The small dot above the star 1RSX J160929.1-210524 is a likely ~8 Jupiter-mass companion. Credit: Gemini Observatory
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Astronomers have unveiled what is likely the first picture of a planet around a normal star similar to the Sun. Using the Gemini North telescope on Mauna Kea in Hawaii, astronomers from the University of Toronto imaged the young star 1RXS J160929.1-210524, which lies about 500 light-years from Earth and a candidate companion of that star. They also obtained spectra to confirm the nature of the companion, which has a mass about eight times that of Jupiter, and lies roughly 330 times the Earth-Sun distance away from its star. For comparison, the most distant planet in our solar system, Neptune, orbits the Sun at only about 30 times the Earth-Sun distance. The parent star is similar in mass to the Sun, but is much younger. “This is the first time we have directly seen a planetary mass object in a likely orbit around a star like our Sun,†said David Lafrenière, lead author of a paper detailing the discovery. “If we confirm that this object is indeed gravitationally tied to the star, it will be a major step forward.â€
Until now, the only planet-like bodies that have been directly imaged outside of the solar system are either free-floating in space (i.e. not found around a star), or orbit brown dwarfs, which are dim and make it easier to detect planetary-mass companions.
The existence of a planetary-mass companion so far from its parent star comes as a surprise, and poses a challenge to theoretical models of star and planet formation. “This discovery is yet another reminder of the truly remarkable diversity of worlds out there, and it’s a strong hint that nature may have more than one mechanism for producing planetary mass companions to normal stars,†said team member Ray Jayawardhana.
The team’s Gemini observations took advantage of adaptive optics technology to dramatically reduce distortions caused by turbulence in Earth’s atmosphere. The near-infrared images and spectra of the suspected planetary object indicate that it is too cool to be a star or even a more massive brown dwarf, and that it is young.
While it could be a chance alignment between the object and the young star, it will take up to two years to verify that the star and its likely planet are moving through space together. “Of course it would be premature to say that the object is definitely orbiting this star, but the evidence is extremely compelling. This will be a very intensely studied object for the next few years!†said Lafrenière.
Team member Marten van Kerkwijk described the group’s search method. “We targeted young stars so that any planetary mass object they hosted would not have had time to cool, and thus would still be relatively bright,†he said. “This is one reason we were able to see it at all.â€
The Jupiter-sized body has an estimated temperature of about 1800 Kelvin (about 1500ºC), much hotter than our own Jupiter, which has a temperature of about 160 Kelvin (-110ºC), and its likely host is a young star of type K7 with an estimated mass of about 85% that of the Sun.
“This discovery certainly has us looking forward to what other surprises nature has in stock for us,†said Van Kerkwijk.
Map projected images of lake-effect clouds at the winter north pole of Titan from the VIMS (left, both from 27 April 2007) and ISS (right, from 24 Feb 2007, top, and 13 April 2007, bottom) imagers on board the Cassini spacecraft.
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While browsing through Cassini images of Saturn’s moon Titan, astronomer Mike Brown and some colleagues noticed a recurring pattern of clouds appearing over the frigid moon’s north pole. While a large, stable cloud has been visible in every image of Titan’s north pole obtained since its discovery, Brown noticed bright “knots or streaks” in the cloud that appeared on some images but not others, or changed in images taken hours apart. Brown thought these bright features looked similar to cumulus clouds – or even like thunderheads. But how could tropical-like thunderheads be present on a moon where surface temperatures hover around -178°C (-289°F)? Brown believes these clouds are similar to winter-time lake-effect clouds found on Earth, and are due to convection and condensation occurring in the methane and ethane lakes on Titan.
“On the Earth, lake-effect clouds occur in the winter when cold air goes over warm water (like the Great Lakes) and picks up heat and moisture and then, often, deposits it all in the form of snow on the eastern shores,” Brown told Universe Today. “On Titan the winters are so long (the north pole has been in the dark for the past ~10 years!) that the lakes retain almost no heat. But as the spring sunlight starts to hit the lakes they begin to heat up just a tiny amount and this is enough to cause little blips of evaporation and clouds.”
