FLORA was the eighth asteroid discovered and was found by John Russell Hind from Regent’s Park in London on the evening of 18th October 1847. This was Hind’s second asteroidal discovery for 1847, after finding the previous minor planet 7 Iris two months beforehand. Hind found Flora using a visual chart in which the position matched no known star. Shining at 9th magnitude in Leo, Flora revealed some motion on the same night, confirming that it was a new minor planet. As Hind (1847) says; “…I had no hesitation in deciding of its nature.”. Within weeks the brightness continued to climb until the minor planet reached its maximum of around 8th magnitude.
FLORA DATADiscoverer : J. R. Hind Date : 18th October 1847 Satellites : 0 Diameter : 145×145×120 km. Polar Tilt : ° ? Period (P) : 3.27 years Synodic Period : 475.7 days Orbital Velocity : 20.0 km.s-1 Perihelion (q) : 1.86 A.U. Aphelion (Q) : 2.55 A.U. Eccentricity (e) : 0.1561 Inclination (i) : 5.887° Mass : c. 3.8×1018 kg. Mean Density : c. 2.7 g.cm-3 Mean Distance : 2.02 AU or 3.291 ×108 km Sidereal Rotation : 12.9 hr. Mean Sidereal Rotation : 0.5363 d. Maximum Diameter : 0.21 ″ (arcsec) Minimum Diameter : 0.05 ″ (arcsec) Maximum Magnitude : 7.9 Minimum Magnitude : 11.5 |
Amazingly within six short weeks, Hind had sufficient information to declare some early orbital elements for Flora, which he published in August“s RAS Monthly Notices of 1847. Flora was a surprise in several ways, At the time it was found as the closest asteroid orbit to the Sun. He realised Iris was significantly influenced by the gravitational field of Vesta, Ceres and Pallas, producing perturbation, and furthermore, that the inclinations were very similar to Astraea and Iris. Hind (1847a) also provided an ephemeris, which would be useful when Flora emerged from conjunction in 1848 - a remarkable achievement for the day. When recovered in 1848, several observers were too publish updated orbital elements, and by the end of 1848, Hind produce his third computation of the orbit.
In the annual “Report to the Twenty-eigth Annual General Meeeting”, MNRAS., 8, pg. 82 (1848) a summary of the discovery and the speed of the calculation of the orbital element. The report says;
“On the night of October 18th, another small planet was detected by Mr. Hind, at Mr. Bishop’s Observatory, near the star Bessel v.48, of Weisse’s Catalogue, with which it was comipared. At the time of discovery it was not very far from its stationary point. During the month of November it equalled in brightness stars of the 8th magnitude, but at present it is a little below the 9th. The elements of this planet, which has received the name of Flora on Sir John Herschel’s proposition, have already been determined with a considerable degree of accuracy. There appears to be no instance on record where the orbits of various astronomers for a planetary periodical comet have agreed so well together : the values of the mean daily motion in the several orbit, do not differ more than 7′ or 3′, and the other elements are very accordant. The period of revolution of Flora is shorter than that of any other of her companion planets. The symbol adopted for her designation is the figure of a flower. Observations of the planet will be practicable for some months longer, and an ephemeris, extending to May 1, is given in the last number of our Monthly Notices.
By 1849, many measures of positions were achieved, and much work was undertaken to understand the effects of perturbations from the other minor planets and for Jupiter and Saturm - hopefully discover the how this changed the various planetary predicted orbits. One of first was by Dr. F. Brünnow from Berlin Observatory in April 1853, which was comunicated by Professor Encke to the Astronomer Royal for publication in the RAS Monthly Notices.
In the years to follow, various attempts were made to refine the calcuations and the influence of the perturbations. Johann Franz Encke (1791-1865) was a brillant and masterful mathematican, who applied his genius to problems of planetary and asteroidal orbits, and the subtle effects on gravitational inflence from each others. He became a professor of astronomy in 1844, and was well respected throughout Europe and in England. His main fame was his substaintial work with the periodic comet known as Encke’s, but this in fact was only the beginning of his influence. For example, in 1837 his careful observations of Saturn and its rings, describing for the for the first time Encke’s Division.
