Data & Results
The antenna on the New Horizons spacecraft.
The New Horizons spacecraft has a high-gain antenna that transmits scientific data about dust back to Earth as radio waves. Moving at the speed of light, it still takes the data hours to arrive at Earth. For example, from Pluto, the data will take four hours to arrive at the NASA Deep Space Network here on Earth. The Network receives the data and sends it out to the New Horizons team.
Data from SDC will move scientific understanding of dust forward in various ways.
Comparing with past mission data
Scientists often calibrate data from one instrument to another to create a more continuous and understandable data set. If two sets of data disagree or don't match, scientists can use that information to improve future instruments.
Scientists have already completed initial comparisons SDC data to existing data. The first results, published in Geophysical Research Letters, indicate that SDC measurements of dust inside 5 astronomical units agree well with the earlier measurements made by the Galileo and Ulysses missions.
Scientists will not be comparing SDC data on dust further out than 18 astronomical units to other missions because such data doesn't exist. Instead, scientists will be testing their theoretical understanding of dust in the solar system, adjusting their theories to accommodate the new data.
Improving computer simulations
Scientists will also compare the SDC data retrieved to several computer simulations of expected dust distribution and density. Computer models of the dynamics of Kuiper-Belt dust grains show that dust tends to get trapped near Neptune in sync with the planet's orbit. SDC will take data in this region so that scientists can improve their computer models with real data.
Students working on the SDC mission are also reproducing computer models in-house with higher spatial resolution and particle statistics, in the hopes of allowing further detailed comparison of SDC measurements with theory about formation and evolution of dust in the Kuiper Belt and the solar system.
Data that SDC captures
The detector panels of the SDC are being assembled in this image.
Each time a dust particle hits a detector, the electronics store five pieces of data:
- Detector number that the dust particle hit
- Minimum sensitivity of the detector
- Size of the electronic pulse generated, which is turned into the particle size using ground calibrations
- Time of impact
- Time of day the data was streamed to Earth
These data allow scientists to analyze the time and size of all the dust particles that impact SDC along its voyage to the Kuiper Belt.
Results from the data
A visualization of data generated from the SDC.
After scientists receive all the data from the SDC and ensure that the instrument has worked properly, the next step is to analyze the data.
Data analysis can be difficult. If the data differs greatly from what scientists were expecting to find, they have to decide whether their instrument was wrong, or whether their theories were wrong. If the data is what was expected, scientists have to make sure they've analyzed it correctly so no bias occurs. If scientists come to the conclusion that their data are valid and good, then they determine what new information they have gained.
It could take years, or even decades, from the time the instrument records the data and a scientist publishes a paper about the findings. The process from data analysis to increased scientific understanding is long, but rewarding.
Selection of publications
Andrew Poppe, David James, Brian Jacobsmeyer, and Mihály Horányi. 2010. First results from the Venetia Burney Student Dust Counter on the New Horizons mission. Geophysical Research Letters, Vol. 37, L11101, 5 PP. doi:10.1029/2010GL043300