Now at Ceres, Dawn’s camera recorded this closer view of the dwarf planet’s northern hemisphere and one of its mysterious bright spots on May 4. A sunlit portrait of a small, dark world about 950 kilometers in diameter, the image is part of a planned sequence taken from the solar-powered spacecraft’s 15-day long RC3 mapping orbit at a distance of 13,600 kilometers (8,400 miles). This animated sequence shows Ceres’ rotation, its north pole at the top of the frame. Imaged by Hubble in 2004 and then by Dawn as it approached Ceres in 2015, the bright spot itself is revealed to be made up of smaller spots of reflective material that could be exposed ice glinting in the sunlight. On Saturday, Dawn’s ion propulsion system was turned on to spiral the spacecraft into a closer 4,350-kilometer orbit by June 6. Of course another unexplored dwarf planet, Pluto, is expecting the arrival of a visitor from Earth, the New Horizons spacecraft, by mid-July.
Dwarf Planet Ceres and its Mysterious Bright Spot
Image Credit: NASA, JPL-Caltech, UCLA, MPS/DLR/IDA
#TBT Click anywhere on the article to view it in full size.
If you enjoy observing comets, there are a couple of great opportunities right now to check out these icy travelers!
Comet C/2014 E2 (Jacques) is visible in evening skies again. This comet originated in the Oort cloud and was discovered on March 13, 2014 by Cristavao Jacques and the Southern Observatory for Near Earth Asteroids Research, a.k.a. SONEAR. This comet hung out in the evening sky for most of the Spring, brightening ever so slowly and finally reaching perihelion on July 2, 2014. Thanks to our nearest star, the comet has developed a tail and finally “looks” like a comet. Currently, this comet can be found in Cassiopeia and is visible through 10×50 binoculars as a faint fuzzball in a field of stars. Larger scopes will reveal the comet’s tail structure, and even larger scopes will show a faint green color, representing cyanogen and carbon emissions. C/2014 E2 (Jacques) is holding at magnitude 7 for now and is expected to brighten only slightly through September. This puts it out of the range of naked eye visibility, but makes it a great target for binoculars, telescopes, and imagers with even modest equipment.
C/2014 E2 (Jacques) by Michael Jager
C/2014 E2 (Jacques) Stellarium.org
Comet C/2013 V5 (Oukaimeden) is not quite as bright as it’s evening companion and you’ll have to get up early (or stay up late) to see it in the constellation Monoceros. It’s currently at around magnitude 9, but is expected to brighten to around magnitude 5 by mid-September, putting it on the threshold of naked eye visibility from dark sky sites, such as Jon Wood Astronomy Field. This comet was discovered last November by astronomers at the Oukaimeden Observatory in Marrakech, Morocco. C/2013 V5 (Oikaimeden) originates from the Oort cloud as well and is expected to make a trip through our solar system once every 6,000 years. You’ll find this comet low in the eastern sky about 2 hours before sunrise in the constellation Monoceros. If you’re in the northern hemisphere, you’ll be able to see the comet until the start of September. Observers and imagers in the southern hemisphere will be able to track it for quite some time.
C/2013 V5 (Oukaimeden) Damian Peach
C/2013 V5 (Oukaimeden) Stellarium.org
#OTD in 1877 American astronomer Asaph Hall discovers Phobos, innermost moon orbiting Mars. It took the U.S. Naval Observatory’s giant 26-inch telescope to located tiny Phobos, whose mean radius is less than 7 miles.
Interestingly, Phobos is slowly spiraling closer to Mars, and will impact the plant in less than 100 million years.
Courtesy of NASA
Make your evening plans… head outside tonight about an hour after sunset and look southwest for two bright objects: ruddy Mars and brilliant blue-white Spica. The pair will be close, really close… less than 2 degrees apart! Saturn too, is lurking, about 12 degrees away at 10 o’clock from the Mars-Spica pairing. Enjoy.
#OTD in 2000, the Russian Zvezda Service Module was launched from the Baikonur Cosmodrome in Kazakhstan, en route to the #ISS. The 40-plus foot module currently provides much-needed living quarters, life support, communications, and a docking station.
In related news, #Today is the 5,000th day humans have been aboard #ISS.
#OTD… July 9, 1979, Voyager 2 officially passes Jupiter on its way to visit the other three gas giants – Saturn (1981), Uranus (1986), and Neptune (1989).
Launched August 20,1977, Voyager 2 has been travelling for more than 36 years and is nearly 12 billion miles from Earth. If we could suddenly travel at the speed of light, we could catch Voyager 2 in just over 14.5 minutes!
The First Quarter Moon, ruddy Mars, and brilliant blue-white Spica form a tight trio in the early nighttime sky. Northern hemisphere observers will see the halfway lit Moon and Mars less than 1 degree apart. Those observers in Central and South America will witness the moon pass directly in front of (occult) Mars!
Go outside just after dark and find the moon… easy. Mars will be just to the right and Spica off to the left. Enjoy.
#OTD in 1997, NASA’s Pathfinder probe, carrying the Carl Sagan Memorial Station and Sojourner rover, lands in the Ares Vallis region of Mars. The landing was anything but gentle… during entry, a parachute was used to slow the descent, and once near the surface, air bags were deployed and the probe dropped, bouncing several times before coming to rest.
The mission exceeded all expectations… more than 17,000 images were returned, chemical analyses was conducted on rocks and soils, and extensive weather data was received. And both the station and the rover outlived their expected design lives.
Pathfinder Atmospheric Descent and Landing
Mars Pathfinder Team Recalls July 4, 1997