So, while lake-effect clouds on Earth are predominantly a winter event, on Titan, lake-effect clouds occur as spring is approaching. The clouds appear only in images taken since February 2005, as the increasing amount of sunlight has heated the liquid hydrocarbon lakes slightly and evaporation takes place. “Every time the lakes warm up just a bit, a huge dollop of evaporation occurs, which re-cools the lake, and we see a cumulus cloud pop up. The lake then has to wait for some more sunlight before it happens again,” Brown wrote in his blog.
Brown, a professor of planetary astronomy at Caltech, is known primarily for his discoveries of trans-Neptunian objects like Eris and Sedna. But he enjoys dipping his toes in the water, so to speak, in other areas as well. That includes studying the meteorology of a moon that’s over 1,200 million kilometers away. “I think it’s pretty fun,” Brown admitted.
Since spring is approaching on Titan (equinox occurs in August 2009), the cloud activity is likely to increase. Fortuitously, Cassini is scheduled to fly by Titan frequently the next few years, and Brown and his team will be keeping an eye on these lake-effect-like clouds that may have a great influence on Titan’s weather.
“When Cassini was first conceived no one even knew that clouds existed on Titan!” said Brown. “But the trick is to put a spacecraft up that has highly versatile and flexible instruments and then you’ll be able to see things even if you hadn’t anticipated them.”
Brown and his team examined the north polar clouds of Titan using data from VIMS (Visible and Infrared Mapping Spectrometer) and ISS (Imaging Science Subsystems) instruments on board the Cassini spacecraft and from adaptive optics observations from the Gemini observatory and full-disk spectroscopy of Titan from the NASA Infrared Telescope Facility (IRTF).
Titan continues to surprise planetary scientists like Brown. “I love the similarities and differences with the Earth,” he said. “Titan is the only other place that we know of that has both liquids on its surface and a thick atmosphere, so we get a chance to watch something sort of Earth-like but with some very non-terrestrial behavior.”
Known as Caldwell 20 to some, NGC 7000 to others and the North America Nebula to most, this diffuse emission/reflection nebula near Deneb can frequently be seen by the unaided eye from a dark location, but the sheer size of this 1600 light year distant gas cloud often confuses people as to the reality of what they are seeing. Let’s take a look at just a few of the bricks in the “Wall”..
Hey you, out there beyond the wall… Is there anybody out there?
In this image taken by Kent Wood, we are looking a just a close-up of the region shaped like the Gulf of Mexico and often referred to as the “Cygnus Wall”. It is here that light from young, energetic stars is taking the surrounding cold gas fields and warming them, causing an ionization front to form – filled with dense and delightfully delicate filaments. This highly energized “shock front” stands out in bold relief against the complex dark gases and streaking dark dustlanes.
What shall we use… To fill the empty spaces? What shall we use… To complete the wall?
Let’s try star formation, eruptive variables, flare stars and T-Tauri types. According to G.W. Marcy: “A slitless spectrographic search for H..cap alpha.. emission stars in NGC 7000 has revealed 18 new examples, most of which are presumably T Tau stars. An examination of all known T Tau stars in these fields has uncovered no events of the FU Ori type, except for that of V1057 Cygni.” All of these make themselves at home in the warm ionized gas in the local interstellar medium. However, it is the properties of this ionized gas that are so curious to study. In this case, in the faint optical emission lines of hydrogen alpha.
Hey you, don’t help them to bury the light…
Along the bright rim of the wall is where the action is at. According to the work of Koji (et al), it is here where most of the star forming action is going on. “We have found small clusters of near-infrared sources having young stellar object (YSO) colors in some of these objects; most of the cluster members are considered to be older than the IRAS point sources and to be pre–main-sequence stars such as T Tauri stars. In at least six bright-rimmed clouds, the clusters are elongated toward the bright-rim tip or the exciting star(s) of the bright rim with the IRAS sources situated near the other end. There is a tendency for bluer (i.e., older) stars to be located closer to the exciting star(s) and for redder (i.e., younger) stars to be closer to the IRAS sources. This asymmetric distribution of the cluster members strongly suggests small-scale sequential star formation or propagation of star formation from the side of the exciting star(s) to the IRAS position in a few times 105 yr, as a result of the advance of the shock caused by the UV radiation from the exciting star(s).”
