Evidence of forming planet discovered 335 light years from Earth

This graphic is an artist’s conception of the young massive star HD100546 and its surrounding disk. 

Credit: P. Marenfeld & NOAO/AURA/NSF

An international team of scientists led by a Clemson University astrophysicist has discovered new evidence that planets are forming around a star about 335 light years from Earth.

The team found carbon monoxide emission that strongly suggests a planet is orbiting a relatively young star known as HD100546. The candidate planet is the second that astronomers have discovered orbiting the star.

Theories of how planets form are well-developed. But if the new study's findings are confirmed, the activity around HD100546 would mark one of the first times astronomers have been able to directly observe planet formation happening.

New discoveries from the star could allow astronomers to test their theories and learn more about the formation of solar systems, including our own, said Sean Brittain, an associate professor of astronomy and astrophysics at Clemson.

"This system is very close to Earth relative to other disk systems," he said. "We're able to study it at a level of detail that you can't do with more distant stars. This is the first system where we've been able to do this.

"Once we really understand what's going on, the tools that we are developing can then be applied to a larger number of systems that are more distant and harder to see."

For more than a decade, the team has focused some of Earth's most powerful telescopes on a disk-shaped cloud of gas and dust that surrounds HD100546.

The star is about 2.5 times larger and 30 times brighter than the sun, Brittain said. It's in the constellation Musca, or The Fly, and can only be seen from the Southern Hemisphere.

Brittain made three trips to Chile as far back as 2003 to gather data for the research. He used telescopes at the Gemini Observatory and the European Southern Observatory.

The new planet astronomers believe they have found what would be an uninhabitable gas giant at least three times the size of Jupiter, Brittain said. Its distance from the star would be about the same distance that Saturn is from the sun.

The team used a technique called "spectro-astrometry," which enables small changes in the position of the carbon monoxide emission to be measured.

A source of excess carbon monoxide emission was detected that appears to vary in position and velocity. The varying position and velocity are consistent with orbital motion around the star.

More information: Astrophysical Journal paper - dx.doi.org/10.1088/0004-637X/791/2/136, Preprint on Arxiv: arxiv.org/abs/1409.0804

Astrophysical Journal Letters paper - iopscience.iop.org/2041-8205/766/1/L1/ , Preprint on Arxiv: arxiv.org/abs/1302.7122

NASA seeks Kuiper Belt Objects for New Horizon's post-Pluto mission

An artist’s conception of a KBO encounter by New Horizons. 

Credit: JHUAPL/SwRI.

Are you ready for the summer of 2015? A showdown of epic proportions is in the making, as NASA's New Horizons spacecraft is set to pass within 12,500 kilometres of Pluto, roughly a third of the distance of the ring of geosynchronous satellites orbiting the Earth, a little over a year from now on July 14th, 2015.

But another question is already being raised, one that's assuming center stage even before we explore Pluto and its retinue of moons: will New Horizons have another target available to study for its post-Pluto encounter out in the Kuiper Belt?

Researchers say time is of the essence to find it.

To be sure, it's a big solar system out there, and it's not that researchers haven't been looking.

New Horizons was launched from Cape Canaveral Air Force Station on January 19th, 2006 atop an Atlas V rocket flying in a 551 configuration in one of the fastest departures from Earth ever: it took New Horizons just nine hours to pass Earth's moon after launch.

The idea has always been out there to send New Horizons onward to explore and object beyond Pluto in the Kuiper Belt, but thus far, searches for a potential target have turned up naught.

A recent joint statement from NASA's Small Bodies and Outer Planets Assessment Groups (SBAG and OPAG) has emphasized the scientific priority needed for identifying a possible Kuiper Belt Object (KBO) for the New Horizons mission post-Pluto encounter.

The assessment notes that such a chance to check out a KBO up close may only come once in our lifetimes: even though it's currently moving at a heliocentric velocity of just under 15 kilometres a second, it will have taken New Horizons almost a decade to traverse the 32 A.U. distance to Pluto.

The report also highlights the fact that KBOs are expected to dynamically different from Pluto as well and worthy of study.

The statement also notes that the window may be closing to find such a favourable target after 2014, as the upcoming observational apparition of Pluto as seen from Earth, and the direction New Horizons is headed afterwards, reaches opposition this summer on July 4th.

But time is of the essence, as it will allow researchers to plan for a burn and trajectory change for New Horizons shortly after its encounter with Pluto and Charon using what little fuel it has left.

Then there's the issue of debris in the Pluto system that may require fine-tuning its trajectory pre-encounter as well.

New Horizons will begin long range operations later this year in November, switching on permanently for two years of operations pre-, during and post- encounter with Pluto.

