30

The paper "Laser Technology in Photonic Applications for Space" by Denis Guilhot and Pol Ribes-Pleguezuelo highlights some of the problems of lasers in space: In the specific case of laser diodes, the indium used to package the laser chip could represent a risk in case of extreme temperatures ranges due to the indium creep behaviour that can lead ...


13

Yes, the pressure of the first stage exhaust is always at least slightly subatmospheric, because that gives the maximum average ISP over the whole burn time. Rockets with boosters attached (parallel staging) often operate at the lowest possible exhaust pressure that prevents the flow from detaching from the nozzle walls. Historically, the Summerfield ...


10

The sample return capsule is designed to keep its contents below 75 °C. It is a flight-proven design, reusing technology developed for the Stardust mission. The return capsule’s structure consists of a graphite-epoxy material covered with a Thermal Protection System making use of NASA’s PICA heat shield technology – Phenolic-Impregnated Carbon Ablator. PICA ...


8

Here's a quick comparison of the two missions. Differences to follow. OSIRIS-REx Name: Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer Lead Institution(s): NASA (USA), University of Arizona Principle Investigator (PI): Dante Lauretta (University of Arizona) Target: 101955 Bennu Launch date: 8 September 2016 Return ...


8

Just speculating here, but Osiris in an Egyptian myth ascended a ladder into the heavens. So it makes sense to name a probe (or a component thereof) after an "astronaut" from Egyptian mythology. Why Osiris as opposed to a host of other potential namesakes? That probably comes down to what letters they had available to make an acronym with. There are project-...


7

The image was taked by the OCAMS instrument. OCAMS uses CCD (Charge Coupled Device) focal planes. The charges generated by the incident light in each frame are transferred down the columns one pixel at a time. If there is an especially bright object, it may affect the remainder of the column. Note: OCAMS is a suite of cameras: PolyCam, MapCam, and ...


7

The line you are referencing is because the Earth is very bright on a "black" background. It happens as the light overpowers the image chip, similar to the Starburst pattern bright headlights make on dark nights.


6

OSIRIS-REx is packed all full of good stuff. I'll throw together a quick list of the scanning ones you're interested in. Also of note is that the entire spacecraft will be making that scanning motion shown in the gif, so as the asteroid rotates, all of these instruments will be able to have full coverage of it. OSIRIS-REx Visible and Infrared Spectrometer ...


6

SLC-40 and 41 are neighbors, no other pads in between. Some debris landed further away than SLC-41. They share some systems, e.g. the deluge system. The only good source I've found is this post by a member of the emergency response team. On Sept. 1, OSIRIS-REx was still in the vertical integration building next to the launch pad. The explosion ...


5

Satellites are finely tuned to work in a specific environment. Space is a tough environment, but usually pretty consistent. One of the things required is to keep the spacecraft at a certain operating temperature at all times, including on the ground and on the rocket. There are a few components that are particularly sensitive, most notably the batteries. ...


5

The streak is perfectly aligned to the vertical axis. Assuming that it hasn't been rotated, it is likely to be an artifact from imager chip, which may have saturated or overloaded - more charge/pixel than they can linearly process. However I noticed that the color of the streak is pure white, which is hard to understand unless it is caused specifically by ...


4

It appears to have been less of a decision based on concrete evidence and more one based on the convenience to do it. The OSIRIS-REx mission's main objective is to carry out a sample return mission from 101955 Bennu in the hopes of being able to further analyse the asteroid. According to the University of Arizona news the decision for the search came shortly ...


4

Largest original: https://www.asteroidmission.org/wp-content/uploads/2017/10/EGA_Plus_10_mapcam_Earth_Moon.png Blooming is vertical while streaking is horizontal: Some people use blooming and streaking interchangeably, while others use them as synonymous with each other. Some CCDs have anti-blooming gates which mostly inhibit the problem but can result in ...


4

The literature seems to indicate the answer is yes. There's some existing research on ejecta relative to other asteroids, but because of Bennu's irregular shape and small size those findings aren't as easily extended to the case you're interested in, so I'll focus only on Bennu-specific studies. According to McMahon et. al. in "Dynamical Evolution of ...


4

Bennu's hill sphere is 29.5 km roughly. The orbit is roughly circular, about 1.75 km above the center, or about 1.5 km above the surface of the asteroid. It is well inside of the Hill Sphere. This doesn't even compare to Dawn, which orbited about 35 km above the surface at closest, and that was with a very eccentric orbit. Hayabusa 2 isn't really orbiting ...


