Rosetta Comet chaser closing in- *** GLP has discovered a new asteroid - New picture page 7, no name yet, share your thoughts ***

This is a directory that is described as the orbit kernels in SPICE for the Rosetta mission.

ftp://ssols01.esac.esa.int/pub/data/SPICE/ROSETTA/kernels/spk​/

Which I guess you can read with the SPICE utilities

[link to naif.jpl.nasa.gov]

Do you have any experience of using SPICE ?

Very cool science!

That's what I mean, I have 0 experience with SPICE utilities, no idea how to generate an ephemeris from it. I could compile the source code for the utilities and figure it out eventually, but by then the photo itself will be ancient history given the "speed of the internet." Even then, I can only hope the kernels are fine grained enough to account for all the individual maneuvers in the cruise phase and test maneuvers. I assume they would.

Well done Astro )

Unfortunately I also have to prepare for the Camelopardalis meteor shower webcast tomorrow night, and I was going to make an announcement video about that tonight, so I really don't have ample amounts of time to fool around with SPICE utilities. I will work on a better version of the images for comparison, both to the image taken today and to the Palomar plate.

OK I will have a little look at it, although I can't promise anything. I already have two pieces of software called SPICE running on this PC ( virtualisation and circuit simulator ) what could possible go wrong ;).

I have the SPICE utilities running here and have managed to convert some of these orbit kernels to transfer format. They have some plain text ephemeris like this


JPL On-Line Ephemerides Horizons
*************************************************************​******************

Target body : NEAT {source: Horizons-SPK:JPL#106}
Target SPK ID : 1000351
Coord center : Sun ( 10) {source: SB405-CPV-2}
GM of center : 2.9591220828559109E-04 AU^3/D^2
Small perturbers: Ceres, Pallas, Vesta {source: SB405-CPV-2}
Small body GMs : 6.32E+01, 1.43E+01, 1.78E+01 km^3/s^2
Requested by : [email protected]
Execution date : Thu Apr 22 14:04:58 2004 (Pasadena time)
Start time : 2004-Jan-01 00:00:00.0000 CT
Stop time : 2004-Oct-01 00:00:00.0000 CT
Step (days) : 0.1250
*************************************************************​******************
Initial FK5/J2000.0 helio. ecliptic osc. elements (AU, DAYS, DEG):
EPOCH= 2453121.5 != 2004-Apr-26.0000000 (CT) Residual RMS= .55462
EC= 1.000469799683324 QR= .9619490939801648 TP= 2453141.470210163
OM= 210.2787016944886 W= 1.208915547744374 IN= 99.64241749931878
Comet physical & dynamic parameters (KM, SEC; A1,A2,A3=AU/d^2; DT=days):
GM= n.a. RAD= n.a. A1= 4.330337E-8
A2= -2.633445E-8 A3= n.a. DT= n.a.
M1= 5. M2= n.a. k1= 7.5
k2= n.a. PHCOF= n.a.

++++++++++++++++++++++++++++++++++++++++++++++++++++++++
A-posteriori SPK fidelity estimate (rel. to integrator):
Max. error (3 std. dev) Time
------------------------ ------------------------
X: 0.8091423118872746D-04 m 2004-Mar-05 03:00:00.000
Y: 0.2163408294939110D-04 m 2004-Aug-28 03:00:00.000
Z: 0.8191053093430347D-04 m 2004-Sep-29 03:00:00.000
RSS: 0.1171515319228198D-03 m 2004-Sep-29 03:00:00.000
++++++++++++++++++++++++++++++++++++++++++++++++++++++++

in them, any use to you ? ( they are all for different bodies etc )

K

That one isn't useful, the orbital elements are ancient. The epoch would have to be yesterday, about 2456799.5 JD.

Also just realized the target body is "NEAT," I assume that refers to one of the NEAT comets, not the Rosetta probe itself. Eccentricity > 1 seems to support this.

Last Edited by Astromut on 05/22/2014 05:42 PM

Awesome! Congratulations!

The kernel to calculate Rosetta's position in the current time frame is RORB_DV_006_01_______00014.BSP


Objects
--------------------------------------------------------

This file contains ROSETTA (-226) position.
NAIF ID code for ROSETTA is -226.