One of the important investigations, that took much of his time later in his career. Starting in 1830’s, he began working on orbital analysis of other comets than Encke’s Comet, which expanded to metoer showers and the newer asteroids being discovered. The discovery of 8 Flora was the really important step on reinforcing his new perturbation theory. This view was in retrospect the validation or continuation of working out a method of calculating an elliptical orbit from three observations - a method that is still used today. By 1851, Encke had worked out how to express planetary perturbations using rectangular co-ordinates - allowing the addition of these small changes to more accurately calculate ephemerides - especially for the outher planets and the ever expanding numbers of newly discovered asteroids.
Later in 1875, the comet observer, Johann Gottfried Galle (1812-1910), at the time placed in Breslau in Germany became the first to use the Flora to measure the solar distance. This was obtained by finding the value of the solar parallax, calculating the astronomical unit (AU) as being 148.290 million kilometers.
Flora has the notoriety of being the closest of the significantly large asteroids, whose original name was assigned by the highly notable 19th Century English observer, Sir John Herschel, who was to even assigned the flowery symbol of the rose to it! This minor planet can only be seen, even during opposition, with some form of optical aid, and will rarely rise just above 8th magnitude. Lying at the mean distance of 2.02 AU, and with an orbital period of 3.27 years, this potato-shaped asteroid averages about 135 km. in diameter. Most of the time the orbit remains close to the ecliptic, though the inclination of 5½° - notably very similar to the Moon - means Flora can range between ±31° in declination. Observations of its light shows slight fluctuations in brightness, and this suggests the 12h 54m rotation. Its own composition seems likely to be an aggregate of rubble-like material that is mainly rich in nickel, iron and silicates.
Flora is named after the Roman goddess (Greek Nymph goddess Chloris 2 or Khloris) of the gardens and specifically flowers. She is the lovely and joyous daughter of Spring, sometimes the Seasons, being the Greek goddess, Persephone 1 or Kora, whose Roman equivalent is Proserpina (Persipina) or Libera.
Flora was to marry Zephyros, the god of the West Wind and the bringer of spring rains to cultivate the earth, after she being earlier kidnapped by him. Her own child to be born was Carpos or Karpos; the Greek goddess of Fruit. Flora is always portrayed as a dainty and delicate child, whose kind love and rose perfumed breath nurtures the flowers and causes them to be colourful, to bloom and eventually propagate - a trait probably inherited from her own mother.
Chloris is more often associate with the Greek word khloros mean green to pale green. Hence we see the association with the greens of leaves trees and plants. Still this analogy of here also seems a little odd, as chloris has the associated word with the greenish 17th chemical element, Chlorine, which is actually a deadly gas. Yet chlorine is associated with the chemical compound of salt - sodium chloride, a much needed substance of life on earth! Here like most of the Greek gods and goddesses, even the most kindest, beautiful and highly elegant of them always seems to have some dark or dopplegänger (evil twin) side. Mostly their natures reaps good, but they can dish out their own wrath through inflicting punishment and suffering to those those mortals they deem unworthy or deserving.
Flora own mythology is also embellished in the folklore of many different cultures. She is certainly related to the benign and good-natured fairies and the elves (the Welsh ellyllon whose magical stories are often adored and imagined in childhood by very young girls. Adoption also has come from the Celts and the Norse, where these imaginary creatures are considered minor divine sprits among the natural world - and parallel to the similar legends of the water nymphs (See Neptune Mythology) or the satyers, etc.
Endnotes :
1. Persephone (399) is the main belt minor planet discovered by Max Wolf on 23rd February 1895 from Heidelberg in Germany. Its diameter is 41.9 km., whose mean orbital period is 5.34 years at the mean distance of 3.057 AU.
2. Chloris (410) is
another main belt minor planet discovered by Auguste
Charlois on 7th January 1896 from Nice. Chloris is
surprisingly large, having the mean diameter is 124 km.,
and one would expect such an object to be brighter than it
appears telescopically. No doubt this C-type object has a
low albedo, which is likely composed of various
carbonaceous substances. Chloris has the mean orbital
period is 4.51 years at the mean distance of 2.729 AU. The
orbit is fairly eccentric and is inclined by
10.9° to the ecliptical plane.
