Frequently Asked Questions

Q. Could you check the candidate/image?

A. Due to the large number of reviewers and limited time for SPACEWATCH® staff for correspondence, we regret that the fmo webmaster can no longer reply to every inquiry about specific images or objects. We will endeavor to continue to respond to problems with the operation of the fmo service. Thank you for your understanding.

Q. I did not submit this candidate but I have jpg image name. Could you take a look to see if this is a real FMO?

A. Unfortunately, if you did not submit the candidate, we can not track it down. Please be sure to submit any candidate you think may be a real FMO.

Q. I have FMO membership but it seems to be deactivated.

A. If you do not log in to the FMO membership page for more than two months, your account will be deactivated. To reactivate your account, please contact the FMO webmaster. Please note that it might take few days to reactivate your account.

Your account will be deactived if you resubmitted more than five resubmissions in one night. To ease the mosaic observers work load, we deactivate reviewers who resubmit more than five candidates in one night. The deactivated accounts can be redeemed by sending email to the FMO webmaster. However, please note that reactivating accounts may take more than a few days. Please check our news page:

(https://spacewatch.lpl.arizona.edu/fmo/news)

for examples of real fmos and avoid exceeding the number of resubmissions.

Q. I sent webmaster email but never got reply.

A. Please check your email account setup. Do you block email from certain addresses? In that case, we can not reach you even we try to reply your mail.

Q. The music option does not work.

A. If your browser is set to block popup windows, then the music window will not come up. Please check your browser's "preferences" to allow popup window.
(e.g. Edit/Preferences/Privacy&Security/Popup Windows/Block uncheck the box or add fmo site in "allowed site" list).
If above does not work, then you might need to install plug-ins. To test browser, goto this URL:

http://www.piano-midi.de/bach.htm

Does your browser play the music? If not, then you need to install plug-ins for audio/x-midi and audio/mid on your browser.

Q. How do I sign up for the FMO membership?

A. Please refer to "HOW TO BECOME A MEMBER" page.

Q. How many members login to review images per night?

A. Typically 20 to 30 reviewers review each night.

Q. I applied the FMO membership, how do I review images?

A. Please click "MEMBERS PAGE" on the navigation menu as shown to the left. Once you are logged in you can see the image status. If the image status indicates that images are available, then you can start reviewing images. If you are reviewing for the first time please read the image review instructions. Its link is above the "REVIEW TOOL" button in the review tool window. For further detail on when images become available throughout the night please refer to Image Process Flow.

Q. I forgot my login name and/or password. What should I do?

A. You can go to forgot password page or send email to:

webmaster "at" fmo.lpl.arizona.edu

Q. I requested reminder email for my login name and password but I never received it.

A. Your email server maybe rejecting email from our email account. Please make sure that you are allowing email from fmo.lpl.arizona.edu to come through. Another option is to send email to:

webmaster "at" fmo.lpl.arizona.edu

Q. What is MPC name?

A. MPC name is fmo reviewer's name we submit to the MPC (The Minor Planet Center) for discovery credit when reviewer finds fmo. The MPC name has to be in the form of:

First name initial. middle name initial (if you have one). FULL REAL last name (family name). For non-English character, please refere to:

http://cfa-www.harvard.edu/iau/info/NonEnglish.html.

Q. Is there a newsgroup?

A. 2005 July 19 - we were notified of a newsgroup for interested individuals to exchange information. The FMO Webmaster doesn't monitor this newsgroup nor does SPACEWATCH® endorse it. Use at your own risk.

Q. When I log on, the telescope status is always closed.

A. The telescope is open 20 days out of each lunation (moon cycle) and produces images a regular intervals during local darkness (see Image Process Flow for further detail). Please refer to Statistics page for the recent operating nights. The telescope closes during inclement weather and around full moon. We offer links to weather pages to help reviewers decide if waiting for images is warranted.

