OPT & Osiris REx - Target Asteroids
What is Osiris-REx & Target Asteroids!?
OSIRIS-REx is NASA's sample return mission to near-Earth asteroid (NEA) (101955) Bennu. This mission, set to launch in September of 2016, will briefly touch Bennu to collect invaluable samples from this carbon-rich or carbonaceous asteroid. Analysis of the sample will help planetary scientists gain a greater understanding of the early Solar System and its evolution. It may also bring us clues about the organic compounds that may have seeded early life on Earth. Organic molecules have previously been found in meteorite and comet samples, indicating that some ingredients necessary for life can be created in space. Scientists selected Bennu because it is a carbon-rich near-Earth asteroid likely to contain regolith (a layer of loose rock), is made of carbon-rich material unprocessed since early in the Solar System, and is accessible by sample return spacecraft in a reasonable time.
The OSIRIS-REx spacecraft is equipped with a suite of cameras and instruments that will allow complete mapping of Bennu and spectral analysis of its minerals. Along with Earth-based astronomical observations, the visit to Bennu will help scientists understand the process by which Main Belt asteroids may become near-Earth asteroids.
At least 60 grams (0.13 pounds) will return to Earth in 2023, landing in Utah's Test and Training Range. NASA will transport the sample to Johnson Space Center‘s dedicated curation facility which will distribute samples to scientists worldwide for generations of detailed studies.
Which Asteroids Should I Target?
Carl HergenrotherCarl Hergenrother, the OSIRIS-REx mission asteroid astronomy lead and Target Asteroids! co-lead, has compiled a list of 80 asteroids which are likely to be targeted for spacecraft sample return missions or are needed to expand our understanding of the near-Earth asteroid population. It is a dynamic list that changes as we learn more about these near-Earth asteroids and new ones are discovered. Many of these objects were selected using the following perameters:
- absolute magnitude (H) < 21.5
- objects with H > 21.5, corresponding to diameters greater than ~150 meters, are rapid rotators with rotation periods on the order of minutes not likely to have retained small soil particles on the surface (regolith)
- perihelion distance (q) > 0.8AU
- q less than 0.8 AU may require spacecraft thermal upgrades
- aphelion distance (Q) < 2.0AU
- Q greater than 2.0 AU requires spacecraft power upgrades
- inclination (i) < 8º
- constraints on q, Q, and i are also required to limit the delta-‐V budget of a sample return mission
Since many of the targets for sample returns are very faint, the list was expanded to include many Main Belt asteroids and NEAs that can be used as analogues for Bennu. Many of the analogous asteroids will be able to be observed with smaller aperture telescopes, which opens the program up to a wide number of astronomers.
How Do Your Data Help?
Professional astronomers have access to the largest, most powerful and technologically advanced telescopes in the world - some with mirrors measuring many meters, so you may wonder how your observing and imaging sessions will help. You help by being part of a group collecting a very large number of photometric observations (measured from images). When these data are combined, they provide many more data for scientists to use.
Amateur astronomers are able observe more often, reach observing geometries not accessible to large observatories, and, provide worldwide geographical coverage – all of which fill in data gaps. Your observation may be the only one received for a particular asteroid on any given night. It becomes the anchor point until additional observations can be made. Every observation is important.
As a Target Asteroids! partner, OPT is committed to helping expand the mission’s efforts to reach as many astronomers as possible. Find out more about this citizen science project go to: http://osiris-rex.lpl.arizona.edu/?q=target_asteroids
To register your interest, visit the Target Asteroids! Observer Registration.
More about this exciting Citizen Science project:
The International Astronomical Search Collaboration - Target Asteroids! Observating Campaign - LAST DAY TO SIGN UP IS 10/10/13