This minor planet Chloris was notable in
2008, as it was predicted to occultate an 8.7 magnitude
star, HIP 21953 in Taurus on the 12th March. Eclipse
duration was expected to last about 5.5 seconds, whose drop
in brightness was predicted to be 5.9 magnitudes at
minimum. The 155 kilometre wide path crossed much of the
Indian Ocean but should have been visible, even though it
was merely 10° from the horizon, from the top
half of the Northern Territory in Australia. At the time of
writing, no observations had been recieved of this event,
likely because of the general placement of the path.
Another event occurred on the 9th April 2008, which was
visible from western Africa, occultating an 12th magnitude
star.
Yet a third event is predicted for 07th February 2009,
where 12.7 magnitude Chloris will occultate a 9.7 magnitude
star for about 8.3 seconds or so. The path is expected to
travel through northern India, Bangladesh, northern Vietnam
and on to the Philippines, before travelling across the
mid-western Pacific Ocean. (See
Chloris Occultation)
References:
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0h UT (J2000) Mag Δ r El. Con
DATE R.A. Decl. V A.U. A.U. o
hh mm.m o ′
*********************************************************
-- 2007 --
29 Dec 03 19.0 +11 39 08.8 1.092 1.906 133 Ari
-- 2008 --
12 Jan 03 22.8 +13 19 09.2 1.225 1.922 121 Ari
26 Jan 03 33.2 +15 11 09.5 1.377 1.940 109 Tau
09 Feb 03 48.9 +17 06 09.8 1.541 1.959 099 Tau
23 Feb 04 08.9 +18 56 10.1 1.712 1.980 090 Tau
08 Mar 04 32.1 +20 34 10.3 1.886 2.002 082 Tau
22 Mar 04 57.9 +21 56 10.5 2.060 2.026 074 Tau
05 Apr 05 25.6 +22 59 10.7 2.230 2.050 067 Tau
19 Apr 05 54.5 +23 39 10.8 2.394 2.075 060 Tau
03 May 06 24.4 +23 55 10.9 2.551 2.100 053 Gem
17 May 06 54.6 +23 47 11.0 2.697 2.126 046 Gem
31 May 07 24.9 +23 15 11.0 2.832 2.151 040 Gem
14 Jun 07 55.0 +22 20 11.1 2.954 2.177 033 Gem
28 Jun 08 24.6 +21 06 11.1 3.060 2.202 027 Cnc
12 Jul 08 53.5 +19 33 11.1 3.151 2.228 021 Cnc
26 Jul 09 21.8 +17 46 11.1 3.223 2.252 014 Cnc
09 Aug 09 49.3 +15 45 11.0 3.277 2.277 008 Leo
23 Aug 10 16.0 +13 36 10.9 3.310 2.300 003 Leo
06 Sep 10 42.0 +11 20 11.0 3.322 2.323 007 Leo
20 Sep 11 07.2 +09 00 11.2 3.311 2.345 013 Leo
04 Oct 11 31.8 +06 40 11.3 3.278 2.367 020 Leo
18 Oct 11 55.7 +04 21 11.4 3.223 2.387 028 Vir
01 Nov 12 18.9 +02 08 11.4 3.144 2.406 036 Vir
15 Nov 12 41.2 +00 04 11.4 3.043 2.424 044 Vir
29 Nov 13 02.7 -01 49 11.4 2.921 2.441 052 Vir
13 Dec 13 22.9 -03 29 11.4 2.781 2.457 061 Vir
27 Dec 13 41.6 -04 52 11.3 2.625 2.472 070 Vir
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Poorly placed in the sky after about March
2008 as it approaches solar conjunction 21st August.
Starting 16 April Flora crosses from Taurus to Gemini. Then
on 2nd May will passes 1.4°N of 3.0 mag. Mu Gem
/ 27 Gem when at just above 11th magnitude, and then on 13
May will be 1.2°S of 2.9 mag. Epsilon Gem / 13
Gem / Mebsute. The 17th May finds Flora at 11.0 magnitude.
By late-June Flora approach its conjuction with the Sun,
making the minor planet difficult to observe. Early risers
from about late-October will be able to easily
located Flora again. Prior to this date, the minor planet
crosses from Leo into Virgo (7th August).
