For the giant planet atmospheres (Jupiter, Saturn), there is an artificial lower boundary, at which drag acts and from which an intrinsic heat flux can emanate.
The timescale
for giant planet formation: constraints from the rotational evolution of exoplanet host stars
«Jupiter is the oldest planet of the solar system, and its solid core formed well before the solar nebula gas dissipated, consistent with the core accretion model
for giant planet formation.»
«Hunting
for giant planet analogs in our own backyard.»
If certain debris disks are able to hold onto appreciable amounts of gas, it might push back astronomers» expected deadline
for giant planet formation around young stars, the astronomers speculate.
This finding could offer new insights into the timeline
for giant planet formation around young stars.
We find that the global false positive rate of Kepler is 9.4 %, peaking
for giant planets (6 - 22 Earth radii) at 17.7 %, reaching a low of 6.7 % for small Neptunes (2 - 4 Earth radii), and increasing again for Earth - size planets (0.8 - 1.25 Earth radii) to 12.3 %.
An Extreme - AO Search
for Giant Planets around a White Dwarf — VLT / SPHERE performance on a faint target GD 50
Mounted on the 8 - meter Gemini South Telescope in Chile, the Imager began searching
for giant planets circling 600 young stars in November 2014.
We performed a pilot study with the extreme - AO system on the Spectro - Polarimetric High - contrast Exoplanet REsearch (SPHERE) on the Very Large Telescopes (VLT) to look
for giant planets around a young white dwarf, GD 50.
Not exact matches
If the
planet is to avert the worst scenarios
for climate change, the optimistic long - run forecasts
for oil demand growth put forward by energy
giants such as Exxon can be thrown out the window.
As
for me, I can't believe in an human - like being that designed and jump - started the universe 13.8 billion years ago and set aside a
planet for His special favorite creations, so He'd have someone to keep Him company and sing songs praising Him, then gave Bronze Age hermits a book of His orders to mankind that includes «thou shalt not round thy head nor cut thy beard» on penalty of eternal suffering... just CA N'T, any more than I can force myself to believe the world rests on the back of
giant turtle.
We need to take care of our
planet and each other the chances of a random meteor or
giant solar flare exists still they have nothing to do with a mythology created
for those who choose to be unaccountable
for their part in our future.
The
planet is not a
giant trash can, and we feel like the least we can do is think about the things we're responsible
for leaving behind, and make sure they're really needed, valued and used to the fullest.
While the Cassini spacecraft is gone, its enormous collection of data about Saturn — the
giant planet, its magnetosphere, rings and moons — will continue to yield new discoveries
for decades to come.
Astronomers this month announced a similar discovery
for an even larger gas
giant, reporting that the Juno spacecraft, which is orbiting Jupiter, had found that the
planet's rotating cloud belts reach roughly 3,000 kilometers below the top of the atmosphere.
While such circumplanetary disks have been theorized to surround
giant planets at birth and to control the flow of gas onto the growing
planet, these findings are the first observational evidence
for their existence.
While they are theoretically predicted to surround
giant planets at birth, there has been little observational evidence to date
for circumplanetary disks outside the solar system.
«
For instance, the «brown dwarf desert,» an unexplained paucity of objects that are larger than
giant planets but smaller than stars.
The aerospace
giant's «Mars Base Camp» plan could send crews to the Red
Planet's surface
for multi-year stays
«Ultimately, we found that Jupiter is capable of ejecting the fifth
giant planet while retaining a moon with the orbit of Callisto,» said Cloutier, who is also a graduate fellow at the Centre
for Planetary Sciences at the University of Toronto at Scarborough.
For years, astronomers expected to see elsewhere what they saw in our own orderly solar system: rocky
planets close to a star and gas
giants farther away, all in neat, nearly circular orbits.
But according to Takeshi Oka of the University of Chicago, «if the findings are confirmed, Brittain and Rettig have discovered a new astronomical object, opening up a new avenue
for the study of the formation of
giant planets.»
They monitored more than 34,000 stars, searching
for slight dips in their brightnesses from the shadows of
giant planets crossing in front.
