NASA’s Dawn spacecraft has returned new images captured on approach to its historic orbit insertion at the dwarf planet Ceres. Dawn will be the first mission to successfully visit a dwarf planet when it enters orbit around Ceres on Friday, March 6.
This image was taken by NASA’s Dawn spacecraft of dwarf planet Ceres on Feb. 19 from a distance of nearly 29,000 miles (46,000 kilometers). Credit: NASA/JPL-Caltech/UCLA/MPS/ DLR/IDA“Dawn is about to make history,” said Robert Mase, project manager for the Dawn mission at NASA’s Jet Propulsion Laboratory in Pasadena, California. “Our team is ready and eager to find out what Ceres has in store for us.”
Recent images show numerous craters and unusual bright spots that scientists believe tell how Ceres, the first object discovered in our solar system’s asteroid belt, formed and whether its surface is changing. As the spacecraft spirals into closer and closer orbits around the dwarf planet, researchers will be looking for signs that these strange features are changing, which would suggest current geological activity.
“Studying Ceres allows us to do historical research in space, opening a window into the earliest chapter in the history of our solar system,” said Jim Green, director of NASA’s Planetary Science Division at the agency’s Headquarters in Washington. “Data returned from Dawn could contribute significant breakthroughs in our understanding of how the solar system formed.”
Dawn began its final approach phase toward Ceres in December. The spacecraft has taken several optical navigation images and made two rotation characterizations, allowing Ceres to be observed through its full nine-hour rotation. Since Jan. 25, Dawn has been delivering the highest-resolution images of Ceres ever captured, and they will continue to improve in quality as the spacecraft approaches.
Astronomy Talk: America’s Space Program – NASA’s Roadmap to Tomorrow’s Missions
This image was taken by NASA’s Dawn spacecraft of dwarf planet Ceres on Feb. 19 from a distance of nearly 29,000 miles (46,000 kilometers). Credit: NASA/JPL-Caltech/UCLA/MPS/ DLR/IDANASA Administrator Charles Bolden will discuss America’s space program and the challenges the agency faces for the missions of tomorrow. Using a stepping stone approach that builds on the capabilities of our unique orbiting laboratory – the International Space Station – the growing abilities of commercial providers to reach space, and a new rocket and crew vehicle to travel to deep space, NASA is extending human reach into the solar system even as its amazing science missions are rewriting textbooks about our universe and inspiring the next generation of explorers.
The agency currently has spacecraft speeding toward Jupiter and Pluto and roving on Mars, and is searching for planets that could potentially harbor life beyond our solar system. An unprecedented mission to capture and redirect an asteroid to an orbit near to Earth is in the planning stages, and the Space Launch System and Orion Crew vehicle are reaching new milestones in development to take astronauts to an asteroid and on to Mars.
NASA has been a 1/6 partner in the W. M. Keck Observatory since 1996 and it is an honor to offer this program to the community.
The Kepler team today reports on four years of observations from the W. M. Keck Observatory targeting Kepler’s exoplanet systems, announcing results this week at the American Astronomical Society meeting in Washington. These observations, from Keck Observatory on the summit of Mauna Kea, confirm that numerous Kepler discoveries are indeed planets and yield mass measurements of these enigmatic worlds that vary between Earth and Neptune in size.
Chart of Kepler planet candidates as of January 2014., credit NASA AmesMore than three-quarters of the planet candidates discovered by NASA’s Kepler spacecraft have sizes ranging from that of Earth to that of Neptune, which is nearly four times as big as Earth. Such planets dominate the galactic census but are not represented in our own solar system. Astronomers don’t know how they form or if they are made of rock, water or gas.
Using one of the two world’s largest telescopes at Keck Observatory in Hawaii, scientists confirmed 41 of the exoplanets discovered by Kepler and determined the masses of 16. With the mass and diameter in-hand, scientists could immediately determine the density of the planets, characterizing them as rocky or gaseous, or mixtures of the two.
A team of astronomers has found the first Earth-sized planet outside the solar system that has a rocky composition like that of Earth. This exoplanet, known as Kepler-78b, orbits its star very closely every 8.5 hours, making it much too hot to support life. The results are being published in the journal Nature.
Artist impression of the planet Kepler-78b and its host star. Credit: Karen Teramura (UH/IfA)This Earth-sized planet was discovered using data from NASA’s Kepler Space Telescope, and confirmed and characterized with the W. M. Keck Observatory.
Every 8.5 hours the planet passes in front of its host star, blocking a small fraction of the starlight. These telltale dimmings were picked up by researchers analyzing the Kepler data.
The team led by Dr. Andrew Howard (Institute for Astronomy, University of Hawaii at Manoa) then measured the mass of the planet with the Keck Observatory on Mauna Kea, in Hawaii. Using the ten-meter Keck I telescope fitted with the HIRES instrument, the team employed the radial velocity method to measure how much an orbiting planet causes its star to wobble, to determine the planet’s mass. This is another excellent example of the synergy between the Kepler survey, which has identified more than 3,000 potential exoplanet candidates, and Keck Observatory, which plays a leading role in conducting precise Doppler measurements of the exoplanet candidates.