New Horizons spends its last days on Earth pre-encapsulation. Credit: NASA/KSC

And there currently isn't a short-list of "next best thing" targets for New Horizons post-Pluto encounter.

One object, dubbed VNH0004, may be available for distant observations in January of next year, but even this object will only pass 75 million kilometres, about 0.5 A.U. from New Horizons at its closest.

Ground based assets such as the Keck, Subaru and Gemini observatories have been repeatedly employed in the search over the past three years.

The best hopes lie with the Hubble Space Telescope, which can go deeper and spy fainter targets.

Nor could New Horizons carry out a search for new targets on its own. Its eight inch (20 cm in diameter) LORRI instrument has a limiting magnitude of about +18, which is not even close to what would be required for such a discovery.

New Horizons currently has 130 metres/sec of hydrazine fuel available to send it onwards to a possible KBO encounter, limiting its range and maneuverability into a narrow cone straight ahead of the spacecraft.

This restricts the parameters for a potential encounter to 0.35 A.U. off of its nominal path for a target candidate be to still be viable objective.

New Horizons will exit the Kuiper Belt at around 55 A.U. from the Sun, and will probably end its days joining the Voyager missions probing the outer solar system environment.

Like Pioneers 10 and 11, Voyagers 1 and 2 and the upper stage boosters that deployed them, New Horizons will escape our solar system and orbit the Milky Way galaxy for millions of years.

We recently proposed a fun thought experiment concerning just how much extraterrestrial "space junk" might be out there, littering the galactic disk.

Kepler-186f: First potentially habitable Earth-sized planet confirmed - water

The artist's concept depicts Kepler-186f, the first validated Earth-size planet orbiting a distant star in the habitable zone, a range of distances from a star where liquid water might pool on the surface of an orbiting planet.

The discovery of Kepler-186f confirms that Earth-size planets exist in the habitable zone of other stars and signals a significant step closer to finding a world similar to Earth.

The artistic concept of Kepler-186f is the result of scientists and artists collaborating to help imagine the appearance of these distant worlds. 

Credit: Danielle Futselaar.

The first Earth-sized exoplanet orbiting within the habitable zone of another star has been confirmed by observations with both the W. M. Keck Observatory and the Gemini Observatory.

The initial discovery, made by NASA's Kepler Space Telescope, is one of a handful of smaller planets found by Kepler and verified using large ground-based telescopes.

It also confirms that Earth-sized planets do exist in the habitable zone of other stars.

"What makes this finding particularly compelling is that this Earth-sized planet, one of five orbiting this star, which is cooler than the Sun, resides in a temperate region where water could exist in liquid form," says Elisa Quintana of the SETI Institute and NASA Ames Research Center who led the paper published in the current issue of the journal Science.

The region in which this planet orbits its star is called the habitable zone, as it is thought that life would most likely form on planets with liquid water.

Steve Howell, Kepler's Project Scientist and a co-author on the paper, adds that neither Kepler (nor any telescope) is currently able to directly spot an exoplanet of this size and proximity to its host star.

"However, what we can do is eliminate essentially all other possibilities so that the validity of these planets is really the only viable option."

With such a small host star, the team employed a technique that eliminated the possibility that either a background star or a stellar companion could be mimicking what Kepler detected.

To do this, the team obtained extremely high spatial resolution observations from the eight-meter Gemini North telescope on Mauna Kea in Hawai`i using a technique called speckle imaging, as well as adaptive optics (AO) observations from the ten-meter Keck II telescope, Gemini's neighbour on Mauna Kea.

Together, these data allowed the team to rule out sources close enough to the star's line-of-sight to confound the Kepler evidence, and conclude that Kepler's detected signal has to be from a small planet transiting its host star.

The diagram compares the planets of the inner solar system to Kepler-186, a five-planet system about 500 light-years from Earth in the constellation Cygnus. 

The five planets of Kepler-186 orbit a star classified as a M1 dwarf, measuring half the size and mass of the sun. 

The Kepler-186 system is home to Kepler-186f, the first validated Earth-size planet orbiting a distant star in the habitable zone—a range of distances from a star where liquid water might pool on the surface of an orbiting planet. 

The discovery of Kepler-186f confirms that Earth-size planets exist in the habitable zone of other stars and signals a significant step closer to finding a world similar to Earth. 

Kepler-186f is less than ten percent larger than Earth in size, but its mass and composition are not known. 

Kepler-186f orbits its star once every 130-days and receives one-third the heat energy that Earth does from the sun, placing it near the outer edge of the habitable zone. 

The inner four companion planets all measure less than fifty percent the size of Earth. Kepler-186b, Kepler-186c, Kepler-186d, and Kepler-186e, orbit every three, seven, 13, and 22 days, respectively, making them very hot and inhospitable for life as we know it. 

