Posted on by Nancy Atkinson

Another Solar System Like our Own?

Artists impression shows the planetary system around the Sun-like star HD 10180. Credit: ESO/L. Calçada

There is another Sun-like star out there with an intriguing family of planets orbiting about and it could be the closest parallel to our own solar system that astronomers have found yet. European astronomers discovered a planetary system containing at least five planets, orbiting the star HD 10180, with evidence that two other planets may be present. If confirmed, one of those would have the lowest mass ever found.

“We have found what is most likely the system with the most planets yet discovered,” says Christophe Lovis, who led the team. “This remarkable discovery also highlights the fact that we are now entering a new era in exoplanet research: the study of complex planetary systems and not just of individual planets. Studies of planetary motions in the new system reveal complex gravitational interactions between the planets and give us insights into the long-term evolution of the system.”

To make this system even more intriguing, the team also found evidence that the distances of the planets from their star follow a regular pattern, as also seen in our Solar System. “This could be a signature of the formation process of these planetary systems,” said team member Michel Mayor.

HD 10180, is located 127 light years away in the southern constellation of Hydrus. The five confirmed planets are large, about the size of Neptune — between 13 and 25 Earth masses —with orbital periods ranging from between six and 600 days. The planets’ distances from the star ranges from 0.06 and 1.4 times the Earth–Sun distance.

A close-up of the sky around the star HD 10180. Credit: ESO and Digitized Sky Survey 2. Acknowledgment: Davide De Martin

“We also have good reasons to believe that two other planets are present,” said Lovis. One would be a Saturn-like planet (with a minimum mass of 65 Earth masses) orbiting in 2200 days. The other would be the least massive exoplanet ever discovered, with a mass of about 1.4 times that of the Earth. It is very close to its host star, at just 2 percent of the Earth–Sun distance. One “year” on this planet would last only 1.18 Earth-days.

“This object causes a wobble of its star of only about 3 km/hour— slower than walking speed — and this motion is very hard to measure,” says team member Damien Ségransan. If confirmed, this object would be another example of a hot rocky planet, similar to Corot-7b.

The team used the planet-finding HARPS spectrograph, attached to ESO’s 3.6-metre telescope at La Silla, Chile, and made observations of HD 10180 for six years.

The newly discovered system of planets around HD 10180 is unique in several respects. First of all, with at least five Neptune-like planets lying within a distance equivalent to the orbit of Mars, this system is more populated than our Solar System in its inner region, and has many more massive planets there. Furthermore, the system probably has no Jupiter-like gas giant. In addition, all the planets seem to have almost circular orbits.

With this new announcement, the total number of exoplanets found is 472.

The team’s paper was submitted to Astronomy and Astrophysics (“The HARPS search for southern extra-solar planets. XXVII. Up to seven planets orbiting HD 10180: probing the architecture of low-mass planetary systems” by C. Lovis et al.).

Source: ESO

Posted on by Spacevidcast

Dragon Drop Tests and Heat1X-Tycho Brahe Set to Launch – SpacePod 2010.08.24

Home made rockets launched from home made submarines next to dragon wings floating in the ocean on your SpacePod for August 24th, 2010

Before we begin I just wanted to give a shout out to our new viewers on both Space.com and Universe Today. Hopefully you like what you’ll see and you’ll stick around for a while, check out some of our other videos and join us for our live weekly show all about space. For today though, lets start over the Pacific Ocean where SpaceX tested the Dragon’s parachute deployment system on August 12th, 2010.
Continue reading “Dragon Drop Tests and Heat1X-Tycho Brahe Set to Launch – SpacePod 2010.08.24”

Posted on by Nancy Atkinson

Tight Binaries are ‘Death Stars’ for Planets

This plot of data from NASA's Spitzer Space Telescope tells astronomers that a dusty planetary smashup probably occurred around a pair of tight twin, or binary, stars. Image credit: NASA/JPL-Caltech/Harvard-Smithsonian CfA

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Astronomers studying double star systems where the two stars are extremely close have found a pattern of destruction. While there probably isn’t a Star Wars-like Death Star roaming the Universe, tight binary systems might provide the equivalent of Darth Vader’s favorite weapon. “This is real-life science fiction,” said Jeremy Drake of the Harvard-Smithsonian Center for Astrophysics. “Our data tell us that planets in these systems might not be so lucky — collisions could be common. It’s theoretically possible that habitable planets could exist around these types of stars, so if there happened to be any life there, it could be doomed.”

Using the Spitzer Space Telescope, Drake and his team spotted a surprisingly large amount of dust around three mature, close-orbiting star pairs, that might be the aftermath of tremendous planetary collisions.