After a decade of searching
for planets orbiting stars like our sun, astronomers had found nothing but
giant planets, most of them gas balls like Jupiter, around other stars.
«If it messes up Jupiter, we don't have a complete model
for the evolution of the
giant planets.»
Far from the sun's heat, temperatures were cold enough
for water to freeze and provide lots of the solid particles from which
giant planets could grow.
Giant planets are mostly made of gas and ice, and there are two prevailing hypotheses
for how all this material came together as a
planet.
The moon's host
planet, a gas
giant about the size of Uranus, hangs huge in the sky as always, its churning storms a constant sight
for the inhabitants below.
MESSENGER — which stands
for Mercury surface, space environment, geochemistry, and ranging — also determined that Mercury's
giant Caloris basin, among the biggest impact craters in the solar system, spans 1,500 kilometers — nearly one third of the
planet's diameter and 200 kilometers more than previous estimates.
Humanity has just gained its best - ever views of Jupiter's Great Red Spot, a storm large enough to swallow Earth whole that has raged
for centuries in the gas -
giant planet's atmosphere.
Big trees and blue whales are easily spotted when searching
for the Earth's biggest living things — but not all of our
planet's
giants are so obvious.
Next week is make or break time
for Galileo as the spacecraft prepares to send a probe down to the
giant planet
The
giant - impact theory can account
for the high angular momentum of the Earth - moon system, which is greater than that of any known
planet - satellite system.
«If you polled my community about what we'd wish
for our ideal observatory, it wouldn't be Webb — it would be something else,» says Sasha Hinkley, an astronomer at the University of Exeter in England leading an ERS program to directly image
giant planets.
The combined gravity of the second and third stars would have kept the gas and dust disk of the primary star at a maximum radius of 200 million kilometers — too close
for the formation of
giant planets.
However, another planetary building block does appear to linger: the gaseous parts of the disks, perhaps fostering additional growth of gas -
giant planets like Jupiter
for millions of years.
Some scientists suggest that
giant radiation flares could deplete the ozone layer of a
planet by 94 %
for two years and could even be fatal
for all life.
Polar cyclones on Saturn are a puzzling phenomenon, since the
planet, known as a gas
giant, lacks an essential ingredient
for brewing up such storms: water on its surface.
But when NASA's MESSENGER spacecraft detected lots of sulfur and potassium in the crust of Mercury earlier this year, many planetary scientists believed this ruled out the
giant - impact scenario
for the innermost
planet.
But there is a third type of
planet in our solar system — part gas, part ice — and this is the first time anyone has spotted a twin
for our so - called «ice
giant»
planets, Uranus and Neptune.
Lawrence Livermore scientists
for the first time have experimentally re-created the conditions that exist deep inside
giant planets, such as Jupiter, Uranus and many of the
planets recently discovered outside our solar system.
«In 2007, we began our long - term search
for gas
giant planets and brown dwarfs orbiting nearby low mass dwarf stars,» said Boss.
In an experiment designed to mimic the conditions deep inside the icy
giant planets of our solar system, scientists were able to observe «diamond rain»
for the first time as it formed in high - pressure conditions.
Piecing those clues together, the two Alvarezes proposed a radical idea: The mass extinction that wiped out the dinosaurs 65 million years ago was caused by the impact of a
giant asteroid, which unleashed a globe - spanning cloud of debris and plunged the
planet into darkness
for months.
With their gas depleted, it may be impossible
for the disks around stars in massive clusters to form
giant planets like Jupiter or Saturn.
The extension would last
for 7 years, allowing the probe to watch Saturn and its moons as summer comes to the
giant planet's northern hemisphere
for the first time in 30 years.
At first blush, another potential problem comes from NASA's Widefield Infrared Survey Explorer (WISE), a satellite that completed an all - sky survey looking
for the heat of brown dwarfs — or
giant planets.
In 1846,
for example, the French mathematician Urbain Le Verrier predicted the existence of a
giant planet from irregularities in the orbit of Uranus.
Tentatively slated
for a 2022 launch, the probe will orbit Jupiter and make about 45 passes by the
giant planet's moon Europa, which has a global ocean just beneath its ice - covered surface.