And all in all it was just a brick in the wall…
But some of the true beauty is the dust and soot laced clouds filled with PAHs. We learned about those Polycyclic Aromatic Hydrocarbons, not long ago and just what they mean. And, we know the Cygnus X region is one of the richest star formation sites in the Galaxy. But what about this structure? This Wall?
The Wall- NGC 7000 (Panorama) by Kent Wood
A distant ship, smoke on the horizon…. You are only coming through in waves.
Believe it or not, NGC 7000 was imaged from the lunar surface during the 1972 Apollo 16 mission and continues to be studied for its polarization properties and scattering in h-alpha wavelengths. It has even had its electron temperature taken to prove that interstellar dust is masking the light we see. However, what we do see may be an illusion. From the studies of R.J. Reynolds; “According to photoionization models of the warm ionized medium, these [O i]/Ha ratios suggest that most of the Ha originates from density-bounded, nearly fully ionized regions along the lines of sight rather than from partially ionized H i clouds or layers of H ii on the surfaces of H i clouds.”
Hey you, out there beyond the wall… Is there anybody out there?
Venture into the dark cloud and find out. According to Laugalys (et al) “Magnitudes and color indices of 430 stars down to V Ëœ 17.5 mag in the eight-color Vilnius + I photometric system were obtained in four areas of diameter 20′ within the dark cloud L935 separating the North America and Pelican nebulae. Spectral types, interstellar color excesses, extinctions and distances of stars were determined from the photometric data. The plot of extinction vs. distance shows that the dark cloud begins at a distance of 520±50 pc. About 40 stars in the cloud, mostly K and M dwarfs, are suspected to have Hα emission; these stars also exhibit infrared excesses. Four of them are known pre-main-sequence stars. Our star set contains J205551.3+435225 (V = 13.24) which, according to Camerón and Pasquali (2005), is the O5 V type star ionizing the North America and Pelican nebulae. If this spectral type is confirmed, the star would have an extinction AV between 9 and 10 magnitudes (depending on the accepted extinction law) and a distance which is not very different from the dust cloud distance.”.
How shall I fill the final places? How should I complete the wall?
I guess the last words would be the illuminating source. In a study done by Comerón and Pasquali; “We present the results of a search for the ionizing star of the North America (NGC 7000) and the Pelican (IC 5070) nebulae complex. The application of adequate selection criteria to the 2MASS JH KS broad-band photometry allows us to narrow the search down to 19 preliminary candidates in a circle of 0o 5 radius containing most of the L935 dark cloud that separates both nebulae. Follow-up near-infrared spectroscopy shows that most of these objects are carbon stars and mid-to-late-type giants, including some AGB stars. Two of the three remaining objects turn out to be later than spectral type B and thus cannot account for the ionization of the nebula, but a third object, 2MASS J205551.25+435224.6, has infrared properties consistent with it being a mid O-type star at the distance of the nebulae complex and reddened by AV ≃ 9.6. We confirm its O5V spectral type by means of visible spectroscopy in the blue. This star has the spectral type required by the ionization conditions of the nebulae and photometric properties consistent with the most recent estimates of their distance. Moreover, it lies close to the geometric center of the complex that other studies have proposed as the most likely location for the ionizing star, and is also very close to the position inferred from the morphology of cloud rims detected in radio continuum. Given the fulfillment of all the conditions and the existence of only one star in the whole search area that satisfies them, we thus propose 2MASS J205551.25+435224.6 as the ionizing star of the North America/Pelican complex.”
All in all… It’s just another brick in the wall.
We would like to thank AORAIA member, Kent Wood for the splendid image and the great research challenge!
