"The foundation has been laid and now the building materials are coming together to make a new solar system."
Located about 180 light-years away in the constellation Hydra the Water Snake, TW Hydrae consists of a 10 million-year-old
star about four-fifths as massive as the Sun. The protoplanetary disk surrounding TW Hydrae contains about one-tenth
as much material as the Sun -- more than enough to form many Jupiter-sized worlds.
Artist's Conception of Dusty Disk Around Young Star TW Hydrae. Credit: Bill Saxton, NRAO/AUI/NSF
"TW Hydrae is unique," said Wilner. "It's nearby, and it's just the right age to be forming planets. We'll be studying
it for decades to come."
Now, another group of astronomers carefully observe this amazing, massive TW Hydrae, using the European Space
Agency's Herschel Space Telescope, a mission in which NASA is a participant,
A star thought to have passed the age at which it can form planets may, in fact, be creating new worlds.
The disk of material surrounding the surprising star called TW Hydrae may be massive enough to make even more
planets than we have in our own solar system.
"We didn't expect to see so much gas around this star," said Edwin Bergin of the University of Michigan in Ann Arbor.
Bergin led the new study appearing in the journal Nature.
"Typically stars of this age have cleared out their surrounding material, but this star still has enough mass to make
the equivalent of 50 Jupiters," Bergin said.
In addition to revealing the peculiar state of the star, the findings also demonstrate a new, more precise method
for weighing planet-forming disks. Previous techniques for assessing the mass were indirect and uncertain.
The new method can directly probe the gas that typically goes into making planets.
Planets are born out of material swirling around young stars, and the mass of this material is a key factor controlling
their formation. Astronomers did not know before the new study whether the disk around TW Hydrae contained enough material
to form new planets similar to our own.
Click on image to enlarge
Misty Star in the Sea Serpent
This artist's concept illustrates an icy planet-forming disk around a young star called TW Hydrae, located about 175 light-years away in the Hydra, or Sea Serpent, constellation. Astronomers using the Herschel Space Observatory detected copious amounts of cool water vapor, illustrated in blue, emanating from the star's planet-forming disk of dust and gas. The water vapor, which probably comes from icy grains in the disk, is located in the frigid outer regions of the star system, where comets will take shape.
In our own solar system, comets are thought to have carried water to Earth, creating our oceans. A similar process might be taking place around TW Hydrae -- comets could, over the next several millions of years, transport water to young worlds. The Herschel results demonstrate that vast reservoirs of water are available around stars for creating these hypothetical water worlds.
Herschel is a European Space Agency mission with significant NASA contributions. Launched in 2009, the spacecraft carries science instruments provided by consortia of European institutes. NASA's Herschel Project Office based at JPL contributed mission-enabling technology for two of Herschel's three science instruments. The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena, supports the U.S. astronomical community. Caltech manages JPL for NASA.
Image credit: NASA/JPL-Caltech
"Before, we had to use a proxy to guess the gas quantity in the planet-forming disks," said Paul Goldsmith, the NASA
project scientist for Herschel at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
"This is another example of Herschel's versatility and sensitivity yielding important new results about star and planet formation."
Using Herschel, scientists were able to take a fresh look at the disk with the space telescope to analyze
light coming from TW Hydrae and pick out the spectral signature of a gas called hydrogen deuteride, which is
a heavier version of hydrogen, emitting light at longer, far-infrared wavelengths that Herschel is equipped to see.
Astronomers measured the levels of hydrogen deuteride and obtain the weight of the disk with the highest precision yet.
"Knowing the mass of a planet-forming disk is crucial to understanding how and when planets take shape around other stars,"
said Glenn Wahlgren, Herschel program scientist at NASA Headquarters in Washington.
Whether TW Hydrae's large disk will lead to an exotic planetary system with larger and more numerous planets than
ours remains to be seen, but the new information helps define the range of possible planet scenarios.
"The new results are another important step in understanding the diversity of planetary systems in our universe,"
said Bergin. "We are now observing systems with massive Jupiters, super-Earths, and many Neptune-like worlds.
By weighing systems at their birth, we gain insight into how our own solar system formed with just one of many
possible planetary configurations."
The Wandering Stars
In ancient civilizations, people pondered the meanings of the stars, watching for clues to their survival: the beginning of planting and
harvesting times, the seasons, and even portents of danger.
They soon noticed that certain stars didn't stay in place, but wandered amongst the fixed star field.
"The Most Profound Mystery In All Of Science" -
Little is known about this force and its its repulsive gravity, which is causing the expansion of the universe to accelerate.
The riddles of dark matter and cosmic inflation, along with dark energy, these are the three pillars of modern cosmological theory,"
and none of them can be explained with physics that we know," Michael Turner, director of the Kavli Institute for Cosmological Physics says.
Doesn't Secret Dark Matter Exist?
The more scientists study dark matter they know lesser and are not particularly optimistic about their results.
After completing this study, we know less about dark matter than we did before," said Matt Walker, of the Harvard-Smithsonian Center for Astrophysics.
A mysterious and still unknown substance is totally invisible in the Universe and reveals its presence only through its gravitational pull.
Mysteries Of A Dark Universe
Cosmology, the study of the universe as a whole, has been turned on its head by a stunning discovery that the universe is flying apart in all directions at an ever-increasing rate. Is the universe really as we think it should be? Or is nature somehow fooling us?
The astronomers whose data revealed this accelerating universe have been awarded the Nobel Prize for Physics.
Black Holes With No 'Table Manners' Eat Two Courses At Once!
It is still unknown how the supermassive black holes (SMBH) in galaxy centres accrete gas and grow.
Researchers from the University of Leicester (UK) and Monash University in Australia have investigated how some black holes got so big so fast that they are billions of times heavier than the sun.
Mercury Surprises Scientists
On March 17, MESSENGER (MErcury Surface, Space Environment, GEochemistry, and Ranging) completed its one-year primary mission, orbiting Mercury, capturing nearly 100,000 images, and recording data
that reveals new information about the planet's core, topography, and the mysterious radar bright material in the permanently shadowed areas near the poles.
Living Earth Simulator - Supercomputer Predicting The Future
In Douglas Adams book the Hitchhikers Guide to the Galaxy we encounter a machine called Deep Thought. It is the most powerful computer ever built. Deep Thought is capable of answering questions
concerning life, the Universe, and simply everything. Now scientists are planning to create a similar machine. It is called the Living Earth Simulator (LES).
Warp-Speed Planets Are Some Of The Fastest Objects In The Milky Way
Warped planets are some of the fastest objects in the Milky Way and they zoom through space near the speed of light.
Some years ago astronomers were astonished when they they found the first runaway star flying out of our Galaxy at a speed of 1.5 million miles per hour.
The discovery intrigued theorists, who wondered: If a star can get tossed outward at such an extreme velocity, could the same thing happen to planets?
Though the universe is filled with billions upon billions of stars, the discovery of a single variable star in 1923 altered the
course of modern astronomy. And, at least one famous astronomer of the time lamented that the discovery had shattered his world view.
Kepler Will Find Goldilocks Planet Within The Next Two Years
NASA's Kepler spacecraft is discovering a veritable avalanche of alien worlds. Recent finds include planets with double suns, massive
"super-Earths" and "hot Jupiters," and a miniature solar system.
The variety of planets circling distant suns is as wonderful as it is surprising.