The Kepler space telescope, which simultaneously and continuously measured the brightness of more than 150,000 stars, is NASA's first mission capable of detecting Earth-size planets around stars like our sun. 

Kepler does not directly image the planets it detects. The space telescope infers their existence by the amount of starlight blocked when the orbiting planet passes in front of a distant star from the vantage point of the observer. 

The artistic concept of Kepler-186f is the result of scientists and artists collaborating to help imagine the appearance of these distant Credit: Credit: NASA Ames/SETI Institute/JPL-CalTech.

More information: "An Earth-Sized Planet in the Habitable Zone of a Cool Star," by E.V. Quintana et al. Science, 2014.

Gemini Observatory: A new object at the edge of our Solar System

These are the discovery images of 2012 VP113, affectionately called 'Biden' because of the VP in the provisional name. 

It has the most distant orbit known in our Solar System. 

Three images of the night sky, each taken about two hours apart, were combined into one.

The first image was artificially colored red, second green and third blue. 

2012 VP113 moved between each image as seen by the red, green and blue dots. 

The background stars and galaxies did not move and thus their red, green and blue images combine to showup as white sources. 

Credit: Scott Sheppard and Chad Trujillo

The Solar System has a new most-distant member, bringing its outer frontier into focus.

New work from Scott Sheppard of Carnegie and Chadwick Trujillo of the Gemini Observatory reports the discovery of a distant dwarf planet, called 2012 VP113, which was found beyond the known edge of the Solar System.

This is likely one of thousands of distant objects that are thought to form the so-called inner Oort cloud.

What's more, their work indicates the potential presence of an enormous planet, perhaps up to 10 times the size of Earth, not yet seen, but possibly influencing the orbit of 2012 VP113, as well as other inner Oort cloud objects.

Their findings are published March 27 in Nature.

The paper is Sheppard and Trujillo, “A Sedna-like body with a perihelion of 80 astronomical units,” Nature 507 (27 March, 2014), 471-474.

The known Solar System can be divided into three parts: the rocky planets like Earth, which are close to the Sun; the gas giant planets, which are further out; and the frozen objects of the Kuiper belt, which lie just beyond Neptune's orbit.

Beyond this, there appears to be an edge to the Solar System where only one object, Sedna, was previously known to exist for its entire orbit.

But the newly found 2012 VP113 has an orbit that stays even beyond Sedna, making it the furthest known in the Solar System.

"This is an extraordinary result that redefines our understanding of our Solar System," says Linda Elkins-Tanton, director of Carnegie's Department of Terrestrial Magnetism.

These images show the discovery of the new inner Oort cloud object 2012 VP113 taken about 2 hours apart on UT November 5, 2012. 

The motion of 2012 VP113 clearly stands out compared to the steady state background stars and galaxies. 

Credit: Scott S. Sheppard: Carnegie Institution for Science

Sedna was discovered beyond the Kuiper Belt edge in 2003, and it was not known if Sedna was unique, as Pluto once was thought to be before the Kuiper Belt was discovered.

With the discovery of 2012 VP113 it is now clear Sedna is not unique and is likely the second known member of the hypothesized inner Oort cloud, the likely origin of some comets.

2012 VP113's closest orbit point to the Sun brings it to about 80 times the distance of the Earth from the Sun, a measurement referred to as an astronomical unit or AU.

For context, the rocky planets and asteroids exist at distances ranging between .39 and 4.2 AU.

Gas giants are found between 5 and 30 AU, and the Kuiper belt (composed of thousands of icy objects, including Pluto) ranges from 30 to 50 AU.

In our solar system there is a distinct edge at 50 AU. Only Sedna was known to stay significantly beyond this outer boundary at 76 AU for its entire orbit.

More information: Paper: dx.doi.org/10.1038/nature13156

Chandra Image of NGC 6946: The 'Fireworks Galaxy'

NGC 6946 is a medium-sized, face-on spiral galaxy about 22 million light years away from Earth. 

In the past century, eight supernovas have been observed to explode in the arms of this galaxy.

Chandra observations (purple) have, in fact, revealed three of the oldest supernovas ever detected in X-rays, giving more credence to its nickname of the "Fireworks Galaxy." 

This composite image also includes optical data from the Gemini Observatory in red, yellow, and cyan. 

Image credit: X-ray: NASA/CXC/MSSL/R.Soria et al, Optical: AURA/Gemini OBs

Gemini's infrared instrument Flamingos-2: Poised for discovery

This FLAMINGOS-2 image details part of the magnificent Swan Nebula (M17), where ultraviolet radiation streaming from young hot stars sculpts a dense region of dust and gas into myriad fanciful forms. 

