Transcript PARTICIPATION IN ISON PROJECT: OBSERVATIONS OF …

PARTICIPATION IN ISON PROJECT:
OBSERVATIONS OF NEAR-EARTH
ASTEROIDS AND GRB AFTERGLOWS
Yurij Krugly
Outreach seminar
in margins of
55th session of Committee on the Peaceful Uses of Outer Space
11 June 2012
Institute of Astronomy of
Karazin Kharkiv National University
UKRAINE
1804: Kharkiv University was found
1808: The astronomy courses were started
1908: The planetary and Moon studies were started
1978: Study of asteroids was started
1995: CCD observations of asteroids were initiated
2006: Cooperation with the ISON project was started
ISON - Scientific Optical Network
The ISON project goals:
• Enhancing international collaboration in optical observations of celestial
objects between observatories in developing nations and scientific
organizations in industrialized countries
• Support of existing and establishing new telescope facilities in developing
countries
• Development and implementation of new observation technologies using
modern equipment and software tools
• Education and training
The ISON project scientific tasks:
• Studying man-made space debris
• Discovery and tracking of near-Earth asteroids (NEAs) to improve orbital
parameters and to study their physical properties
• GRB optical afterglow observations
Cooperation with ISON
Since 2006 Kharkiv Asteroids and Comets Group cooperates with ISON in
photometry of asteroids.
Since 2009 Kharkiv Asteroids and Comets Group coordinates asteroid
photometry observations within the framework of ISON.
Several ISON instruments are involved into this work coordinated from Kharkiv.
Several meetings and mutual visits were organized in the framework of ISON
cooperation in order
- to establish photometric observations
- to train observers
- to discuss problems of photometry and discovery of asteroids
- to improve image processing software tools.
Since 2011 Kharkiv Asteroids and Comets Group cooperates with ISON in space
debris observations.
Chuguev Observation Station
Institute of Astronomy of Karazin Kharkiv National University, UKRAINE
70-cm telescope
25-cm telescope
(ISON donated CCD-camera) (ISON donated the instrument)
Kharkiv Asteroids and Comets
Group
(15898) KharAsterTeam
ASTEROID HAZARD PROBLEM:
Contribution from the Optical Observations
• Discovery of new NEAs. Particularly important discovery of
asteroids, which are potentially dangerous for human civilization
• Observations of newly discovered objects in a follow-up mode to
determine their coordinates and to estimate sizes of these
bodies
• The study of the physical properties of NEAs (rotation,
composition, shape etc) needed to prevent any future collisions
with the Earth.
The Asteroid Subsets
Two subsets were formed in the frame of ISON for
asteroid’s observations during last three years:
(I) Several telescopes (with apertures 40 cm – 2.6 m) are involved in
carrying out photometry of asteroids. Also they are used for
observations of GRB afterglow.
(II) Two wide-field of view telescopes (46 cm and 60 cm) are used for
searching asteroids. The main objects of our interest are NEAs.
(III) We are forming 3rd subset of ISON for newly detected NEAs orbit
improvement. These telescopes will be able to participate in
supporting the alerts of the Gaia mission.
The Network Observatories
Photometric Telescopes in Network
Existing telescopes with diameters from 60 cm up to 2.6 m have been modernized
within the ISON framework to use in the network: Gissar (Tajikistan), Lisnyky (Ukraine),
Chuguev (Ukraine), Simeiz (Ukraine), Abastumani (Georgia), Mayhill (USA), Maidanak
(Uzbekistan), Nauchny (Ukraine)
Asteroid Photometry
The primary aims:
• Characterization of the Near-Earth Asteroids (newly discovered ones
and especially Potentially Hazardous Asteroids (PHAs)) that includes
determination diameters, shapes, rotation periods, surface properties
of the bodies.
• Searching for binary asteroids and determining parameters of the
binary systems
• Investigation of Yarkovsky-O’Keeffe-Radzievskii-Paddack effect (YORPeffect) – detection of the influence on asteroid’s rotation
• Support radar observations of NEAs in optics
NEAR-EARTH ASTEROID LIGHTCURVES
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Main Results of Asteroid Photometry
In past 3 years more then 60 NEAs were observed in the frame of ISON and
the main results were attained:
• more then 200 lightcurves were obtained;
• 10 asteroids were observed to investigate of the YORP effect, and for 3 of
them the YORP was detected;
• 14 new determinations of rotation periods were done;
• 6 from the obtained periods found to be longer 16 hrs;
• 2 super-fast rotators were found: 2001 FE90, 326290 1998 HE3;
• 2 binaries were found: 8373 Stephengould, 3352 McAuliffe; and another 3
NEAs were suspected as binaries;
• absolute magnitudes and BVRI colors were obtained for about 20% for the
observed asteroids.
YORP Investigations
In results of the lightcurve observations an influence of the Yarkovsky-O’KeeffeRadzievskii-Paddack effect on asteroid rotation was detected/confirmed for 3
NEAs (Apollo, Geographos, Eger). The work are performed in collaboration with
David Vokrouhlicky and Josef Durech from Institute of Astronomy of Charles
University (Prague, Czech).
It is 3 of 4 asteroids with the YORP detected to the date.
Apollo
Geographos
Hv
11,8
Relative magnitude R
1862 Apollo
Eger
1620 Geographos
14.8
12,0
15.2
12,2
15.6
16.0
12,4
April 2007
0,0
0,2
0,4
0,6
0,8
Febr. 2008
1,0
Rotational phase
Kaasalainen et al. 2007;
Durech et al. 2008
0.0
0.2
0.4
0.6
0.8
1.0
Rotational phase
Durech et al. 2008
Durech et al. 2009
Binary Asteroids
1.