Drake is the principal investigator of the research, published in the Aug.19 issue of the Astrophysical Journal Letters.

The particular class of binary stars in the study are extremely close together. Named RS Canum Venaticorums, or RS CVns for short, they are separated by only about 3.2-million kilometers (two-million miles ), or two percent of the distance between Earth and our sun. The binaries orbit around each other every few days, with one face on each star perpetually locked and pointed toward the other.

These stars are familiarly like our own Sun – about the same size and probably about a billion to a few billion years old — roughly the age of our sun when life first evolved on Earth. But these stars spin much faster, and, as a result, have powerful magnetic fields, and giant, dark spots. The magnetic activity drives strong stellar winds — gale-force versions of the solar wind — that slow the stars down, pulling the twirling duos closer over time.

This is not a good scenario for planetary survival.

As the stars cozy up to each other, their gravitational influences change, and this could cause disturbances to planetary bodies orbiting around both stars. Comets and any planets that may exist in the systems would start jostling about and banging into each other, sometimes in powerful collisions. This includes planets that could theoretically be circling in the double stars’ habitable zone, a region where temperatures would allow liquid water to exist. Though no habitable planets have been discovered around any stars beyond our sun at this point in time, tight double-star systems are known to host planets; for example, one system not in the study, called HW Vir, has two gas-giant planets.

“These kinds of systems paint a picture of the late stages in the lives of planetary systems,” said Marc Kuchner, a co-author from NASA Goddard Space Flight Center. “And it’s a future that’s messy and violent.”

The temperatures around these systems measured by Spitzer are about the same as molten lava. The astronomers says that dust normally would have dissipated and blown away from the stars by this mature stage in their lives. They conclude that something — most likely planetary collisions — must therefore be kicking up the fresh dust. In addition, because dusty disks have now been found around four, older binary systems, the scientists know that the observations are not a fluke. Something chaotic is very likely going on.

If any life forms did exist in these star systems, and they could look up at the sky, they would have quite a view. Marco Matranga, lead author of the paper, also from Harvard-Smithsonian said, “The skies there would have two huge suns, like the ones above the planet Tatooine in ‘Star Wars.'”

The research was published in the Aug.19 issue of the Astrophysical Journal Letters.

Source: JPL

Posted on by Nancy Atkinson

Astronomers Use Radio Signals for New Way to Weigh Planets

The Sun, Earth and Jupiter orbit a common barycentre. credit – D. Champion, MPIfR

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Finding the mass of other planets is tricky, and usually is done by measuring the orbits of their moons or of spacecraft flying past them. But an international group of astronomers have found a new way to weigh planets, and they have now weighed entire planetary systems using radio signals from pulsars. “This is first time anyone has weighed entire planetary systems — planets with their moons and rings,” said team leader Dr. David Champion of the Max-Planck-Institut fuer Radioastronomie in Bonn, Germany. “And we’ve provided an independent check on previous results, which is great for planetary science.”

Champion says measuring the masses of planets in this new way could feed into data needed for future space missions. Because mass creates gravity, and a planet’s gravitational pull determines the orbit of anything that goes around it — both the size of the orbit and how long it takes to complete – it will help more accurate navigation for future missions.

The new method is based on corrections astronomers make to signals from pulsars, small spinning stars that deliver regular ‘blips’ of radio waves.

The Earth is traveling around the Sun, and this movement affects exactly when pulsar signals arrive here. To remove this effect, astronomers calculate when the pulses would have arrived at the Solar System’s center of mass, or barycenter, around which all the planets orbit. Because the arrangement of the planets around the Sun changes all the time, the barycenter moves around too. To work out its position, astronomers use both a table (called an ephemeris) of where all the planets are at a given time, and the values for their masses that have already been measured. If these figures are slightly wrong, and the position of the barycenter is slightly wrong, then a regular, repeating pattern of timing errors appears in the pulsar data.

“For instance, if the mass of Jupiter and its moons is wrong, we see a pattern of timing errors that repeats over 12 years, the time Jupiter takes to orbit the Sun,” said Dr. Dick Manchester of CSIRO Astronomy and Space Science. But if the mass of Jupiter and its moons is corrected, the timing errors disappear. This is the feedback process that the astronomers have used to determine the planets’ masses.

Data from a set of four pulsars have been used to weigh Mercury, Venus, Mars, Jupiter and Saturn with their moons and rings. Most of these data were recorded with CSIRO’s Parkes radio telescope in eastern Australia, with some contributed by the Arecibo telescope in Puerto Rico and the Effelsberg telescope in Germany. The masses were consistent with those measured by spacecraft. The mass of the Jovian system, .0009547921(2) times the mass of the Sun, is significantly more accurate than the mass determined from the Pioneer and Voyager spacecraft, and consistent with, but less accurate than, the value from the Galileo spacecraft.