On 16th November, 11.6 magnitude Flora will be
1.4°S from the close binary star, 2.7v magnitude
star Gamma Viginus/ 29 Vir / Porrima, at an elongation of
45°. Flora then continues to crawl through Virgo
into 2009, when it will reach its next anticipated
opposition on 19 April 2009.
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0h UT (J2000) Mag Δ r El. Con
DATE R.A. Decl. V A.U. A.U. o
hh mm.m o ′
*********************************************************
10 Jan 13 58.4 -05 56 11.2 2.456 2.485 080 Vir
24 Jan 14 12.5 -06 37 11.1 2.281 2.497 091 Vir
07 Feb 14 23.2 -06 52 10.9 2.105 2.508 102 Vir
21 Feb 14 29.6 -06 42 10.7 1.936 2.518 115 Vir
07 Mar 14 30.9 -06 03 10.4 1.785 2.526 129 Vir
21 Mar 14 26.6 -05 01 10.1 1.662 2.533 143 Vir
04 Apr 14 17.0 -03 41 09.8 1.580 2.538 159 Vir
18 Apr 14 03.8 -02 20 09.6 1.547 2.542 170 Vir
02 May 13 49.9 -01 15 09.8 1.568 2.545 162 Vir
16 May 13 38.2 -00 41 10.1 1.639 2.546 147 Vir
30 May 13 30.9 -00 42 10.4 1.752 2.546 132 Vir
13 Jun 13 28.7 -01 19 10.6 1.895 2.544 119 Vir
27 Jun 13 31.4 -02 23 10.8 2.057 2.541 107 Vir
11 Jul 13 38.4 -03 49 11.0 2.229 2.537 095 Vir
25 Jul 13 49.1 -05 29 11.2 2.404 2.531 085 Vir
08 Aug 14 02.8 -07 20 11.3 2.574 2.524 076 Vir
22 Aug 14 19.0 -09 16 11.4 2.737 2.515 067 Vir
05 Sep 14 37.4 -11 13 11.5 2.886 2.505 058 Lib
19 Sep 14 57.6 -13 09 11.5 3.021 2.494 050 Lib
03 Oct 15 19.6 -15 00 11.5 3.137 2.482 042 Lib
17 Oct 15 43.1 -16 42 11.5 3.233 2.468 034 Lib
31 Oct 16 07.9 -18 14 11.4 3.306 2.453 026 Sco
14 Nov 16 34.0 -19 33 11.4 3.356 2.437 018 Oph
28 Nov 17 01.1 -20 35 11.2 3.382 2.420 011 Oph
12 Dec 17 29.0 -21 20 11.1 3.383 2.401 003 Oph
26 Dec 17 57.6 -21 46 11.1 3.360 2.382 005 Sgr
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Flora is best observed between February and
July during 2009. Opposition will occur on 19th April in
Virgo at 9.6 magnitude, and will be the seconded brightest
asteroid just one whole magnitude behind 8.9 magnitude
asteroid (14) Irene, and just 0.2 ahead of asteroid (8)
Hebe.
At the beginning of the year until September, Flora will
remain in eastern portion of Virgo, ENE to NE of the 1st
magnitude star Spica (α Virginus.) On 28th January,
11th magnitude Flora will lie some 41′ S of 4.1v
magnitude Symra / Iota (&iota) Vir / 99 Vir. After January
has been completed, Flora begins its northward curved loop,
in retrograde motion, as the earth catches up, then
overtakes the minor planet. Watch out for 10.8 magnitude
Flora on 18th February as it passes 5.2′ from orange
5.4 mag. 106 Vir. The 4th March finds the stationary point,
where the motion changes from direct to retrograde, where
Flora marches towards the NE. After opposition on the
19th April, a close approach by Flora will happen on 27th
April (4h UT; 12pm AEST) when it lies 5.1′S from the
5.2 magnitude star, 90 Aqr. This is followed on the 29th,
when it will be roughly 20′N of 12th magnitude spiral
galaxy, NGC 5334.
However, on 22nd May the best close approach of 2009 will
be with 3.4v magnitude Zeta (ζ) Virginus in the early
evening in Australia, when 10.3 magnitude Flora will pass
merely 115 arcsec or 1.9′ to the South. This will
make a wide optical pair, which will make it easy to locate
Flora for any first timer seeking this minor planetary
body.