Q. I live in Saskatchewan, Canada. What time would I need to be up during the night to review images?

A. The time of image downloads varies with the seasons (varying with the changes in sunset and sunrise) as well as with each individual observer's habits. We designed the page Telescope Status Guidelines (accessible from the Weather Conditions page as HOW TO USE) to help reviewers understand the effects of weather, but the page also gives links to descriptions of universal time (UT) and indicates how to gauge the number of hours until images can be expected.

Q. Why don't you give a better idea of when the telescope will open and when images will be downloaded?

A. Even the observer doesn't know for certain that he/she will be able to open the telescope at the expected time. The wind may come up as the sun sets, the humidity might rise or, infrequently, the equipment may not cooperate. We actually do give a substantial number of predictive indicators on the members 'Welcome' page and in the 'Weather Conditions' popup window accessed from that same page. To help members better understand how to use the information we offer, the 'Weather Conditions' popup now as a HOW TO USE link that will guide the member in using the tools we offer.

Q. What does "DOWN FOR FULL MOON" mean?

A. SPACEWATCH® is an asteroid survey group that specializes in smaller and more distant potentially hazardous asteroids. As a result, our telescopes and detectors are more sensitive to the effects of moonlight and we shut down for about four days on either side of the full moon each lunation.

Q. Would it be a good idea for me to get out my personal telescope for some of this?

A. Many, if not most, of the FMOs we discover can be recovered with the typical amateur telescope using the 'track and stack' method ONCE the object has a 24-hour arc. The first recovery (pre 24-hour arc) of a new FMO typically requires a large field of view due to the uncertainty of its orbit so recovery may be difficult for the average system.

Q. When I log on, there are never images available.

A. Each image is offered for review only once to avoid problems giving proper MPC credit in the event of an FMO discovery/recovery. We have so many reviewers that the images are quickly reviewed so you may need to watch the page carefully to catch unreviewed images. By reading the Image Process Flow and understanding the image download timing you can ensure that you will be logged in and watching when images become available (and not waste time watching when no images are expected.)

Q. Your webpage says that images are posted every 2.5 hours, but I saw them appear more frequently.

A. The 2.5 hours is the longest wait you should expect...although there are uncommon situations that will lead to longer waits. We describe the acquisition process in Image Process Flow webpage. The download time is dependent on the observer processing the data after acquiring the third pass - this means that the timing is dependent on the observer's preferences, e.g. processing each center as the third pass is acquired or waiting until the full region (ten centers) has been acquired. Due to these (and other) variations in observer behavior we can only give a 'likely' maximum wait. If new images do not come down WITHIN 2.5 hours chances are that the image quality is poor or the telescope is closed...but not definite.

Another source for timing information is Telescope Status Guide.

Q. On the members page it says there are 640 unreviewed images, but when I click the review tool it gives me popup window saying no image available. Why?

A. Images are reviewed through the night, reviewers take less than 30 minutes to process each batch of 160 images. The 640 you refer to was actually 640 'reviewed' images, meaning no images remained to be reviewed. We give the images reviewed information as it tells a newly logged -in reviewer that the telescope is indeed operating and gives an indication of the conditions (if the number of images is low for the UT time then the quality of the images is likely to be poor - making FMOs difficult to see.)

Q. Are your images of recent skies? Of successive nights?

A. All images available for review are less than 24 hours old. Ideally, FMOs need to be recovered within hours of discovery - their relative speed makes predicting future positions very uncertain. To ensure we have the best chance to recover any FMOs found by the public, images expire at 22 UT of the day the images were taken. We have improved the text on the 'Process Flow' discussion to answer this question more directly. Please see:

https://spacewatch.lpl.arizona.edu/fmo/process-flow

Q. Do all images have something in them that needs to be determined reportable or not reportable?

A. If you do not see an FMO, just click the 'Done' button on the review tool. The vast majority of images will have no trails worth submitting. FMOs are quite rare, being a public reviewer for this site requires a substantial amount of patience and perseverance.