The new measurement technique is sensitive to a mass difference of two hundred thousand million million tons — just 0.003% of the mass of the Earth, and one ten-millionth of Jupiter’s mass.

“In the short term, spacecraft will continue to make the most accurate measurements for individual planets, but the pulsar technique will be the best for planets not being visited by spacecraft, and for measuring the combined masses of planets and their moons,” said CSIRO’s Dr. George Hobbs, another member of the research team.

Repeating the measurements would improve the values even more. If astronomers observed a set of 20 pulsars over seven years they’d weigh Jupiter more accurately than spacecraft have. Doing the same for
Saturn would take 13 years.

“Astronomers need this accurate timing because they’re using pulsars to hunt for gravitational waves predicted by Einstein’s general theory of relativity”, said Professor Michael Kramer, head of the ‘Fundamental Physics in Radio Astronomy’ research group at the Max-Planck-Institut fuer Radioastronomie. “Finding these waves depends on spotting minute changes in the timing of pulsar signals, and so all other sources of timing error must be accounted for, including the traces of Solar System planets.”

Astronomers from Australia, Germany, the UK, Canada and the USA are involved in this project.

Paper: Measuring the Mass of Solar System Planets Using Pulsar Timing

Source: Max Planck

Posted on by Nancy Atkinson

Our Solar System: Now 2 Million Years Older

Why Do Planets Orbit the Sun
The Solar System

Our solar system is beautiful and aging gracefully, but it might be even older than we originally thought, by as much as 2 million years. A group of scientists analyzed lead isotopes within a 1.49-kilo (3.2-pound) meteorite found in the Moroccan desert in 2004 and found evidence that suggests the mineral was formed 4.56 billion years ago, making the meteorite the oldest object ever found. This finding is between 300,000 and 1.9 million years older than previous estimates.

Marking the age of the Solar System has been defined as the time of formation of the first solid grains in the nebular disc surrounding the proto-Sun, and this has been done previously dating calcium–aluminium-rich inclusions in meteorites.

The team, led by Audrey Bouvier and Meenakshi Wadhwa of Arizona State University’s the Center for Meteorite Studies, looked at the extent to which uranium-238 and uranium-235 isotopes had decayed into their daughter isotopes lead-207 and lead-206.

Previous studies that dated the solar system looked at the Efremovka and Allende meteorites found in Kazakhstan in 1962 and Mexico in 1969, respectively.

While the timing may not seem like a big difference for something that is billions of years old, Bouvier said in New Scientist that it could make a difference when pinning down the conditions that led to the solar system’s formation, and those needed for other life-friendly planetary systems to form.

Their study was published by the journal Nature Geoscience.

Nature paper: Bouvier, A. & Wadhwa, M. Nature Geosci. advance online publication doi:10.1038/NGEO941 (2010).

Sources: New Scientist, PhysOrg

Posted on by Nancy Atkinson

Amazing Image: Map of Magnetic Field Lines of the Sun

Magnetic field lines on the Sun, on August 20, 2010. Credit: NASA SDO/Lockheed Martin Space Systems Compan

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The Sun’s corona is threaded with a complex network of magnetic fields, and this amazing new image from the Solar Dynamics Observatory shows the magnetic field lines associated with a coronal hole that is now turning to face Earth. This map is from data taken on August 20, 2010 by the Helioseismic and Magnetic Imager instrument (HMI). The magnetic field lines are color coded: white lines show fields that are closed, not releasing solar wind, and gold lines show open fields, letting solar wind escape. Understanding these magnetic fields is important because it is thought that solar storms and flares, which can affect us here on Earth, result from changes in the structure and connections of these fields.

Coronal holes are large regions in the corona that are darker, less dense and cooler than surrounding areas. The open structure of their magnetic field allows a constant flow of high-density plasma to stream out of the holes. There is an increase in the intensity of the solar wind effects on Earth when a coronal hole faces.

During a solar minimum, such as the one from which the Sun is just emerging, coronal holes are mainly found at the Sun’s polar regions, but they can be located anywhere on the sun during solar maximum. The fast-moving component of the solar wind is known to travel along open magnetic field lines that pass through coronal holes.

Scientists are finding out that much of the structure of the Sun’s corona is shaped by the magnetic field. Although it varies over time and from place to place on the Sun, the Sun’s magnetic field can be very strong. Inside sunspots, the magnetic field can be several thousand times the strength of the Earth’s magnetic field.