By June, the magnitude drops again below 10th, reaching
the end of the retrograde motion to resume its direct
motion. In July the magnitude drops below 11th, and Flora
again moved towards Symra / Iota Vir that it passed in
late-January. On 16th August, at 11.4 mag, Flora will be
2.6° SSW of Symra, followed on 24th when it
moves out of Virgo and into Libra. From October, Flora
moves towards its unobservable southern hemisphere
conjunction on the 18th December, becoming simply
impossible to see after the beginning of November and the
next four months or so. The next more favourable opposition
will happen in Aquarius during September 2010, when Flora
rises to about 8.0 magnitude for the first time since 2007,
and will not be as bright again until mid-2013.
*********************************************************
0h UT (J2000) Mag Δ r El. Con
DATE R.A. Decl. V A.U. A.U. o
hh mm.m o ′
*********************************************************
09 Jan 18 26.5 -21 51 11.2 3.312 2.361 012 Sgr
23 Jan 18 55.6 -21 37 11.2 3.241 2.340 020 Sgr
06 Feb 19 24.5 -21 03 11.2 3.149 2.317 027 Sgr
20 Feb 19 53.1 -20 12 11.2 3.037 2.294 035 Sgr
06 Mar 20 21.1 -19 05 11.2 2.907 2.270 042 Cap
20 Mar 20 48.4 -17 44 11.1 2.762 2.246 049 Cap
03 Apr 21 14.8 -16 14 11.1 2.604 2.221 057 Cap
17 Apr 21 40.2 -14 39 10.9 2.437 2.195 064 Cap
01 May 22 04.4 -13 01 10.8 2.262 2.170 072 Aqr
15 May 22 27.3 -11 27 10.6 2.082 2.144 080 Aqr
29 May 22 48.5 -10 01 10.4 1.902 2.118 088 Aqr
12 Jun 23 07.8 -08 50 10.2 1.723 2.093 096 Aqr
26 Jun 23 24.4 -08 02 09.9 1.550 2.068 105 Aqr
10 Jul 23 37.7 -07 44 09.6 1.386 2.043 116 Aqr
24 Jul 23 46.6 -08 03 09.3 1.238 2.019 127 Aqr
07 Aug 23 50.0 -09 07 08.9 1.112 1.996 140 Aqr
21 Aug 23 47.2 -10 51 08.5 1.016 1.974 154 Aqr
04 Sep 23 38.7 -13 00 08.1 0.957 1.953 167 Aqr
18 Sep 23 26.7 -15 01 08.1 0.943 1.934 167 Aqr
02 Oct 23 15.5 -16 18 08.4 0.971 1.917 153 Aqr
16 Oct 23 09.0 -16 35 08.7 1.037 1.901 138 Aqr
30 Oct 23 09.1 -15 51 09.0 1.132 1.888 125 Aqr
13 Nov 23 15.8 -14 18 09.3 1.247 1.877 114 Aqr
27 Nov 23 28.3 -12 07 09.5 1.374 1.868 103 Aqr
11 Dec 23 45.3 -09 29 09.7 1.510 1.861 094 Aqr
25 Dec 00 05.7 -06 30 09.9 1.649 1.858 086 Cet
*********************************************************
*********************************************************
0h UT (J2000) Mag Δ r El. Con
DATE R.A. Decl. V A.U. A.U. o
hh mm.m o ′
*********************************************************
08 Jan 00 28.6 -03 18 10.1 1.790 1.857 078 Cet
22 Jan 00 53.6 +00 01 10.2 1.929 1.858 071 Cet
05 Feb 01 20.3 +03 23 10.3 2.065 1.862 064 Psc
19 Feb 01 48.4 +06 41 10.4 2.197 1.869 058 Psc
05 Mar 02 17.7 +09 51 10.5 2.324 1.878 052 Cet
19 Mar 02 48.2 +12 48 10.6 2.445 1.890 046 Ari
02 Apr 03 19.7 +15 27 10.6 2.558 1.903 040 Ari