M17 lies some 5,200 light-years distant in the constellation Sagittarius and is one of the most massive and luminous star-forming region's in our Galaxy. 

It is also one of the most studied. Field of view: 5.5 x 4.0 arcmin. 

Credit: Gemini Observatory/AURA

Gemini Observatory's latest instrument, a powerful infrared camera and spectrograph at Gemini South, reveals its potential in a series of striking on-sky commissioning images released today.

Gemini Observatory's latest tool for astronomers, a second-generation infrared instrument called FLAMINGOS-2, has "traveled a long road" to begin science observations for the Gemini scientific community.

Recent images taken by FLAMINGOS-2 during its last commissioning phase dramatically illustrate that the instrument was worth the wait for astronomers around the world who are anxious to begin using it.

Nancy Levenson

"It's already one of our most requested instruments at the Gemini telescopes," remarks Nancy Levenson, Gemini's Deputy Director and Head of Science.

"We see a long and productive life ahead for FLAMINGOS-2 once astronomers really start using it later this year."

"It has not been an easy journey," says Percy Gomez Gemini's FLAMINGOS-2 Instrument Scientist, "but thanks to the dedicated work of Gemini engineers and scientists very soon astronomers will be able to use a reliable and robust instrument."

After significant redesign and rebuilds for optimal performance on the Gemini South telescope, FLAMINGOS-2 has proven that it will provide astronomers with a powerful mix of capabilities.

These include extreme sensitivity to infrared (heat) radiation from the universe, high-resolution wide-field imaging, and a combination of spectroscopic capabilities that will allow cutting-edge research in topics spanning from the exploration of our Solar System, to the most distant and energetic explosions in our universe.

GRB Explosion illuminates invisible galaxy in the dark ages

Before light from the gamma-ray burst arrives at the Earth for astronomers to study, it passes through interstellar gas in its host galaxy (close-up view, left), and intergalactic gas between the distant galaxy and us (wide view, right).

This gas filters the light by absorbing some colors and leaves a signature on the light that can be seen in its spectrum.

This "signature" allows scientists to characterize the gamma-ray burst, its environment, and the material between us and the distant galaxy.

Credit: Gemini Observatory/AURA, artwork by Lynette Cook

More than 12 billion years ago a star exploded, ripping itself apart and blasting its remains outward in twin jets at nearly the speed of light. At its death it glowed so brightly that it outshone its entire galaxy by a million times.

This brilliant flash traveled across space for 12.7 billion years to a planet that hadn't even existed at the time of the explosion - our Earth.

By analyzing this light, astronomers learned about a galaxy that was otherwise too small, faint and far away for even the Hubble Space Telescope to see.

Ryan Chornock

"This star lived at a very interesting time, the so-called dark ages just a billion years after the Big Bang," says lead author Ryan Chornock of the Harvard-Smithsonian Center for Astrophysics (CfA).

"In a sense, we're forensic scientists investigating the death of a star and the life of a galaxy in the earliest phases of cosmic time," he adds.

The star announced its death with a flash of gamma rays, an event known as a gamma-ray burst (GRB).

GRB 130606A was classified as a long GRB since the burst lasted for more than four minutes.

It was detected by NASA's Swift spacecraft on June 6th. Chornock and his team quickly organized follow-up observations by the MMT Telescope in Arizona and the Gemini North telescope in Hawaii.

"We were able to get right on target in a matter of hours," Chornock says. "That speed was crucial in detecting and studying the afterglow."

A GRB afterglow occurs when jets from the burst slam into surrounding gas, sweeping that material up like a snowplow, heating it, and causing it to glow.

As the afterglow's light travels through the dead star's host galaxy, it passes through clouds of interstellar gas.

Chemical elements within those clouds absorb light at certain wavelengths, leaving "fingerprints." By splitting the light into a rainbow spectrum, astronomers can study those fingerprints and learn what gases the distant galaxy contained.

All chemical elements heavier than hydrogen, helium, and lithium had to be created by stars.

As a result those heavy elements, which astronomers collectively call "metals," took time to accumulate. Life could not have existed in the early universe because the elements of life, including carbon and oxygen, did not exist.

Chornock and his colleagues found that the GRB galaxy contained only about one-tenth of the metals in our solar system. Theory suggests that although rocky planets might have been able to form, life probably could not thrive yet.

"At the time this star died, the universe was still getting ready for life. It didn't have life yet, but was building the required elements," says Chornock.

At a redshift of 5.9, or a distance of 12.7 billion light-years, GRB 130606A is one of the most distant gamma-ray bursts ever found.

"In the future we will be able to find and exploit even more distant GRBs with the planned Giant Magellan Telescope," says Edo Berger of the CfA, a co-author on the publication.