Astronomy Department Research Highlights
Research in the Department of Astronomy is conducted under the auspices of either the
Institute for Astrophysical Research or the
Center for Space Physics. On this page we will call attention to some of our more recent projects or larger ongoing projects. In most instances clicking the image will direct you to a higher resolution version of the image, clicking the title will take you to a related web site; click on the name of the researcher to go to his or her home page.
GLIMPSE (Galactic Legacy Infrared Mid-Plane Survey Extraordinaire) was one of the experiments using the Spitzer (formerly called SIRTF, for Space Infrared Telescope Facility) satellite and telescope. GLIMPSE conducted a survey of the inner part of our galaxy, the Milky Way. Professors Bania, Clemens, and Jackson were members of the GLIMPSE team.
The Galactic Ring Survey (GRS) is a survey of 13CO molecular line emission, tracing the star-forming molecular clouds in the Milky Way galaxy.
Although the 5 kpc ring in the inner Milky Way Galaxy was discovered over 25 years ago, most of its properties remain unknown. The main objectives of the Galactic Ring Survey are to:
- catalog the molecular clouds and cloud cores,
- establish kinematic distances to many clouds and their associated Young Stellar Objects,
- determine their sizes, luminosities, and distributions,
- and determine the structure of the inner Milky Way, especially that of the 5 kpc ring.
Cluster of Galaxies Abell 2052
X-ray image from the Chandra X-ray Observatory of the central region of the cooling flow cluster of galaxies, Abell 2052, with contours of radio emission superposed. In the cooling flow model, large amounts of gas in the intracluster medium are expected to cool radiatively and flow to cluster centers. However, the expected quantities of very cool gas and associated forming stars are not seen (the “cooling flow problem”). Heating from radio sources associated with supermassive black holes at the centers of galaxies is now the leading candidate for explaining the lack of cool gas seen at cluster centers. (credit:
Prof. Blanton)
Spiral Galaxy
A large spiral galaxy and its satellite, obtained from the Sloan Digital Sky Survey. Professor
Brainerd and graduate student Ingolfur Agustsson are using this and about 3000 similar systems
to study the location and orientation of satellite galaxies with respect to the primary galaxies about which they are orbiting.
Saturn Aurora
Hubble Space Telescope (HST) images of Saturn and its polar auroral emissions on 24, 26, and 28 January 2004. Each of the three images of Saturn combines ultraviolet images of the south polar region (to show the auroral emissions) with visible wavelength images of the planet and rings. The HST images were obtained during a campaign by the Cassini spacecraft to measure the solar wind approaching Saturn and the Saturn kilometric emissions. The strong brightening of the aurora on 28 January corresponded with the recent arrival of a large disturbance in the solar wind. These results are presented in three letters in the February 17, 2005 issue of
Nature. (credit: Z. Levay and J. Clarke:
cover)
A near-infrared imager, spectrometer, and polarimeter for the Perkins Telescope. Mimir was designed, fabricated, and tested by teams at Boston University and Lowell Observatory with support provided by NASA, NSF, and the W.M. Keck Foundation. Mimir saw first light on August 19, 2004.
Sounding Rockets
The BU sounding rocket programs use small suborbital rockets to observe the earth, the solar system, and beyond as part of NASA’s low cost access to space program.
The Cluster mission, consisting of four identical spacecraft flying in formation between 25000 and 125000 km above the Earth, is studying the planet's magnetic field and electric surroundings in three dimensions. In particular, it is looking at the effects of the solar wind, the hot wave of energy produced by the Sun, which buffets Earth's protective magnetosphere. This wind often breaks through at the poles, producing auroras. Cluster was launched in July and August of 2000.
An MHD computer simulation of a solar coronal mass ejection propagating through interplanetary space. Color indicates plasma density (cm-3) and shows the compressed plasma behind the shock ahead of the CME. The magnetic field lines show how the field in the CME is twisted into a flux rope that connects back to the sun (red dot). This simulation was performed with models used within the
Center for Integrated Space Weather Modeling (CISM), an NSF Science and Technology Center led by Boston University.
The MACCS magnetometer site at the reservoir at Pangnirtung, Baffin Island, Canada. MACCS is an array of magnetometers that monitors ionospheric currents at high magnetic latitudes in Canada. It is jointly run by Boston University and Augsburg College.
NGC 891
Image of NGC 891, obtained by Kenneth Janes and Jason Eastman using the
PRISM instrument on the 1.83-meter Perkins telescope at Lowell
Observatory.
Using our telescope at the
“BU Station”
at the McDonald Observatory (Texas) and BU detector systems attached to the 3.6 m AEOS telescope on Haleakala (Hawaii), studies are conducted of the escaping atmospheres of solar system bodies. Imaging is done at sodium wavelengths, a convenient tracer for the more abundand gases that are sputtered from surfaces with sufficient energy to escape the weak gravity of their parent bodies. The examples shown here are: the large-scale exosphere of the Moon, the patchy atmosphere close to Mercury and the highly structured escaping exosphere of Jupiter’s moon Io.
Comparative studies of the same process on two planets offer ways to explore and to constrain physical mechanisms in atmospheric science. Two cases are shown, one giving the response to the same solar flare upon the ionospheres of Mars and Earth. This study was made possible by the Mars Global Surveyor satellite at Mars, groundbased ionospheric radars on Earth, and X-rays monitored by the GOES spacecraft. The second example compares effects of sudden introductions of water vapor clouds carried into the Earth’s ionosphere by NASA sounding rockets — releases that cause “ionospheric holes” via enhanced plasma loss chemistry. Such effects are remarkably similar to proposed ionospheric depletion scenarios at Saturn — where the water influx is due to sputtering from Saturn’s rings and water jets from its moon Encelades.
|