Approximate Time Coverage
--------------------------------------------------------

This file covers the following time span:

Start of Interval End of Interval
-------------------------------- --------------------------------
JAN 01,2014 00:00:00.0000 (TDB) AUG 03,2014 09:01:07.1832 (TDB)

I have no idea if I can get any useful information from it. I will have a look tomorrow ( my tomorrow )

K

OK am I on the right track here?

State Vector Results


Calculation Inputs

Calculation type = State Vector
Target = ROSETTA ORBITER
Observer = EARTH
Reference frame = J2000
Light propagation = No correction
Time system = UTC
Time format = Calendar date and time
Input time = 2014 MAY 21 14:30:00.000
State representation = Right ascension, declination, range


State Vector Results

UTC calendar date Right Ascension (deg) Declination (deg) Range (km) d Right Ascension/dt (deg/s) d Declination/dt (deg/s) d Range/dt (km/s) Speed (km/s) Time at Target Light Time (s)
2014-05-21 14:30:00.000000 UTC 298.00489435 -27.82604628 498397703.44037000 -5.86569401E-07 -4.90607971E-07 -29.68355762 30.32635802 2014-05-21 14:30:00.000000 UTC 1662.47578997


Kernels Used

pds/data/ros-e_m_a_c-spice-6-v1.0/rossp_1000/EXTRAS/MK/ROS_V0​3.TM

K

Yeah but can these probes cure world hunger, poverty, sickness or enslavement? What's that you say, they can't? Oh, then just another million/billion dollars wasted to please the "minds" of a few scientist. I'm sorry, but space exploration does nothing when you're pumping billions of tax payer dollars into "research", when you can't even explore the basic needs of humanity and meet them with swiftness and honesty. Or, in short:

People are still starving. Projects like this are the reason.

Yeah, I think you're on the right track, though the observation time was about 17:30 UT, not 14:30. Also, it needs to correct for light propagation. I'll also have to convert to topocentric coordinates.

:hestonwtf:
No, projects like this are not the reason. Projects like this are a miniscule portion of the budget. Projects like this inspire young minds to pursue careers in science and engineering, which ultimately keeps them out of poverty and encourages the furthering of science and technology in ways that could not be anticipated.

Last Edited by Astromut on 05/22/2014 06:57 PM

Here's the image, compared between yesterday's image with Rosetta present to today's image without Rosetta, and then to the corresponding POSS plate which also lacks Rosetta.
[link to h.dropcanvas.com]

You are narrow minded. The answer is yes. These probes can cure world hunger, poverty, sickness, and enslavement. That is what science does. We learn things by exploring our reality. Projects like this are not the reason people are starving. You and people who think like you are the reason people are starving. You have no vision. If no money was invested in science, you would not be able to post on GLP. There would be no such thing as the internet or human use of electricity.

Hey, Astro -- someone gave me red karma because they believe I'm you. I'll wear it, proudly.

Guess I don't understand how GLP has "set a new world record" saw no publicity... just saying.

:withstupid:

Stars are so beautiful. Congratulations on finding something in the space between.

Hope you are recognized beyond the forum.

Dr. Dude, you are the Daryl Dixon of astronomers. Truly cool

Good morning Dr Astro

As far as I can see you can do SPICE geometry calculations through a web interface here

[link to wgc.jpl.nasa.gov:8080]

choose the state vector calculation. JPL have a Rosetta kernel, but I don't know if it is out of date or indeed if that makes much difference. I will carry on looking at the ESA Rosetta kernels when I can but I am pretty busy today. Good luck, I hope you get a good match.

K

Very nice. You know this is going to lead to your name being published, right?

There is another big burn planned for the 4th June, another chance to image maybe?

Here is information about the big burn and what happens next.



[link to www.youtube.com]

K

Dr. A, maybe you can answer. Why did they block out what would have been a stunning image of Saturn in the image on page 3? (earth as seen from Saturn - Cassini)

It's actually in shadow. When Cassini is in Saturn's shadow they can image fainter objects like the fine ring structure and in this case the Earth.

[link to www.nasa.gov]

K

Gotcha. Looked like they just took the ellipse tool in PS and drew on a void. You're like a motherfuckin' Google for space shit. Thanks.

Yeah, I'd rather get the info straight from the ESA since it's their probe. I'm talking to some JPL people now though, the data has some people excited behind the scenes. If it's confirmed it's a first.

God I hope not. Wouldn't be the first time, last time was quite by surprise.