Learn more about magnetic field lines and how SDO’s HMI instrument will help us to better understand the Sun in this video from SDO:

More info: HMI webpage, SDO website

Sources: @Camilla_SDO Twitpic page, SDO Facebook, Solar Physics page from Montana University

Posted on by Nancy Atkinson

Danish Amateurs Hope To Launch Suborbital Rocket Next Week

Copenhagen Suborbital's HEAT rocket and Tycho Brahe capsule ready to launch. Credit: Copenhagen Suborbital

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It’s something like the movie “Astronaut Farmer,” but this is for real. And it’s in Danish. Copenhagen Suborbitals, headed by Kristian von Bengtson and Peter Madsen, hope to launch the world’s first amateur-built rocket for human space travel. As of this writing, the launch countdown clock on the Copenhagen Suborbitals’ website reads 7 days and 12 hours, which would put the launch on August 30 at about 1300 GMT. This upcoming flight will be an unmanned test flight, but if all goes well, Madsen hopes to be inside the single-passenger capsule named Tycho Brahe for a manned flight in the near future. They have a sea-launch site on the Baltic Sea near Bornholm, Denmark, and their HEAT 1-X rocket is ready to go.

Peter Madsen and Kristian von Bengtson. Credit: Copenhagen Suborbitals.

The team has been building their hybrid rocket since about 2004. Copenhagen Suborbitals is a non-profit endeavor, based entirely on sponsors and volunteers. Their mission: launch a human being into space. If they are successful, Denmark would become only the fourth nation to send a human into space. But this project is completely private – no national funds have been used. “We are working fulltime to develop a series of suborbital space vehicles – designed to pave the way for manned space flight on a micro size spacecraft,” said Madsen and von Bengtson on their website.

The Hybrid Exo Atmospheric Transporter or HEAT, is their booster rocket. It stands about 9 meters high, and it is a real scale rocket with a 640 mm diameter tube and uses liquid oxygen (LOX) for fuel. The HEAT booster will burn for about 60 seconds, providing 40kN of thrust, resulting in less than 3-g making the trip feasible for humans to endure in an upright position.

The flight trajectory for the HEAT rocket. Credit: Copenhagen Suborbitals.

The booster was successfully test-fired in February and May 2010. Copenhagen Suborbitals has also built three other rockets and successfully tested and flown them, including a small unmanned sounding rocket, named Hybrid Atmospheric Test Vehicle or HATV and smaller versions of the HEAT rocket.

“The mission has a 100% peaceful purpose and is not in any way involved in carrying explosive, nuclear, biological and chemical payloads,” said Madsen and von Bengtson.“We intend to share all our technical information as much as possible, within the laws of EU-export control.”

Previously, Madsen built the world’s largest home-made submarine, UC3 Nautilus. von Bengtson used to work for NASA. “This is the wildest thing I’ve made,” said Madsen in the Danish publication B.T. It is much wilder than the submarine.” Madsen added that he was tired of waiting for NASA, so decided to build a rocket himself.

The Tycho Brahe capsule is a single passenger capsule with a full view through a polymer plexiglas-dome so that the person can see and experience the entire ballistic ride. It has a pressurized volume providing support for one upright standing/half-sitting person. It will also have additional pressurized space, around and behind the astronaut, available for several other systems necessary for the flight procedure, and to support additional scientific and commercial project.

Peter Madsen inside the Tycho Brahe capsule. Credit: Copenhagen Suborbitals.

Copenhagen Suborbitals is taking donations, so check out their website. There’s also lots of images and videos available, on the site, too.

Since I am of one-half Danish heritage, I find this especially exciting. We’ll be following the progress of the Copenhagen Suborbitals’ historic flight. Stay tuned!

Posted on by Nancy Atkinson

Jupiter Gets Smacked Yet Again?

It looks like once again, Jupiter has taken a hit! And once again an amateur astronomer spotted and captured the event. Masayuki Tachikawa was observing Jupiter on at 18:22 Universal Time on August 20th (early on August 21 in Japan) and his video camera captured a 1-second-long flash on the planet’s disk, along the northern edge of the gas giant’s North Equatorial Belt. The event was reported by astronomer Junichi Watanabe from the National Astronomical Observatory of Japan, on his blog.
Continue reading “Jupiter Gets Smacked Yet Again?”

