths and much suffering in Australia alone, without out indicating that these scare phrases don't even apply to the vaccines actually in use.
More mindbogglingly, from the 7:30 report transcript:
Pseudoscience peddlers who use scare tactics to frighten vulnerable people, families with young children, away from the simplest, most effective ways of controlling lethal infectious diseases are at the moment controlling our health. Be very, very afraid.
The pertussis or whooping cough vaccine has been cited as the cause of a great deal of suffering and death since the report by Madsen et al in 1933. Despite the more than 70 years ofcontroversy since that time, this vaccine continues to be used.Well, if you consider a serious adverse effect rate (encephalitis not death) of 0-10 incidents per million injections "a great deal of suffering" when compared to an actual death rate from pertussis infection at 1-3%. Of course, what the AVN doesn't mention is this is the old style vaccine, the new vaccines we use have a negligible serious adverse event rate.
All whole cell DTP vaccines contain mercury in the form of thiomersal. Mercury is one of the most toxic (poisonous) substances known to man and has been linked with forms of brain damage including Autism.Actually, while mercury is quite toxic, it is nowhere near as toxic as the pertussis toxin, which is 50% lethal at 429 or 546 ng per mouse, while Thiomersal is 50% lethal at 9 mg per mouse (the pertussis toxin is a million fold more lethal than mercury). As well, we have known that since medieval times that it is the dose that makes the poison, and the amount of Thiomersal in Thiomersal containing vaccines is negligible from a toxicity point of view. Thiomersal is NOT associated with autism. This has been shown again and again.
And most importantly, there is no Thiomersal in the modern vaccines. The Australian Vaccination Network uses fear inducing language (suffering and death, toxic) to scare people about vaccines which have prevented thousands of deaths and much suffering in Australia alone, without out indicating that these scare phrases don't even apply to the vaccines actually in use.
More mindbogglingly, from the 7:30 report transcript:
Meryl Dorey [of the Australian Vaccine network] says while Dana McCaffery's death was a tragedy, she rejects low vaccination rates played any part.This astounding statement shows complete ignorance of the way immunity works, if you drop the immunization rate, the degree of immune coverage falls below levels that can prevent transmission, and epidemics can explode, as they have done every time vaccination rates fell (eg the epidemic of pertussis in 1978-79 that produced 1000,000 cases and 36 deaths when vaccination rates fell).
The mother of four [Meryl Dorey] has written about her own family's experience with whooping cough, describing it as a storm in a teacup, which was treated with homeopathy.Great, just because they were lucky enough to have a mild case, they think the rest of the cases aren't a big deal. The major failure of logic here is unbelievable. And treating infectious disease with homeopathy, ineffective woo at its very best, makes me lost for words.
Pseudoscience peddlers who use scare tactics to frighten vulnerable people, families with young children, away from the simplest, most effective ways of controlling lethal infectious diseases are at the moment controlling our health. Be very, very afraid.
Labels: miscelaneous, Pseudoscience, vaccines
Vaccine Fears and the Whooping Cough Epidemic
Last night I watched the 7:30 report on the whooping cough epidemic in New South Wales. While the NSW one is the most serious, there are also epidemics in Victoria and Queensland.
What is appalling is that vaccination rates have fallen below unsustainable levels, at least in part due to the actions of the antivaccination group the Australian Vaccine Network spreading fear and disinformation. For example see the http://avn.org.au/library/index.php/vaccination-information/dtp.html site, where they raise the specter of thiomersal (thimerosal), even though it isn't in the majority of vaccines Australians would be exposed to, and even though thiomersal isn't a problem anyway see http://scienceblogs.com/insolence/2007/06/the_autism_omnibus_when_you_dont_have_sc.php and http://scienceblogs.com/angrytoxicologist/2007/10/thimerosal_better_late_than_ne.php.
Obviously governmental sources are not able to combat this disinformation. I can (and will) start my own blogging campaign to try and address the issues but given my (and others) experience in the long term fight against creationism and HIV denialism, I have little hope I can make a big impact even if high profile pro-science bloggers have had little impact on the Australian conciousness ( see Respectful Insolence as a prime example ). Still, as one of the hats I wear professionally is that of toxicologist, and as the anti-vaccination movement relies on an inchoate fear of "toxins", I'll do my best. In this day and age kids shouldn't be dying of preventable diseases like Whooping Cough.
What is appalling is that vaccination rates have fallen below unsustainable levels, at least in part due to the actions of the antivaccination group the Australian Vaccine Network spreading fear and disinformation. For example see the http://avn.org.au/library/index.php/vaccination-information/dtp.html site, where they raise the specter of thiomersal (thimerosal), even though it isn't in the majority of vaccines Australians would be exposed to, and even though thiomersal isn't a problem anyway see http://scienceblogs.com/insolence/2007/06/the_autism_omnibus_when_you_dont_have_sc.php and http://scienceblogs.com/angrytoxicologist/2007/10/thimerosal_better_late_than_ne.php.
Obviously governmental sources are not able to combat this disinformation. I can (and will) start my own blogging campaign to try and address the issues but given my (and others) experience in the long term fight against creationism and HIV denialism, I have little hope I can make a big impact even if high profile pro-science bloggers have had little impact on the Australian conciousness ( see Respectful Insolence as a prime example ). Still, as one of the hats I wear professionally is that of toxicologist, and as the anti-vaccination movement relies on an inchoate fear of "toxins", I'll do my best. In this day and age kids shouldn't be dying of preventable diseases like Whooping Cough.