Q. What is the typical JPEG image size?

A. The images are 1 MB in size and may be very slow to load over a modem.

Q. How many images does a reviewer have to inspect per night?

A. The FMO Project does not require specific time commitments. When images are available, they can be reviewed by anyone with a valid login.

Q. Is there any way to retract a candidate submission or resubmission?

A. NO method is offered for stopping a candidate once submitted. At the first submission level, errors are common and no one but the submitter will see the mistake so we do not consider this an issue. At the resubmission level your candidates go to observer, the resubmission page is straight forward so mistakes should not occur.

Q. I found a non-trailed moving object. Will you check if it is known asteroid?

A. The goal of our on-line project is to find asteroids that pass close to earth. Hence the interface deals strictly with the discovery of FMOs and does not offer tools to check non-trailing asteroids against our auto-detected objects or the MPC's archives.

Q. What happens when I submit a candidate from the review tool?

A. By clicking on the object of interest in the review tool you will receive a blinking snapshot of the three passes stacked (on the 'View submissions' page), allowing you to determine if the object is stationary (uninteresting). If the trail 'disappears' in the other two passes, you check a box indicating that you want the observer to review your candidate. Very few candidates should warrant resubmission to the observer - if someone submits too many false candidates we are forced to disable the forward feed for that user to avoid overloading the observer.

Q. Is it feasible that an FMO could appear in more than one pass of my blinking image for a candidate?

A. If a streak is a true FMO, it moves too fast to be in more than one picture of the stacked passes (blinking image). If you see a trail in more than one pass of the blinking image, it is not a FMO.

Q. Is it possible that very long streak on an image is a real FMO and not just a satellite?

A. A real FMO can be very fast and make a very long trail during our two minute exposures. These objects are called VFMOs and are practically impossible to recover. Our system is designed for the successful recovery of slower FMOs. VFMOs - while real - should not be submitted.

Q. When I find something, am I allowed to save it on my computer?

A. You may screen capture/download anything from our pages you wish, however the images are limited to your personal use unless you receive permission from SPACEWATCH®.

Q. What are NEAs?

A. NEA stands for "Near-Earth Asteroid". An asteroid is classified as a NEA if its orbit has certain characteristics (see the FAQ on NEA classes.) The characteristic common to all three classes of NEAs is that they all pass within 1.3 AU of the sun.

Q. What is a "close approach"?

A. A "close approach" is when an NEA passes within 0.2 AU of the Earth. Note that most NEAs (Near-Earth Asteroids) never make a close approach. Of the NEAs that do, they spend the vast majority of their time far, far away from the Earth - only periodically making their close approach. Reportable FMOs (Fast Moving Objects) are NEAs during their close approach - thus if you find an FMO and we confirm that it is reportable then you have contributed a measurement for an asteroid with a close approach to the Earth!

Q. What are PHAs?

A. PHA stands for "Potentially Hazardous Asteroid". PHAs are NEAs with minimum orbit intersection distances (closest approach between the asteroid's orbit and Earth's orbit) less than 0.05 AU and with absolute magnitude brighter than 22.0. That eliminates the really small objects (the ones that will vaporize in the Earth's atmosphere) and does not depend on the asteroid actually making such a close approach.

Q. What is an FMO versus a VFMO?

A. The term FMO was coined when a fast moving NEA was discovered in the old days of photographic discoveries. Fast referred to objects moving faster than local main belt asteroids and up to speeds of several degrees per day. On the long exposures (up to an hour in those days) even relatively slow objects left long trailed images, thus really fast objects would just be a line across the plate (no endpoints) - without endpoints, an object's speed could not be determined and therefore the orbit could not be parameterized for the purpose of followup.

