Highlights
This page will be dedicated to a few of the outstanding science highlights generated through the use of NASA's R&A (including DA) funds. Please send us information on a result that you think is especially worth noting, and include the program from which funding was received. Feel free to submit your own work or that of a colleague who may be too shy to do so themselves. The Highlights will be posted in a random order, and we will number them sequentially only to help you find them as the list grows. You can find an index of the highlights here with a short version of the title.
- Voyager Squashes View of Solar System
- Stellar Baby Boom
- Hydrocarbons in the other “Lake Ontario�
- The Golden Age for Satellite Imaging of Pollutants?
- A GLIMPSE of the Milky Way
- Two of the Milky Way's Spiral Arms are Missing!
- Terra/Aqua Satellite Image Reveals Cyclone Nargis Floods
- The Phoenix Has Landed
- Tiny meteorite whiskers with astronomical implications
- Titan's hidden ocean
- Water and Methane in the atmosphere of an extra-solar planet
- Ring around Rhea
58. Voyager Squashes View of Solar System
Scientists using data from NASA's Voyager 2 spacecraft have observed the bubble of solar wind surrounding the solar system is not round, but has a squashed shape, according to recent data published as part of a series of papers in the July 3 issue of Nature. In the News and Views piece “Solar System: A shock for Voyager 2� J. R. Jokipii introduces the five papers about the heliospheric termination shock measured by Voyager 2, thirty years after its launch. The five letters are:
- “Cool heliosheath plasma and deceleration of the upstream solar wind at the termination shock,� Richardson et al;
- “Mediation of the solar wind termination shock by non-thermal ions,� Decker et al.;
- “An asymmetric solar wind termination shock,� Stone et al.;
- “Magnetic fields at the solar wind termination shock,� Burlaga et al.; and
-  “Intense plasma waves at and near the solar wind termination shock,� Gurnett & Kurth.
Astronomers have uncovered an extreme stellar machine -- a galaxy in the very remote universe pumping out stars at a surprising rate of up to 4,000 per year. In comparison, our own Milky Way galaxy turns out an average of just 10 stars per year.
The discovery, presented by Caputi et al., in “The Optical Spectra of 24 μm Galaxies in the COSMOS Field. I. Spitzer MIPS Bright Sources in the zCOSMOS-Bright 10k Catalog� which appeared in the June 20 2008 issue of the Astrophysical Journal, (Vol 680 pages 939–961), was made possible by several telescopes including NASA's Spitzer Space Telescope. Please see the web release “Rare 'Star-Making Machine' Found in Distant Universe“ on the NASA web page.
56. Hydrocarbons in the other “Lake Ontario�
In the letter “The identification of liquid ethane in Titan's Ontario Lacus� by R. H. Brown et al., in the 31 July 2008 (Vol 454 #7204) issue of the journal Nature presents observations suggesting that Ontario Lacus, a lake-like structure near Titan's south pole, is filled with liquid ethane, among other things. The News and Views piece Planetary science: Organic lakes on Titan by François Raulin puts this discovery of the long searched for liquid hydrocarbons in context. The data is from NASA’s Cassini Spacecraft.
55. The Golden Age for Satellite Imaging of Pollutants?
The cover of the August 2008 issue of Environmental Health Perspectives (Volume 116, Number 8) shows NASA satellite images of how carbon monoxide from agricultural fires in South America and Africa crossed the Atlantic Ocean in late summer 2005, mixed, and returned home. The Focus article “The Global Sweep Of Pollution: Satellite Snapshots Capture Long-Distance Movement� describes how satellite data are being used to formulate a clearer picture of the global transport of pollutants. It Includes data from CALIPSO Terra, and other satellites.
54. A GLIMPSE of the Milky Way
The Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) Spitzer team released two multi-gigapixel infrared images of the Milky Way on June 4th at the AAS meeting From this an annotated zoomable version of the images was made available on the web. You can even identify a feature you like and send the link to a friend. The second part of the project is to provide it as a standalone (internet free) version for science centers and libraries which will come later this year. To try it out go to http://www.alienearths.org/glimpse/
53. Two of the Milky Way's Spiral Arms are Missing!
New images from NASA's Spitzer Space Telescope are shedding light on the true structure of the Milky Way, revealing that it has just two major arms of stars instead of the four it was previously thought to possess.
The science team was led by Robert Benjamin of the University of Wisconsin and this project is being presented at the American Astronomical Society meeting in St. Louis. For more information please see the SMD chief scientist’s highlight, downloadable as a PDF file here, or read the article at Space.com, or the JPL web release.