Labels: miscelaneous, Pseudoscience, vaccines
Wednesday, September 02, 2009
Ice in Space turns 5!
IceInSpace, an Australian Astronomical Community website, turns 5 on September 13th, 2009. There's a competition, so why not drop in and have a look?
Labels: Astronomy, miscelaneous
A Martian Sunset
Corresponent Hugh Lovesy has made a movie of a recent (August 21) sunset on Mars from single blcck and white photos from Spirit (Hugh thanks Steve Squyres, Jim Bell and NASA et al for the originals). It's terrific! Click the link and be awed.
http://www.youtube.com/watch?v=O9ro60h1T_A
I look forward to more animations from Hugh.
http://www.youtube.com/watch?v=O9ro60h1T_A
I look forward to more animations from Hugh.
Tuesday, September 01, 2009
Carnival of Space #118 is here.
Carnival of Space #118 is now up at Cumbrian Sky. Aside from the host being located in the birthplace of the famous astronomer Sir Arthur Eddington, this carnival boasts an amazing series of MRO images processed by our host. As well, there's lasers in space, finding fractals, funny business at the IAU, fog on Titan, the Wide-field Infrared Survey Explorer, the 10th anniversary of Chandras first light and much, much more. Go walk ver in the gloaming and have a read.
Labels: carnival of space
The Sky This Week - Thursday September 3 to Thursday September 7
The Full Moon is Saturday September 5. Mercury is visible in the evening twilight, while Saturn is lost in the twilight. Jupiter is visible the whole night and is easily seen as the brightest object in the sky. In the morning, Venus and Mars are seen above the eastern horizon before dawn.
Evening sky looking west at 7:00 pm local time on Thursday September 3. Click to embiggen.
The Full Moon is Saturday September 5.
Mercury starts off easily visible in the western evening twilight below the bright star Spica (see diagram left). Mercury rapidly lowers towards the horizon, becoming much harder to see.
Saturn is just visible in the early evening twilight just above above the north-western horizon. During the week it vanishes into the twilight glow.
Jupiter is visible the whole night and is easily seen as the brightest object in the sky. While Jupiter is past opposition, where it is biggest and brightest as seen from Earth, it is still more than big enough to be appreciated in even the smallest telescope. If you don't have a telescope to view Jupiter, why not go to one of your local Astronomical Societies or Planetariums open nights? Jupiter's Moons are readily visible in binoculars or a small telescope. On Thursday September 10 Jupiter has an interesting alignment of Moons.
Eastern horizon with Mars and Venus at 5:30 am local time on Thursday morning September 3, click to embiggen.
In the morning, Venus and Mars are readily visible in the eastern sky. Red Mars is below the the constellation of Orion and forms a elongated triangle with two bright red stars Aldebaran and Betelguese in Orion. On Thursday September 3 Mars is very near µ Geminorum.
Bright white Venus is close to the horizon, but is still readily visible in the dawn twilight. On Thursday September 3 Venus is near the Beehive cluster in Cancer. This will be difficult to observe, being close to the horizon, but with good binoculars this should be a splendid sight. During the week Venus comes closer to the horizon.
Printable PDF maps of the Eastern sky at 10 pm, Western sky at 10 pm. For further details and more information on what's up in the sky, see Southern Skywatch. Cloud cover predictions can be found at SkippySky.
Evening sky looking west at 7:00 pm local time on Thursday September 3. Click to embiggen.The Full Moon is Saturday September 5.
Mercury starts off easily visible in the western evening twilight below the bright star Spica (see diagram left). Mercury rapidly lowers towards the horizon, becoming much harder to see.
Saturn is just visible in the early evening twilight just above above the north-western horizon. During the week it vanishes into the twilight glow.
Jupiter is visible the whole night and is easily seen as the brightest object in the sky. While Jupiter is past opposition, where it is biggest and brightest as seen from Earth, it is still more than big enough to be appreciated in even the smallest telescope. If you don't have a telescope to view Jupiter, why not go to one of your local Astronomical Societies or Planetariums open nights? Jupiter's Moons are readily visible in binoculars or a small telescope. On Thursday September 10 Jupiter has an interesting alignment of Moons.
Eastern horizon with Mars and Venus at 5:30 am local time on Thursday morning September 3, click to embiggen.In the morning, Venus and Mars are readily visible in the eastern sky. Red Mars is below the the constellation of Orion and forms a elongated triangle with two bright red stars Aldebaran and Betelguese in Orion. On Thursday September 3 Mars is very near µ Geminorum.
Bright white Venus is close to the horizon, but is still readily visible in the dawn twilight. On Thursday September 3 Venus is near the Beehive cluster in Cancer. This will be difficult to observe, being close to the horizon, but with good binoculars this should be a splendid sight. During the week Venus comes closer to the horizon.
Printable PDF maps of the Eastern sky at 10 pm, Western sky at 10 pm. For further details and more information on what's up in the sky, see Southern Skywatch. Cloud cover predictions can be found at SkippySky.
Labels: weekly sky
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