4

Money. Why spend more if you don't have to? Especially if you're in a competition with other similar proposals. Which it was.


4

Can OSIRIS-REx save us? No. I found no evidence that diverting the asteroid is a mission objective. The spacecraft is not equipped to influence the asteroid in any meaningful way. From the Wikipedia article you quoted: The science objectives of the mission are: Return and analyze a sample of pristine carbonaceous asteroid regolith in an ...


4

Rosetta: Optical, Spectroscopic, and Infrared Remote Imaging System OSIRIS-REx: Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer I haven't found an obvious connection, I'd say it's a coincidence. The origin of the name OSIRIS-REx: Michael Drake, the original principal investigator on OSIRIS-REx, first asked ...


4

Will this uncertainty in the mass of the sample affect the planning of the trajectory of the return capsule? Not by much, if at all. The burn commands to OSIRIS-ReX are commanded delta V rather than timed burns. Using timed burns does result in more and/or larger correction maneuvers than does using commanded delta V burns, even with spacecraft that don't ...


3

Relative to the third part of your question, OSIRIS-Rex will provide new data that may be helpful in more accurately estimating the future path of potentially hazardous asteroids by characterizing the Yarkovsky effect. The idea of the Yarkovsky effect is a body in space absorbs light from the sun. This absorbed energy is re-emitted as infrared radiation. ...


3

Yes, if you have a telescope or really good set of binoculars. The article you linked even states this: “It’s not going to be visible to the naked eye, but really any amateur astronomer with a half decent telescope should be able to do it,” the professor said. “Or a big lens on a regular camera like a telephonic lens, they should be able to pick it up and ...


2

Will they really be able to “see” OSIRIS-REx from Australia? With meteor cameras? Yes, we were! For all those who are interested, here is the preprint of the paper that resulted from the observations and is currently in review. Along with a conference abstract from AMOS 2018. arXiv: Recreating the OSIRIS-REx Slingshot Manoeuvre from a Network of Ground-...


2

This is to supplement the accepted answer by @Hobbes, and this information is from this link from that answer. The return capsule is a lot larger than I imagined, 81cm diameter, 50cm tall, so there is plenty of room for insulation.


2

For an unrelated purpose, I retrieved the Mission Requirements Document (OSIRIS-REx-RQMT-0001) for OSIRIS-REx. It details the minimum performance requirements for the mission. We can look at requirements section 3.3: Bennu Global Properties, Chemistry & Minerology Mapping Requirements. Here are the requirments: OSIRIS‐REx shall image > 80% of the ...


2

Found the solution thanks to uhoh. Use this URL to request Osiris-Rex ephemeris from NASA Horizons site: https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%27ORX%27&MAKE_EPHEM=%27YES%27%20&TABLE_TYPE=%27OBSERVER%27&START_TIME=%272018-10-01%27&STOP_TIME=%272018-10-28%27&STEP_SIZE=%271%20d%27%20&QUANTITIES=%271,9,20,23,...


2

Where could I get real time telemetries for OSIRIS-REX? For deep space missions, the spacecraft don't really "know" where they are and don't send position information back to Earth in telemetry as such. Instead, people here interpret signals from the spacecraft (mostly round-trip time delays and doppler shifts) to get line-of-sight distance and speed. ...


2

This article shows a picture of the whole OSIRIS-REx spacecraft and also shows an individual picture of the thruster. The name of this engine is the MR-106L thruster and it uses Hydrazine Monopropellant fuel and has a specific impulse of 229 - 235 seconds. These engines are used to control the pitch and yaw during the main engine burn. Here is an ...


2

They are not designed by the same groups at all. OSIRIS-REx was designed by Lockheed Martin, including the antenna. The diameter is 2.1m, and operates on 8445 MHz. TESS, on the other hand, has a 0.7 m antenna built by Orbital-ATK (Now Northrup Grumman, but...) The frequency is in the Ka band, which is 26.5- 40 GHz. Basically they look a lot alike because ...


1

According to a press release on the official website for OSIRIS-REx, These images were captured over approximately a five-minute period. The imaging sequence begins at about 82 feet (25 meters) above the surface, and runs through the back-away maneuver, with the last image in the sequence taken at approximately 43 feet (13 meters) in altitude – about 35 ...


1

Wikipedia covers this. The 1 in 1410 probability comes from Long-term impact risk for (101955) 1999 RQ36 in 2009 which notes... The analysis of impact possibilities so far in the future is strongly dependent on the action of the Yarkovsky effect, which raises new challenges in the careful assessment of longer term impact hazards. With better ...


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