I like using binoculars… and I like using a telescope. So what happens when you combine both? For savvy telescope users, the result is called a binoviewer – but using one can sometimes introduce problems. Dark images, fast focal ratio telescopes, problems with focusing and outright expense… But can these problems be overcome in a binoviewer that’s easy to afford, works with all telescopes, doesn’t cost an arm and a leg and is high quality? The answer is yes…
Say hello to the William Optics Binoviewer.
At first I really wasn’t very interested in working with a binoviewer because the 3D effect definitely throws my mind a curve when studying at the telescope. Oh, yes. I had all kinds of excuses. More difficulty focusing with one eye than another, my favorite scope has a fast focal ratio, I use reflectors… You name it. But William Optics changed my mind.
When I opened the well-made little carton with it’s pretty embossed logo, I was stunned at the craftsmanship. Pictures do not do it justice. The William Optics Binoviewers are very precision in appearance with sterile white powder coat paint, heavy – but not too heavy, big, easy-to-grip thumbscrews and brass compression ring fittings for the eyepieces. Instead of needing to purchase two additional eyepieces, it comes already equipped with twin William Optics Wide Angle (66º) 20mm occulars. Just to state a case in point here, I know for a fact these two eyepieces alone are worth more than half of what the binoviewers cost! But, back to the task in hand…
The William Optics Binoviewers spread easily to accommodate interpupillary distance and each eyepiece holder has its own separate helical focuser. What’s more – and this is a feature that sets them apart – they come already equipped with a 1.6X barlow nosepiece. What’s inside? According to the manufacturer specs, we’re talking about a true BaK4 prism with a genuine 20.2mm of clear aperture. So what does terms like that mean to just the average Joe? It means we aren’t talking about a pair of binoviewers that are going to lay around in your eyepiece case because they deliver cruddy images… We’re talking about a class act.
I’m not exactly sure what makes the William Optics Binoviewers work so well, maybe it’s the 4″ optical path, but whatever it is, they are unlike any inexpensive binoviewers I’ve ever used. Combine it with a h-alpha solar telescope and once you’re in tune you’ll get an image that will blow your mind. Put it in a refractor telescope and go for Jupiter… the effect of sheer dimensionality and being able to tell distance in the galiean moons will make you a planetary observer. Use it in your workhorse reflector and study the Moon. You’ll feel like you’re there, dude. Drop the binoviewer into a big dob and check out something familiar – like the M27. Holy guacamole… It looks like something you’d see in an IMAX theatre! Put it in a little rich field telescope and look at a star cluster… You can see the light years between the stars. Put it in an observatory telescope and look at a galaxy?
And you’ll become a believer.
How do I feel about the William Optics Binoviewer now? While it may never surpass the Denkmeier or Bino Vue in some folks opinion, it’s not going to take part of your life savings to afford and you won’t regret the purchase. As far as compatibility goes, it worked with every telescope I happen to own and provided sharp clarity, bright images and an absolutely stunning three-dimensional effect on every object I chose. For $199 you get the complete package and no surprises. You won’t need to buy eyepieces, adapters or a special nosepiece – it works with any 1.25″ focuser and probably any telescope you choose to put it in. Small wonder I’ve never heard anyone say anything bad about William Optics Binoviewers…
They’re a real class act.
We would like to thank Oceanside Photo and Telescope for providing the William Optics Binoviewers for this product review. If you’re interested in purchasing a pair of William Optics Binoviewers from OPT, please remember to put “Universe Today Astronomers” in the club affiliation box when you check out to receive your special UT discount on your final bill!
Sun with a huge coronal mass ejection. Image credit: NASA
There are so many beautiful pics of the Sun, it’s almost too difficult to know where to start.
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This is a picture of the Sun captured by NASA’s SOHO spacecraft. It would be a typical day on the Sun, except for the enormous coronal mass ejection blasting out of the upper right-hand side of the Sun. When the Sun is at its most active state, it can release 5-6 of these a day.
STEREO's image of the Sun. Image credit: NASA
This photograph of the Sun was one of the first captured by NASA’s STEREO mission. These twin spacecraft were launched in 2006. One is leading the Earth in orbit, while the other has fallen behind. With both observing the Sun, scientists are given a 3-dimensional view of the Sun.