16 Apr 03 52.2 +17 45 10.6 2.663 1.919 034 Tau
30 Apr 04 25.5 +19 39 10.7 2.758 1.937 029 Tau
14 May 04 59.3 +21 05 10.7 2.844 1.956 023 Tau
28 May 05 33.5 +22 03 10.7 2.918 1.977 018 Tau
11 Jun 06 07.6 +22 32 10.6 2.980 1.999 012 Gem
25 Jun 06 41.4 +22 32 10.6 3.028 2.022 007 Gem
09 Jul 07 14.7 +22 06 10.4 3.063 2.046 001 Gem
23 Jul 07 47.2 +21 15 10.6 3.081 2.071 005 Gem
06 Aug 08 18.7 +20 04 10.8 3.084 2.096 011 Cnc
20 Aug 08 49.0 +18 34 10.9 3.069 2.122 017 Cnc
03 Sep 09 18.2 +16 51 11.0 3.037 2.147 023 Cnc
17 Sep 09 46.1 +14 57 11.1 2.986 2.173 030 Leo
15 Oct 10 37.9 +10 58 11.1 2.827 2.224 044 Leo
29 Oct 11 01.8 +09 00 11.1 2.720 2.249 052 Leo
12 Nov 11 24.0 +07 09 11.1 2.597 2.273 060 Leo
26 Nov 11 44.5 +05 30 11.0 2.458 2.297 069 Vir
10 Dec 12 02.8 +04 08 11.0 2.307 2.320 078 Vir
24 Dec 12 18.4 +03 08 10.8 2.149 2.342 089 Vir
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*********************************************************
0h UT (J2000) Mag Δ r El. Con
DATE R.A. Decl. V A.U. A.U. o
hh mm.m o ′
*********************************************************
07 Jan 12 30.7 +02 36 10.7 1.988 2.363 100 Vir
21 Jan 12 38.7 +02 36 10.5 1.832 2.384 112 Vir
04 Feb 12 41.7 +03 14 10.2 1.690 2.403 126 Vir
18 Feb 12 38.9 +04 28 10.0 1.574 2.421 141 Vir
03 Mar 12 30.5 +06 10 09.7 1.497 2.439 156 Vir
17 Mar 12 18.0 +08 02 09.4 1.469 2.455 170 Vir
31 Mar 12 04.3 +09 37 09.6 1.494 2.469 164 Vir
14 Apr 11 52.6 +10 37 09.9 1.571 2.483 149 Leo
28 Apr 11 45.1 +10 53 10.2 1.691 2.495 134 Leo
12 May 11 43.0 +10 29 10.5 1.842 2.506 120 Leo
26 May 11 45.8 +09 31 10.8 2.014 2.516 108 Vir
09 Jun 11 52.9 +08 08 11.0 2.196 2.524 097 Vir
23 Jun 12 03.4 +06 26 11.2 2.382 2.531 086 Vir
07 Jul 12 16.7 +04 31 11.3 2.565 2.537 077 Vir
21 Jul 12 32.1 +02 25 11.4 2.740 2.541 068 Vir
04 Aug 12 49.3 +00 12 11.5 2.904 2.544 060 Vir
18 Aug 13 07.9 -02 03 11.6 3.053 2.546 051 Vir
01 Sep 13 27.7 -04 21 11.6 3.184 2.546 043 Vir
15 Sep 13 48.6 -06 37 11.6 3.296 2.544 035 Vir
29 Sep 14 10.6 -08 50 11.6 3.386 2.542 028 Vir
13 Oct 14 33.4 -10 58 11.5 3.452 2.537 020 Lib
27 Oct 14 57.1 -12 57 11.4 3.494 2.532 012 Lib
10 Nov 15 21.6 -14 46 11.3 3.509 2.525 005 Lib
24 Nov 15 46.7 -16 23 11.3 3.499 2.517 005 Lib
08 Dec 16 12.3 -17 45 11.4 3.462 2.507 012 Sco
22 Dec 16 38.4 -18 52 11.4 3.399 2.496 020 Oph
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************************ Opposition Conjunction ************************ 05 Aug 2006 26 May 2007 *************************
The user applying this data for any purpose forgoes any liability against the author. None of the information should be used for either legal or medical purposes. Although the data is accurate as possible some errors might be present. The onus of its use is place solely with the user.