Exposure times shortened substantially when CCDs replaced photographic plates (SPACEWATCH®'s exposure time is about 2 minutes.) These shorter exposure times meant shorter trails, hence the endpoints of a faster object trail became visible and thus measureable. SPACEWATCH® was the first program to use CCD technology for the discovery of asteroids. When SPACEWATCH® discovered its first long trailed object in its exposures, it was moving about 20 degrees per day (muchfaster than what could have been measured from a photographic plate) and we coined the term VFMO for Very Fast Moving Object. We use that term for objects moving faster than about 5 degrees per day (VFMOs are passing within 0.05 AU of the Earth!)

Q. What do you do when you find a VFMO?

A. Duck! Seriously, VFMOs are moving too fast for recovery attempts to have an acceptable chance for success. We do not bother to try recovering VFMOs.

Q. What does the mosaic observer do when given a possible FMO candidate?

A. The mosaic observer first determines if the candiate is a real FMO by searching for the object in pass 1 and pass 3. If the object is found in both, the three measurements are immediately mailed to the MPC and the object should appear on the CP for recovery by other telescopes. These discovery measurements will list you (the discovering FMO project reviewer) and the mosaic observer on the OBS line for proper MPEC credit should the object achieve a designation.

Q. What if the mosaic observer does not find the FMO in pass 1 or pass 3?

A. It is very possible your real FMO 1) moved off the CCD for pass 3 or 2) moved on the CCD during pass 2 so is not visible in pass 1. Either case gives us only two positions for the object (endpoints are averaged to one measurement to reduce error). If three measurements are NOT available, the MPC will not accept the FMO onto the CP as the uncertainty is too high - they cannot tell if the object's apparent motion is accelerating or decelerating. Thus, the mosaic observer attempts to find the object in an adjacent region to obtain a third measurement. If the SPACEWATCH® 1.8m telescope is still open and the object has not 'set' (dropped below the horizon) then the 1.8m observer is asked to make a recovery attempt. If a third measurement is not made, the FMO is considered lost and recovery efforts are dropped.

Q. When I review my submissions, I only see 'The [blinking] image of your candidate has not been produced yet. Please check again later.'

A. While the blinking images typically come down from Kitt Peak in under 10 minutes, the telescope may go into an emergency shutdown due to electrical storms. This, or the loss of the mountain network, can cause downloads to be delayed. Check the weather pages for possible causes.

Q. My candidate is not in the center of the image or in the pass two of the blinking image. Could you check the candidate again?

Q. I disagree with the observer analysis of my resubmission. What should I do?

A. We had a few responses to observer feedback mailings indicating disagreement with the observer's assessment. While we encourage emails when you feel the object is a real fmo and the observer did not fully review it (a situation that has yet to occur) we will not typically respond to disagreements on the classification of the false candidate. The observer feedback text is standardized - often candidates will not fit neatly into a predefined classification and the observer may 'punt' and respond with a common reply ('possibly caused by cosmic ray' is popular). The important point is that the candidate is, unfortunately, not real - the classification feedback is merely a training tool, not a forum to classify new anomalies.

Q. What are the purple circles shown in the jpegs?

A. The autodetection software places purple circles on (unverified) motion detections. The efficiency of the software is excellent so few real asteroids (unless they are FMOs) slip through undetected. The software can get confused around bright stars so not all purple circles are around real motions. See the Non-trailed asteroid FAQ for the ineventable followup question.

Q. Is there any way to access old images for other purposes? I'd be interested in working on algorithms for auto-detection.

A1. This question addresses two issues: First, use of autodetection algorithms

In the past, SPACEWATCH® did use autodetection algorithms for trails. As our images are noisy, these algorithms have a high false detection rate and we eventually abandoned them as our image production rates made the false detections untenable - it was found that visual inspection was more effective.With the introduction of the mosaic system, even visual inspection by the observer became unmanageable and the idea for the FMO Project was born. While you are welcome to collect images from our site for personal use in developing your own algorithms, SPACEWATCH® must grant permission for public uses.

A2. Second issue, availability of old images.

