4897 Tomhamilton
Encyclopedia
4897 Tomhamilton is a Main Belt
minor planet
. It was discovered by Eleanor F. Helin
at the Palomar Observatory
on August 22, 1987. Research shows that it was previously recorded on photographs taken as early as 1950, and was even logged as 1971QV1.
It is named after Thomas Wm. Hamilton, an American (born San Francisco, 1939) who was a child actor (he played Barnaby
in Barnaby and Mr. O'Malley and was on the early television
show Mr. I-Magination
). As an adult he worked on the Apollo program, determining fuel requirements and radar
accuracy requirements for lunar orbit rendezvous
. He later worked as an astronomy educator and planetarium
director, and is the author of a time travel
adventure novel, Time for Patriots (ISBN 978-1-60693-224-7). Hamilton and Helin were acquainted, as he had interviewed her at an astronomical conference for a cable television show he was producing at the time.
This asteroid was last at opposition on November 2, 2009, at a distance from Earth of 2.138 astronomiucal units. Next opposition is January 11, 2011 (coinciding with Hamilton's 72nd birthday) at a distance of 2.476 astronomical units.
Given the moderately elliptical orbit, this asteroid can on rare occasions reach an apparent magnitude
from Earth of about +10.9. Size, shape, density
, and rotational period are not yet known. A diameter of 30 to 35 miles (roughly 50 kilometers) is reasonable based on magnitude and a likely albedo
.
Asteroid belt
The asteroid belt is the region of the Solar System located roughly between the orbits of the planets Mars and Jupiter. It is occupied by numerous irregularly shaped bodies called asteroids or minor planets...
minor planet
Minor planet
An asteroid group or minor-planet group is a population of minor planets that have a share broadly similar orbits. Members are generally unrelated to each other, unlike in an asteroid family, which often results from the break-up of a single asteroid...
. It was discovered by Eleanor F. Helin
Eleanor F. Helin
Eleanor Francis "Glo" Helin was an American astronomer. She was principal investigator of the Near Earth Asteroid Tracking program of NASA's Jet Propulsion Laboratory. Some sources give her name as Eleanor Kay Helin...
at the Palomar Observatory
Palomar Observatory
Palomar Observatory is a privately owned observatory located in San Diego County, California, southeast of Pasadena's Mount Wilson Observatory, in the Palomar Mountain Range. At approximately elevation, it is owned and operated by the California Institute of Technology...
on August 22, 1987. Research shows that it was previously recorded on photographs taken as early as 1950, and was even logged as 1971QV1.
It is named after Thomas Wm. Hamilton, an American (born San Francisco, 1939) who was a child actor (he played Barnaby
Barnaby
Barnaby was a comic strip which began April 20, 1942 in the newspaper PM and was later syndicated in 64 American newspapers ....
in Barnaby and Mr. O'Malley and was on the early television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...
show Mr. I-Magination
Mr. I-Magination
Mr. I. Magination was one of the earliest television shows for children. It ran live as a half-hour weekly show on CBS from 1949 to 1952.Mr. I. Magination was one of the earliest television shows for children. It ran live as a half-hour weekly show on CBS from 1949 to 1952.Mr. I. Magination was...
). As an adult he worked on the Apollo program, determining fuel requirements and radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...
accuracy requirements for lunar orbit rendezvous
Lunar orbit rendezvous
Lunar orbit rendezvous is a key concept for human landing on the Moon and returning to Earth.In a LOR mission a main spacecraft and a smaller lunar module travel together into lunar orbit. The lunar module then independently descends to the lunar surface. After completion of the mission there, a...
. He later worked as an astronomy educator and planetarium
Planetarium
A planetarium is a theatre built primarily for presenting educational and entertaining shows about astronomy and the night sky, or for training in celestial navigation...
director, and is the author of a time travel
Time travel
Time travel is the concept of moving between different points in time in a manner analogous to moving between different points in space. Time travel could hypothetically involve moving backward in time to a moment earlier than the starting point, or forward to the future of that point without the...
adventure novel, Time for Patriots (ISBN 978-1-60693-224-7). Hamilton and Helin were acquainted, as he had interviewed her at an astronomical conference for a cable television show he was producing at the time.
Orbital details
- eccentricityOrbital eccentricityThe orbital eccentricity of an astronomical body is the amount by which its orbit deviates from a perfect circle, where 0 is perfectly circular, and 1.0 is a parabola, and no longer a closed orbit...
0.1259094 - semimajor axis 3.0527658 Astronomical UnitAstronomical unitAn astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
s - perihelion 2.6683939 Astronomical Units
- aphelion 3.4371377 Astronomical Units
- inclinationInclinationInclination in general is the angle between a reference plane and another plane or axis of direction.-Orbits:The inclination is one of the six orbital parameters describing the shape and orientation of a celestial orbit...
to eclipticEclipticThe ecliptic is the plane of the earth's orbit around the sun. In more accurate terms, it is the intersection of the celestial sphere with the ecliptic plane, which is the geometric plane containing the mean orbit of the Earth around the Sun...
11.06787 degrees - ascending node 188.49398 degrees
- argument of perihelion 108.14456 degrees
- period 5.33 Earth years
- absolute magnitudeAbsolute magnitudeAbsolute magnitude is the measure of a celestial object's intrinsic brightness. it is also the apparent magnitude a star would have if it were 32.6 light years away from Earth...
+11.6
This asteroid was last at opposition on November 2, 2009, at a distance from Earth of 2.138 astronomiucal units. Next opposition is January 11, 2011 (coinciding with Hamilton's 72nd birthday) at a distance of 2.476 astronomical units.
Given the moderately elliptical orbit, this asteroid can on rare occasions reach an apparent magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
from Earth of about +10.9. Size, shape, density
Density
The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is ρ . In some cases , density is also defined as its weight per unit volume; although, this quantity is more properly called specific weight...
, and rotational period are not yet known. A diameter of 30 to 35 miles (roughly 50 kilometers) is reasonable based on magnitude and a likely albedo
Albedo
Albedo , or reflection coefficient, is the diffuse reflectivity or reflecting power of a surface. It is defined as the ratio of reflected radiation from the surface to incident radiation upon it...
.
External links
- JPL Small-Body Database Browser
- http://sbpra.com/ThomasWmHamilton