We put it together in very short notice. Fortunately a webcast is pretty easy to put together.
Keck is hosting a sizable team of folks who are here to observe comet ISON. Astronomers from several institutions are participating in the NASA Comet ISON Observing Campaign. They have a total of 6½ nights, but only the last few hours of each night as the comet rises in the dawn. Comet C/2012 S1 ISON is starting to encounter significant publicity, we may as well take advantage of this.
It was a lot of fun. I particularly like the spot (41:00) where I made the mistake of saying spectra were not very pretty to look at in a room full of spectroscopists. These folks love spectra and quickly corrected me, leading to a nice discussion on why spectra are so valuable to astronomy, often more valuable than photos.
The video is embedded below. A lot of good information about comet ISON, indeed about comets in general. Nothing like having a room full of comet experts…
A spectacular image of Saturn from above. Even better, the image was assembled by an amateur astronomer, Gordan Ugarkovic, working with Cassini imagery taken on October 10th. Click on the image to zoom in, then zoom in some more! You can see exquisite data in the polar cloud-tops and in the rings. Keep an eye out for the shepherd moons at the edges of the various rings…
This portrait looking down on Saturn and its rings was created from images obtained by NASA’s Cassini spacecraft on Oct. 10, 2013. It was made by amateur image processor and Cassini fan Gordan Ugarkovic. This image has not been geometrically corrected for shifts in the spacecraft perspective and still has some camera artifacts.The mosaic was created from 12 image footprints with red, blue and green filters from Cassini’s imaging science subsystem. Ugarkovic used full color sets for 11 of the footprints and red and blue images for one footprint. Credit: NASA/JPL-Caltech/Space Science Institute/G. Ugarkovic
The aircraft is rather unremarkable, a standard small jet sitting among many similar aircraft at the Kona airport. It is the NASA colors and the odd pod hanging underneath that belies that this jet is somewhat unusual. This aircraft does not shuttle passengers across the country, it is home to a unique instrument called UAVSAR.
NASA aircraft equipped with UAVSAR podAfter giving the JPL staff a tour of Keck, they reciprocated and offered a tour of their aircraft. An offer that we readily accepted! After three days of watching the jet fly overhead, an opportunity to to see this aircraft up close was not to be wasted.
During this deployment the aircraft has quartered the Big Island, mapping any changes in the landscape on this volcanically active land. The acronym UAVSAR stands for Uninhabited Aerial Vehicle Synthetic Aperture Radar. As the name implies the system is designed to operate from a UAV, but it is currently installed in a crewed Gulfstream III aircraft.
Color-enhanced UAVSAR interferogram images of Hawaii’s Kilauea volcano, image credit: NASA/JPL-CaltechThe system is capable of sub-centimeter accuracy, mapping the surface of our planet with a reconfigurable, polarimetric L-band synthetic aperture radar (SAR). This can reveal precise information about the shape of the land, moisture content of the soil, vegetation differences and more. Making multiple passes of the same area allows study of subtle changes in the terrain due to erosion or volcanic activity. Flying at 12,000 meters (40,000ft) the aircraft must navigate with exceptional accuracy to allow the radar to gather the data. A custom autopilot flies the aircraft through a 33 foot (10 meter) “tube” in the air between two GPS waypoints.
For this mission it is this volcanic island that is the target. As any islander knows we live on a rock that moves. The island settles into the sea, slides into the ocean, and swells where magma pushes its way into the volcano. Each year they return to Hawai’i to re-map the island, this is the fourth year they have returned to check the changes wrought by the volcanoes.
The JPL/NASA folks have completed their mission to the island for the year. Our tour was the morning they were due to depart, flying back to the Dryden Flight Research Center in California.
UAVSAR radar podThe aircraft is not as jammed with electronics as I envisioned. Boarding the plane one finds a few equipment racks and a number of comfortable seats available for the folks that have to tend the electronics through ten hour missions. It is an odd combination of custom electronics built to aerospace standards and off-the-shelf electronics fastened into the racks, including computers, monitors and ethernet routers. Much of the gear is used for simply monitoring the instrument, rather than needed for the radar. One can see how the system could be installed in a smaller UAV.
Hanging underneath the aircraft is the pod containing the radar itself. Bright white, the pod sports a flat antenna down the port side for the sideways looking beam. A trio of scoops on the front ram air through the pod to keep the electronics cool.
We chatted with the flight crew and the radar team learning about the instrument and aircraft. They travel all over the US and sometimes around the globe. They have mapped volcanoes in Alaska and Japan, glaciers in Iceland, measured oil spills, and scanned regions effected by major earthquakes. We noted that they had a fascinating job, while they said the same right back at us.
After the tour our hosts kicked us off the plane and began start-up for their hop back to the mainland. We got the data disks with the GPS data we needed for our tests and traded business cards and contact info. I will have to keep my eye out for the results of this year’s Big Island deployment.