52. Terra/Aqua Satellite Image Reveals Cyclone Nargis Floods
In early May, Cyclone Nargis caused widespread flooding in Myanmar (Burma). Determining the
extent of flooding can be difficult; clouds often obscure satellite observations, and muddy-brown
floodwaters typically blend in with the surrounding landscape, especially fallow cropland. A
standard satellite image can provide an approximation of the flood extent, but not an exact outline.
However, multiple sources of information can be combined to provide a better picture of flooded
areas. In the image at left, which combines observations taken by NASA’s Terra and Aqua satellites
on May 5, 2008, by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors shows that
flooding appears to be more intense in areas with fewer trees. For more information please see the
NASA web feature, or the articles at Earth Observatory News and SpaceRef.com.
On May 25th shortly after 4:30 pm PST (and curiously also Mars time) the Phoenix Mission landed gracefully on Mars. Named after Phoenix, the mythological bird that rose from the ashes of its ancestor, this Mars mission was named in honor of its predecessor Mars polar lander, which had a similar destination and mission but was lost on entry, descent or landing. This mission which is groundbreaking both literally and figuratively has landed far farther north of the Martian equator around which all prior landers and rovers have touched down. Landing as it does in the Martian equivalent of the Yukon Territories, Phoenix is likely to encounter frost at the surface, and with luck will find water ice and organic molecules below. The image above shows a (HiRISE) image, taken from orbit, of Phoenix descending on a parachute. This is the first time an image has been taken of a spacecraft descending to the surface of Mars. This images can be found at the Phoenix web page, and images of the surface can be found at the image gallery.
50. Tiny meteorite whiskers with astronomical implications
In the report “Graphite Whiskers in CV3 Meteorites� in the journal Science (320, 91 – 93) Fries and Steele propose that
graphite whiskers could easily have been launched into interstellar space by
bipolar outflows of forming solar systems. Graphite whiskers have been postulated to play a role in the
near-infrared (near-IR) dimming of type 1a supernovae, as well as in the
thermalization of both the cosmic IR and microwave background and in galactic
center dimming between 3 and 9 micrometers. For more information see the
Astronomy Perspectives piece “Small-Scale Observations Tell a Cosmological Story� by Philip Bland.
This work was funded by NASA Sample Return Laboratory Instrument and Data Analysis, Astrobiology Science and Technology for Exploring Planets, and Astrobiology Institute programs.
49. Titan's hidden ocean
Years of Cassini observations have allowed Ralph Lorenz and colleagues to show that Titan's rotational period is changing and is different from its orbital period. In their report "Titan's Rotation Reveals an Internal Ocean and Changing Zonal Winds" in the Journal Science (2008) 319, 1649-1651 suggest that an ocean may be hiding beneath Titan's thick atmosphere and icy surface, but other explanations of the observed results cannot yet be ruled out. For more information you can follow the link to the original article, above, read the planetary science perspectives piece "Titan's Hidden Ocean" by Sotin & Tobie, NASA's press release, or one of many online articles including at Scientific American, Space.com, and Sciencedaily.
Dr. Lorenz is supported by the Cassini Data Analysis program.
48. Water and Methane in the atmosphere of an extra-solar planet
In an article accepted in the journal Nature Professor Mark Swain and Gautam Vasisht of Caltech, and Giovanna Tinetti of University College London, UK, report the detection of methane and confirmed an earlier tentative detection of water vapor in the atmosphere of giant planet HD 189733b based on Hubble Space Telescope observations. This marks the first detection of an organic molecules on a planet outside our solar system. However, the authors note that "The giant planet lies too close to its parent star for the methane to signal life." Interestingly they also note that the "combination of water and organic molecules would be a promising one for life if it were found in a less hostile spot than the atmosphere of a searing gas giant." For related materials see the NASA press release, 'Organic molecules found on alien world for first time' by Stephen Battersby for New Scientist online, and for some perspective a recent article in the Washington Post online which is featured on our science matters page.
In the report "The Dust Halo of Saturn's Largest Icy Moon, Rhea" in the journal Science (319. 1380 -
1384) Jones et al., show that Rhea has an equatorial debris disk that, based on Cassini
measurements, "in the form of grains and boulders up to several decimeters in size." More
information can be found in the Science news of the week piece "Planetary Science: Electron Shadow
Hints at Invisible Rings Around a Moon" by Richard A. Kerr in popular science publications such as
Sky and Telescope, and on news websites like CNN.com.