We do not offer old images for review. Namely, this public system is not designed for thorough analysis of each image - undoubtedly someone at some time will miss an FMO and subsequent reviewers may find it...too late for recovery. To save reviewers the frustration of finding something old or the embarrassment of a documented miss and to save ourselves the manpower drain from answering emails begging us to check a candidate from an archived image, we do not offer expired images through through the FMO Project. Images are offered for scientific studies through the SPACEWATCH® Archive Project.

Q. What is a geocentric (versus heliocentric) orbit?

A. A geocentric orbit is one which orbits the Earth (e.g. the Moon has a geocentric orbit.) The alternative is a heliocentric orbit, or an orbit around the sun. If the object has an orbit around the Earth, it is almost certainly a manmade spacecraft, and not worth further followup.

Q. What if I see the trail varying in brightness?

A. It used to be thought that rapid variation in brightness, for example along the trail during a 2.5 minute exposure, was a sure fire sign that you had a tumbling spacecraft rather than an asteroid. But recent observations of small asteroids has found that many of them are solid chunks of rock and have rotational periods as small as 1 minute! This variation does lead to recovery problems by making the trail endpoints less certain. Inaccurate endpoints leads to inaccurate measurements. Inaccurate measurements lead to bad orbital parameters and hence bad ephemerides - this is why three measurements on an FMO are necessary for the MPC to accept an object onto the CP.

Q. What are the different classes of NEAs?

A. NEAs are further classified into Apollo, Aten or Amor as defined by their orbital characteristics. For Apollo, a => 1.0 AU, q < 1.0 AU. Aten, a < 1.0 AU, Q > 1.0 AU. Amor, 1.0 AU < q <= 1.3 AU. a is the semi-major axis of the orbit (the mean distance to the sun), q is the perihelion distance (the closest point in its orbit to the sun) and Q is the aphelion distance (the farthest point in its orbit to the sun). By the above definitions, both Apollo and Aten asteroids actually cross the orbit of Earth (though not necessarily close to the Earth's actual path) while the Amors can come close to Earth, but their orbits do not actually cross the Earth's orbit.

Q. How often does an NEA make a close approach?

A. This is a difficult question and depends on the particular asteroid. All asteroids move, like all planets, according to Kepler's and Newton's laws and in regular motion around the sun. A close approach depends on the earth and the asteroid being in the same region of space at the same time. Sometimes the asteroid returns to the earth's orbit to find the earth somewhere else. Sometimes the earth is there. There are patterns in this interaction but they are not regular so it is hard to give a general frequency of close approaches.

That said, the most repeatable close approacher was (4179) Toutatis which was making close approaches to Earth every 4 years. It's orbital period is about 3.98 years so it was repeating it's encounter circumstances pretty closely at that interval, but those encounters slowly change until eventually it will avoid making any close approaches for awhile until the Earth and the object are in phase again sometime in the future. Other close approachers behave in a vastly different manner.

Q. I want to translate your site. Do I need permission?

A. We are thrilled when someone is interested in our project to the point they want to invest the time to translate our pages to another language so non-english communicators may participate. That said, please request permission to do so via email. By providing us a contact name and email we can notify you in the event of temporary closures, modifications and problems so you can pass the information along to your readers. Our only request is that you add to your mirror the following statement: "This website has been mirrored and translated with the permission of the SPACEWATCH® Project." Please respect that our pages and the images contained within are copyrighted and give the proper institutions and individuals credit.

Q. Why do I get the response 'stationary' when my object clearly disppears in one or more frames of the blinking image? Why do all the stars disappear in some blinking images?

A. When this occurs it means clouds were passing over the telescope. These conditions are not good for FMO recovery and to avoid frustration we strongly recommend that reviewers give up for the night when this occurs.

Extinction due to clouds

DISCLAIMER:
Many of the answers to these questions were generated by Anne Descour, a SPACEWATCH® Programmer with little knowledge of Astronomy (or grammar for that matter). She apologizes to the reader (and to SPACEWATCH®) for any inaccuracies - if we are notified of errors or mis-leading information it will be corrected promptly.