Kepler Recovers After 144 Hour "Glitch" 73
coondoggie writes "There was likely a pretty big sigh of relief at NASA's Ames Research Center this week as the group's star satellite Kepler recovered from a glitch that took it offline for 144 hours. According to NASA the glitch happened March 14, right after the spacecraft issued a network interface card (NIC) reset command to implement a computer program update. During the reset, the NIC sent invalid reaction wheel data to the flight software, which caused the spacecraft to enter safe mode, NASA stated."
Auto-Restore (Score:4, Interesting)
If it had gone into safe mode for more than ## Days does it have a "return to factory defaults" subroutine?
Re:Was it really down? (Score:4, Interesting)
"Down/offline", meaning not performing the science mission, NOT, unreachable with no telemetry.
BIG PROBLEM???!!! (Score:4, Interesting)
Any Kepler scientists/engineers/technicians out there?
As some of us lay people know, Kepler "works" by "staring" at a single, small region of the sky for a very long (years!) period of time. If there is any dimming of the 100,000+ stars in the monitored region during this time, this is considered a possible transit by an extra-solar planet. If there are two of these transits around the same star, some rough orbital characteristics can be mapped out. A third, evenly spaced transit around the same star is considered confirmation of a new extra-solar planet! (The magnitude and other characteristics of the transits can provide other useful information such as size, possible moons etc.)
So what happens if Kepler has a 144 hour "gap" in its observations because it wasn't looking at this region for that duration? (Going into safe mode requires re-orienting the spacecraft so that the solar cells get maximum power, also there may have been some issues with the reaction wheels which point the spacecraft). I'm sure their are some very smart people programming some very powerful computers to try to minimize that impact of the loss of data but I'm curious, how will this show up? Will it mean that there is a range of orbits that won't be confirmed without a fourth transit? Will this range be large? Will it be in the "habitable zone" around G type (our sun) stars?
Also, I'm assuming that because the spacecraft does periodic "quarter turns" that it is designed to re-align itself (perfectly?) with the target region. In that case (I hope) I'm curious; does it matter what pixels in the imager are receiving a particular star? Are they all calibrated the same or, if the star-light falls upon more than one or on a pixel boundary, can the software make adjustments so that the measurements will provide consistent data? (Then again maybe consistency isn't needed, all they're looking for are short term changes on the scale of hours right?)
Please (God? NASA?) let this problem not cause any big problems. Kepler is the closest thing we've got to an "earth finder"! (And in quantity!).