Posted on by Nancy Atkinson

‘Star Gazer’ Jack Horkheimer dies

The host of Public Television’s “Star Gazer” show, Jack Horkheimer, died on August 20, 2010. Originally called the ‘Star Hustler,’ the program ran for 30 years and Horkheimer’s craggy voice combined with his flamboyant, show-biz style made him a unique and internationally recognized pioneer in popularizing naked-eye astronomy. Horkheimer was 72 and died of a respiratory ailment, according to a spokesman for the Miami Museum of Science and Space Transit Planetarium, where Horkheimer was the executive director for over 35 years.
Continue reading “‘Star Gazer’ Jack Horkheimer dies”

Posted on by Tammy Plotner

Observing Spotlight – Dropping In On Jupiter…

Parallel/Cross-Eye 3D Image - Click For Full Size

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“Now that she’s back in the atmosphere, with drops of Jupiter in her hair…” Oh! Hey, there! Come on over and have a seat. Yeah, I really like that “Train” song, too. While the Moon is putting the brakes on deep sky observing, why don’t you take a look though the magnificent eye of the 9″ TMB refractor of Dietmar Hager and we world-wide friends can spend a little quality time together with Jupiter.

Here… You look through the eyepiece of a little telescope for awhile and I’ll tell you some of the things we know about this giant planet.

What’s that you say? Yes. Jupiter is big… Big enough to hold the mass of 1,000 Earths and about 1/10 the size of our Sun. Its a heavy-weight, too… But, believe it or not, Jupiter’s density is only about 1/4 of that of Earth’s. Scientists think this means the giant planet consists mostly of hydrogen and helium around a core of heavy elements. That means Jupiter more closely resembles a sun instead of a planet! Yeah… It’s hot there, too. As a matter of fact, Jupiter is putting out twice as much heat as it receives from Sol. Near the core temperature may be about 43,000 degrees F (24,000 degrees C)… Even hotter than the surface of the Sun. Hot enough to get a burn? Darn right. Those subtle tones of red and brown are chemical reactions much like what happens when we humans get a sunburn.

I see you smiling in the dark. Are you starting to notice details Jupiter’s cloud bands? Even a small telescope shows these areas called “zones”. This is where chemicals have formed colorful layers of clouds at different heights. The white belts are made of crystals of frozen ammonia and they are positioned much higher than the dark belts. Of course, you know all about the “Great Red Spot”, but sometimes it’s pretty hard to see unless you know when to look. Jupiter makes a complete rotation in about 10 hours, so even if you can’t see something right now – you can wait awhile and it will come around.

Speaking of coming around, did you notice how close one of Jupiter’s moon is getting to the edge of the planet? Then keep watching because we’re about to see a transit happen. Jupiter has at least 60 moons, but 4 of them are bright and very easy to see even in binoculars. They were discovered by Galileo, and that’s why you’ll sometimes hear them called the “galiean moons”. When they zip around behind Jupiter in their orbit, it’s called a occultation – but when they go in front of the planet from our point of view, it’s called a tranist. The really fun part is that you can not only see the little moon going across the surface, but a few minutes later? You can see the shadow, too! Here’s a little bit of magic from another friend of ours named Sander Klieverik.

Click to start animation...

Isn’t that just the coolest? You’re going to be hearing a lot about Sander’s work here in the near future. And there’s going to be a great Jupiter event he wants to make sure you know about!

“On October 31, 2010 Europa and Ganymede will simultaneously cross the cloud tops of Jupiter from 02:26 till 03:21 UT as do their shadows from 04:17 UT till 07:00 UT. Timing of entrance of the first moon, Ganymede will be around 00.20 UT, following by Europe at 02:26 UT. The first shadow will appear 04:09, quickly followed by Europe’s shadow at 04:16. Two shadows in very close proximity should be a very beautiful view! Circumstances are favourable as Jupiter has a visual diameter of around 48 arc seconds, being a month after opposition in which Jupiter reached almost 50 arc seconds (minimum 33″). For the non-astronomers, when a planet is in opposition it is roughly closest to the Earth at this point of its orbit, making it appear bigger and brighter. At that moment it is visible almost all night, rising around sunset, culminating around midnight and setting around sunrise.”

In the meantime, why don’t you keep practicing timing galiean events and seeing them? Here’s a handy Jupiter Moon Tool, and Sander has also prepared a Jupiter Almanac as well!

“But tell me, did the wind sweep you off your feet? Did you finally get the chance to dance along the light of day… And head back to the Milky Way? And tell me, did Venus blow your mind? Was it everything you wanted to find? And did you miss me 1hile you were looking for yourself out there?”

Now, quit bogarting that eyepiece… It’s my turn!

Many thanks to the one and only Dietmar Hager, Jupiter Video courtesy of Northern Galactic and the up and coming Sander Klieverik’s “AstronomyLive”. Song lyrics – “Drops of Jupiter” are from the artists “Train”. Let’s keep on rockin’ the night!