Sun seen from TRACE. Image credit: NASA
This pic of the Sun shows our star on a calm day, believe it or not. When you look close, this is what the surface of the Sun is doing all the time. The TRACE spacecraft was launched in 1997, and helps scientists study the Sun’s magnetic field – and to take beautiful photos like this.
Ultraviolet view of the Sun. Image credit: SOHO
This picture of the Sun was captured by the EIT instrument on board the NASA/ESA SOHO spacecraft. It reveals the normally invisible ultraviolet radiation streaming from the Sun. It’s actually a composite of three different Sun photos captured at different parts of the ultraviolet spectrum and then merged together.
Picture of the Sun in 3-D. Image credit: NASA
You’re going to need a set of 3-D glasses to get the most out of this Sun photograph. It’s an image of Sun captured by NASA’s twin STEREO spacecraft. Images like this help scientists understand how the Sun interacts with its local environment, and better predict space weather.
You take your clock for granted today, but it’s only been in the last couple of centuries that machines (and electronics) have been accurate enough to be used for timekeeping. Before that, people had to use other ways to tell the time of day. One of the most useful and easy to make is a sundial.
In its simplest form, a sundial consists of a style – a thin rod or sharp straight edge – that casts a long shadow onto a flat surface. As the Sun moves in the sky, the shadow moves as well in a perfectly predictable way. By putting marks on the flat surface, you can know what time it is by the position of the shadow.
For a sundial to work, it must be aligned with the axis of the Earth’s rotation. The style must be pointed towards North, and the style’s angle with horizontal must be equal to the sundial’s latitude.
NASA’s Mars Exploration rovers are equipped with miniature sundials on top of their color calibration targets. Scientists use these to fix colors in images based on the known colors in these calibration targets. The sundials are decorative, but they also help locate the Sun’s direction compared to the rovers.
This article on Universe Today talks about the sundial attached to NASA’s Mars Exploration rovers.
Would you like to make your own sundial? NASA has a cool page that shows you how to construct and use your own sundial. This page gives you a template so you can construct your own sundial (warning, it’s a PDF document, not a web page).
We have recorded an episode of Astronomy Cast just about the Sun called The Sun, Spots and All.
Artist rendition of New Horizons in the Kuiper Belt. Credit: Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute (JHUAPL/SwRI)
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Still seven years away from its rendezvous with Pluto, the New Horizons spacecraft was awoken from hibernation for the second annual checkout of all systems. The spacecraft and its team back on Earth will also undergo three months of operations as the New Horizons will make observations of Uranus, Neptune, and Pluto. But the first order of business was uploading an upgraded version of the software that runs the spacecraft’s Command and Data Handling system. “Our ‘brain transplant’ was a success,†says New Horizons Principal Investigator Alan Stern. “The new software – which guides how New Horizons carries out commands and collects and stores data – is now on the spacecraft’s main computer and operating, over a billion miles from home!â€
The mission ops team at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, radioed the software load and the commands to start it earlier this week through NASA’s Deep Space Network of antennas to the spacecraft, now just more than 1.01 billion miles (1.62 billion kilometers) from Earth. In the next 10 days the team will beam up additional new software for both the spacecraft’s Autonomy and Guidance and Control systems.
Space Science Mission Operations Center at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland.
Alice Bowman, New Horizons mission operations manager at APL, says the spacecraft and its computers are healthy. “The new software fixes a few bugs and enhances the way these systems operate, based on what we’ve learned in running the spacecraft in the nearly three years since launch,†she says. “They also configure the onboard systems to be ready to support the Pluto-Charon encounter rehearsals scheduled for next summer.â€
New Horizons is more than 200 million miles beyond Saturn’s orbit and more than 11 astronomical units (1.02 billion miles) from the Sun, flying about a million miles per day toward Pluto. Annual Checkout 2 (ACO-2) continues through mid-December; follow its progress through frequent updates on the New Horizons Twitter page.
Position of the Sun in the Milky Way. Image credit: NASA
Everything’s orbiting something it seems. The Moon goes around the Earth, and the Earth orbits the Sun. But did you know that the Sun orbits the Milky Way galaxy?