Searching for binary asteroids and determining parameters of the binary
systems is performed in cooperation with Czech astronomers from
Ondrejov Astronomical Observatory, Czech Academy of Sciences.
2.
To obtain the good results for searching / investigation of binary system
we need in regular observations, and as usually as it should be
observations during several consecutive nights. The best way to detect
and investigate the binary asteroid is to observe the object from several
obsevatories located at different longitudes.
Binary Asteroids
8373 Stephengould – discovered as binary and then
this system was investigated in the project in 2010
15,2
15,4
15,6
15,8
8373
12,2
Relative magnitude R
Reduced magnitude R
8373
12,4
12,6
12,8
- Jan. 18, 2010
- Jan. 17, 2010
16
18
20
22
UT(c)
24
26
28
16
18
20
22
UT(c)
24
26
28
Asteroid Radar Shape Models:
Lightcurves of NEA 8567 1999 HW1
8,8
8567 1999 HW1
14,6
8567 1999 HW1
9,0
Relative magnitude R
Magnitude R(1,=0)
14,8
15,0
15,2
15,4
15,6
- Aug 2008
9,4
9,6
9,8
10,0
- Jul 2008
15,8
9,2
- Aug 2008
- Sep 2008
P = 8.756hrs
P = 8.753 hrs
10,2
0,0
0,2
0,4
0,6
Rotational phase
July-August 2008
0,8
1,0
0,0
0,2
0,4
0,6
0,8
1,0
Rotational phase
August-September 2008
16
Shape Model of 8567 1999 HW1:
Radar and Photometry
Magri et al. (2011), Icarus 214, 210-227
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NEA Searching in ISON
Two remotely controlled telescopes are involved in asteroid search:
• 45.5 cm telescope Centurion-18 at ISON-NM Observatory, Mayhill, USA (H15 );
• 60 cm telescope at Andrushivka Astronomical Observatory, UKRAINE (A50).
Both telescopes have a wide field of view: 100x100 and 51x51 arcmin.
45.5 cm telescope (f/2.8)
Mayhill, New Mexico
60 cm telescope (f/4)
Andrushivka, UKRAINE
Results of Surveys in 2011
H15 ISON-NM Observatory started an asteroid searching in July 2010.
•Obtained more than 185 000 observations
• Discovered more than 1000 MBA (provisional designation)
• Two near-Earth asteroids 2010 RN80 and 2011 QY37 (Amors)
• Long-period comet C/2010 X1 (Elenin)
• Short-period near-Earth (q=1.24) comet P/2011 NO1 (Elenin)
• Several Jovian Trojans
A50 Andrushivka Astronomical Observatory beginning asteroid survey in
2003, since 2008 in frame of ISON.
In 2011 there are 33034 measurements of 9339 asteroids and 3 comets with
the 60-cm telescope. It is 13th place from all observatories.
During 2012-2013 we are planning to install several new 40-65 cm telescopes
for asteroid search.
The World Results of Asteroid Surveys in
2011 (based on data provided by MPC)
№
MPC
Code
Name
Total
observations
Total
objects
Numbered Unnumbered
MPs
MPs
Comets
% Num.
MPs
% Unnum.
MPs
% Comets
1
G96
Mt. Lemmon Survey
1751716
238345
172227
66118
60
72.26%
27.74%
15.67%
2
704
LINEAR
1712623
124659
119064
5595
74
95.51%
4.49%
19.32%
3
703
Catalina Sky Survey
1349735
136545
122517
14028
66
89.73%
10.27%
17.23%
4
F51
Pan-STARRS 1
1270637
214701
160693
54008
53
74.85%
25.15%
13.84%
5
691
Spacewatch
686175
112611
86115
26496
19
76.47%
23.53%
4.96%
6
E12
Siding Spring Survey
213861
31052
29028
2024
20
93.48%
6.52%
5.22%
7
D29
Purple Mountain Obs.
185854
40523
37627
2896
11
92.85%
7.15%
2.87%
8
H15 ISON-NM Observatory*
135302
30818
27188
3630
43
88.22%
11.78%
11.23%
9
106
Črni Vrh Observatory
85133
18770
17989
781
9
95.84%
4.16%
2.35%
10
291
Spacewatch II
52006
12982
8606
4376
28
66.29%
33.71%
7.31%
A50
Andrushivka Obs.*
33034
9339
8634
705
3
92.45%
7.55%
0%
…
13
* - ISON observatories
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Observations of Gamma-Ray Bursts
GRB is most powerful transient event in gamma-ray domain (up to 10^54 erg
per few seconds). It is cosmological phenomenon (currently directly observed
up to redshift z=9.4). However since its discovery more than 40 years ago,
there is no detailed physical model of the phenomenon.
The sources of the GRB can be:
Rare type of Supernovae type Ib/ Ic
Merging compact relativistic binary system
GRBs emit in wide energy bands, including optic
What is place of ISON in
GRB observations?
• Small aperture telescopes (20 – 50 cm) are still valuable
instruments for GRB investigation!
• Early and prompt optic observations after gamma-detection
(e.g. GRB 120308A in ISON-NM taken 70 s after burst trigger,
GRB 100901A taken 10 min after trigger in ISON-Milkovo
Observatory)
• Detailed light curve of rare bright afterglows (e.g. 090328A
taken in Kharkiv Observatory)
Alert Observations of GRB 120308A
in ISON-NM Observatory
06:16:55 UT
t-t0,d — 0.00245
mag - [18.13m]
exp — 30s
Conclusion
ISON project clearly demonstrates benefits of international
scientific collaboration in various aspects of optical
observations.
ISON promotes cooperation between observatories in developing
nations and scientific organizations in industrialized countries.
Joint efforts of BSSI and ISON on establishing of new telescope
facilities and involvement of existing observatories will help to
improve the overall level of research.