When you want to see the stars, find someplace dark
Today the planet Uranus will pass through opposition, directly opposite the Sun in our sky. The planet will be well placed for observation all night long, rising at sunset, transiting at midnight, and setting at sunrise. If you are looking to observe Uranus, it is currently shining at magnitude 5.7 in the center of the constellation Pisces.
W. M. Keck Observatory press release…
The normally bland face of Uranus has become increasingly stormy, with enormous cloud systems so bright that for the first time ever, amateur astronomers are able to see details in the planet’s hazy blue-green atmosphere.
“The weather on Uranus is incredibly active,” said Imke de Pater, professor and chair of astronomy at the University of California, Berkeley, and leader of the team that first noticed the activity when observing the planet with adaptive optics on the W. M. Keck Observatory in Hawaii.
In all, de Pater, Hammel and their team detected eight large storms on Uranus’s northern hemisphere when observing the planet with the Keck Observatory on August 5 and 6. One was the brightest storm ever seen on Uranus at 2.2 microns, a wavelength that senses clouds just below the tropopause, where the pressure ranges from about 300 to 500 mbar, or half the pressure at Earth’s surface. The storm accounted for 30 percent of all light reflected by the rest of the planet at this wavelength.
When amateur astronomers heard about the activity, they turned their telescopes on the planet and were amazed to see a bright blotch on the surface of a normally boring blue dot.
French amateur astronomer Marc Delcroix processed the amateur images and confirmed the discovery of a bright spot on an image by French amateur Régis De-Bénedictis, then in others taken by fellow amateurs in September and October. He had his own chance on Oct. 3 and 4 to photograph it with the Pic du Midi one-meter telescope, where on the second night, “I caught the feature when it was transiting, and I thought, ‘Yes, I got it!’” said Delcroix.
Continue reading “Astronomers Thrilled by Extreme Storms on Uranus”
W. M. Keck Observatory press release…
Weather on any planet can be quite unpredictable. As hurricanes threaten the Aloha State, astronomers working at W. M. Keck Observatory on the island of Hawaii were surprised by the appearance of gigantic swirling storm systems on the distant planet Uranus.
In the past few days, however, astronomers were surprised by a multitude of bright storms on the planet, including one monstrous feature.
“We are always anxious to see that first image of the night of any planet or satellite, as we never know what it might have in store for us,” said Imke de Pater, professor at UC Berkeley and team leader. “This extremely bright feature we saw on UT 6 August 2014 reminds me of a similarly bright storm we saw on Uranus’s southern hemisphere during the years leading up to and at equinox”.
Over the next few days Venus will swing quite close to Uranus. Today the pair is separated by 2°48′. This will decrease to 1°15′ on the 15th for the closest approach.
Much like the Venus and Neptune pair we saw last month, the pair is quite a mismatch… Uranus is a mere 5.1 magnitude while Venus is a brilliant -4.0. There will be two 4th magnitude stars to the north of the pair, δPsc and εPsc, but these will be about 4° away from Venus and should be easy to distinguish. Look for Neptune betwixt Venus and the stars.
The planet Uranus, known since Voyager’s 1986 flyby as a bland, featureless blue-green orb, is beginning to show its face.
By using a new technique with the telescopes of the Keck Observatory, astronomers have created the most richly detailed, highest-resolution images ever taken of the giant ice planet in the near infrared, revealing an incredible array of atmospheric detail and more complex weather.
The planet, in fact, looks like many of the solar system’s other large planets — the gas giants Jupiter and Saturn, and the ice giant Neptune — said Imke de Pater, professor and chair of astronomy at the University of California, Berkeley, and one of the team members. The planet has bands of circulating clouds, massive swirling hurricanes and an unusual swarm of convective features at its north pole.
“This ‘popcorn’ appearance of Uranus’s pole reminds me very much of a Cassini image of Saturn’s south pole,” said de Pater.
Saturn’s south pole is characterized by a polar vortex or hurricane, surrounded by numerous small cloud features that are indicative of strong convection and analogous to the heavily precipitating clouds encircling the eye of terrestrial hurricanes. De Pater’s group suggested that a similar phenomenon would be present on Neptune, based upon Keck observations of that planet.
“Perhaps we will also see a vortex at Uranus’ pole when the pole comes in full view,” she said.
The study was led by Larry Sromovsky, a planetary scientist at the University of Wisconsin, Madison. In addition to de Pater, other team members are Pat Fry of the University of Wisconsin and Heidi Hammel of the Association of Universities for Research in Astronomy. The team will report the details of their observations Oct. 17 at a meeting of the American Astronomical Society’s Division of Planetary Sciences in Reno, Nev.
Continue reading “Keck Observations Reveal Complex Face of Uranus”
Mercury and Uranus will meet up in the dawn over the next few days. The pair is separated by about 3° this morning. Tomorrow morning the separation will have diminished to about 2°19′. Close approach will be on the morning of April 22nd at almost exactly 2°. On the 23rd the separation will have increased to 2°14′. Both planets will be well up, about 17° elevation at sunrise.
While Mercury is easy to pick out with the unaided eye. Uranus will require at least a pair of binoculars to see at 5.9 magnitude. The close approach will aid in finding the outer planet. Check your charts, there are a couple 6th magnitude stars just as close to Mercury to confuse for the dimmer planet.