Astronomers have calculated that it takes the Sun 226 million years to completely orbit around the center of the Milky Way. In other words, that last time that the Sun was in its current position in space around the Milky Way, dinosaurs ruled the Earth. in fact, this Sun orbit has only happened 20.4 times since the Sun itself formed 4.6 billion years ago.
Since the Sun is 26,000 light-years from the center of the Milky Way, it has to travel at an astonishing speed of 782,000 km/hour in a circular orbit around the Milky Way center. Just for comparison, the Earth is rotating at a speed of 1,770 km/h, and it’s moving at a speed of 108,000 km/h around the Sun.
It’s estimated that the Sun will continue fusing hydrogen for another 7 billon years or so. In other words, it only has another 31 orbits it can make before it runs out of fuel.
Are you interested in more articles about the Sun? We have written plenty for Universe Today. Here’s an article that shows how some stars take an erratic journey around the Milky Way, and another article about a ring of stars orbiting the Milky Way.
Here’s an article that describes the process astronomers used to determine the orbit around the Milky Way.
We have recorded an episode of Astronomy Cast just about the Sun called The Sun, Spots and All.
From the people that brought you the X PRIZE and the Google Lunar X PRIZE comes something new that’s a little more down to Earth. However they also say it’s crazy. But if you’re handy with a video camera, care about the environment, and are interested in winning a nice chunk of spare change, this might be up your alley. The $25,000 “What’s your crazy green idea?†Video Contest was just announced, and the X PRIZE folks are looking to find out what crazy ideas are out there that could become the next big thing for the environoment. “Before something is a breakthrough, it’s a crazy idea,” they say, and the X PRIZE Foundation is looking for your crazy green ideas to become the next X PRIZE. Here’s a video for more information:
Here are the rules:
1. Submit a 2 minute video to this group by October 31, 2008 explaining what you think should be the next Energy and Environment X PRIZE. Here’s the link.
2. The three most viable ideas will be posted on the X PRIZE website on November 15.
3. The public will be given two weeks to vote for the winner on the same site. The most creative, revolutionary idea and video will receive $25,000 and it could become the next great X PRIZE.
Be sure that your video answers the following questions:
1. What is the Grand Challenge or world-wide problem that you are trying to solve?
2. What is the specific prize idea (goal, rules, judging criteria)?
3. How will this prize lead to benefits for humanity?
Sun with a huge coronal mass ejection. Image credit: NASA
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We owe everything we have to the Sun. If it weren’t for the Sun, there’d be no life on Earth. The relationship between Sun and Earth has gone back for 4.6 billion years, and should last for another 7 billion years or so.
As you probably know, the Sun is just a giant sphere of gas. At the core of the Sun, huge quantities of hydrogen are squished together in the intense pressure and temperature of this extreme environment. Hydrogen is converted to helium, and this reaction releases a tremendous amount of energy.
How much energy? Astronomers calculate that there are 600 million tons of hydrogen fused every second. 4 million tons of matter is converted to pure energy every second. This releases 3.86×1026 joules of energy every second. Although most of this energy heads off into space, plenty still falls onto the Earth. In fact, there’s enough energy coming from the Sun to deposit 342 Watts of energy onto every square meter of the Earth (averaged over the year, over the whole planet).
From our perspective, Sun and Earth go hand in hand. This energy from the Sun heats up the planet, preventing us from cooling down to near absolute zero temperatures of space. Our atmosphere traps the energy as heat, keeping the whole planet a nice comfortable temperature.
Plants have been soaking up this energy for millions of years. When you burn gasoline in your car, it comes from oil, which is energy from the Sun that planets have been storing for millions of years.
Sun and Earth are locked in a gravitational dance as well. The mass of the Sun is 2 × 1030 kilograms. This is enough to reach out across space and keep the Earth (and the rest of the planets) locked in orbit around it. We even experience tides from the gravity of the Sun.
Were you wondering how far away the Earth is from the Sun? And the Sun isn’t always trying to help us. Sometimes it’s throwing monster flares at us as well.
