The Minor Planet (Asteroid): “Tonycook”

Figure 1. The “Mathilde” asteroid as imaged by the NASA spacecraft NEAR in 1997. A NASA image.




What is an Asteroid?


An asteroid is a small lump of rock that lies, usually, in the asteroid belt, between the orbits of Mars and Jupiter. Their sizes can range from just a few metres up to a few hundred km. They are the remains of early solar system planet formation which may not have come together, some maybe dead comets, whilst others maybe the result additional collisions between asteroids.




The Discovery:


The asteroid was discovered by the Catalina Sky Survey of the Lunar and Planetary Laboratory at the University of Arizona in Tucson on May 7th 2003, by a team of astronomers. Richard Hill, one of the team members told me that they find so many asteroids that it is not possible to say who on the team actually discovered individual ones.  In order to be a confirmed asteroid it must be observed on two different nights. They also have to make sure that it has not already been discovered. So confirming the discovery of an asteroid is never a short process.


As there are likely to be between 1 and 3 million asteroids out there, larger than 1 km in diameter (mostly between the orbits of Mars and Jupiter), astronomers provisionally allocate a number to the asteroids, so in the above case it was called “2003 JO13”, at least until they could think of a better name.





The Naming of:


The convention for naming asteroids is that the observer, or team of observers who discover it, have up to 10 years to allocate it a name, and unlike names of craters on planets and moons which have specific themes (e.g. on Mercury they are named after artists, poets, philosophers etc., on Venus they are named after famous women, and on Mars, war related gods etc.), the naming of asteroids is a bit of a free for all. In the early years of discovery they were named typically after gods, but have in more recent times been named after the discoverer’s relatives and friends, their favourite musicians, places visited, and even their pets as is the case of “Mr Spock” – though pet names are now banned! Searching through modern names of asteroids you can see that those involved with asteroid mission have featured as too winners of US high School student science project competitions.


My name was selected for asteroid 2003 JO13 on the basis of outreach work I do with amateur astronomers who study the Moon as four other UK amateur astronomers had asteroids named after them in the same year: Grego, Leatherbarrow, Haroldhill, and Longshaw. However it also recognizes some earlier planetary cartography work. As to why my asteroid was named “Tony Cook” rather than “Tony Cook” or just “Cook”, this appears to be because Cook is a common name and so could be confused with others with a similar surname. Also these days they prefer single word names to multiple words as these slip off the tongue better when spoken and are perhaps easier to remember. Hence its full title is now: 95928 Tonycook as it’s the 95928th asteroid held in the International Astronomical Union’s catalog of minor planets.


Note that I categorically do not own this asteroid, it’s simply been given my name in a similar way to which large boats, aircraft or trains are given names. However I will be keeping a close eye on any research published about this asteroid.




What We Know About the Asteroid:


All we know are is its orbit and brightness. It is simply too far away to see anything other than a dot on any images taken, so it would look like any other star! However the orbit and brightness tell us a lot and here is what I have been able to figure out:


Minimum distance to Sun

340 million km

Maximum distance to Sun

470 million km

Closest distance to Earth

190 million km

Orbital inclination

13.2˚ - slightly inclined out of the plane of the solar system

Orbital period (an asteroid year)

4.44 years

Rotation period (an asteroid day)


Brightest magnitude

+18 or 63 thousand times fainter than the faintest naked eye star

Faintest magnitude

+21 or 1 million times fainter than the faintest naked eye star






Unknown – but asteroids are often irregular


4% to 20% are a typical range of values for asteroids at this distance from the Sun

Minimum diameter

2.3 km – if we approximate its shape as a sphere and take the brightest reflectivity

Maximum diameter

6.3 km – if we approximate its shape to a sphere and take the darkest reflectivity

No. of moons

Unknown, but very occasionally some asteroids do have moons


Given that there are so many asteroids, it will take a while before we find out its rotation period, colour, composition and approximate shape, and it may be many decades before it is visited by spacecraft and we learn what it really looks like, and whether it has any moons. However to give an approximate idea of minimum and maximum sizes - if we approximated it to a spherical shape, see Fig. 2 below:



Figure 2. The size of asteroid Tonycook compared to the West Wales coastal town of Aberystwyth, Two sizes are given. The smaller is if the asteroid is bright at 20% reflectivity. The larger is if the asteroid is dark with just 4% reflectivity. Note that asteroids this small are usually irregular in shape and so the above circular profiles are approximations only.



Where to Find the Tonycook Asteroid:


Figure 3. Orbital information about asteroid 95928 Tonycook from the NASA JPL SSD web site


The NASA Solar System Dynamics website will give you all the information you need. Just click on:  and then type in the asteroid name Tonycook, and press the return key (See Fig 3). If you want to visualize the orbit in 3D, click on the Orbit diagram button (see Fig 4) - though you may need to change preferences in your browser to get this to work properly. Budding amateur astronomers, with good deep sky imaging capability, can even have a go at trying to find the asteroid, based upon the sky coordinates found by pressing the ephemeris button (see Fig 5).


. Figure 4. Visualisation of the orbit of asteroid 95928 Tony Cook from the NASA JPL SSD web site



Figure 5. Coordinates in the sky of asteroid 95928 Tonycook, from the NASA JPL SSD website




Asteroids Named after Brits, or Associated with British Culture:


The following is a non-inclusive list. If I have missed any out, please let me know!


Minor Planet


12 Victoria

A Roman goddess but also of the same name as the British Queen

42 Isis

An Egyptian goddess, but also the first name of Pogson (an astronomer’s) daughter

281 Lucretia

Caroline Lucretia Herschel – a British astronomer

359 Georgia

Named after King George II, who was also the founder of a University in Göttingen

876 Scott

Sir Captain Scott of the Antarctic

1241 Dysona

Frank Watson Dyson – the 9th Astronomer Royal

1830 Pogson

Norman Pogson – British Astronomer who observed from Madras Observatory, India

1877 Marsden

Brian Marsden – a British Director of the Minor Planets Center

1996 Adams

John Couch Adams – Mathematician/Astronomer who jointly predicted where Neptune would be found

2000 Herschel

Sir William Herschel - Discover of the Planet Uranus

2099 Öpik

Ernst Öpik, an Estonian astronomer who worked at Armagh Observatory in Northern Ireland

2246 Bowell

Edward Bowell – a British astronomer studying minor planets at Lowell Observatory, Flagstaff

2383 Bradley

James Bradley – the 3rd Astronomer Royal

2591 Dworetsky

Mike Dworetsky - astronomer from University College London

2602 Moore

Popular TV Astronomer and author

2635 Huggins

Sir William Huggins – a pioneer of spectroscopy in astronomy

2675 Tolkien

J.R.R. Tolkien - the author of the Hobbit and Lord of the Rings

2688 Halley

Sir Edmund Halley, 2nd astronomer Royal and predicted the return of Halley’s Comet

2830 Greenwich

Observatory and prime meridian

2940 Bacon

Sir Francis Bacon an Elizabethan Scholar

2985 Shakespeare

Sir William Shakespeare - playwright

2991 Bilbo

The main character from the Hobbit

3018 Godiva

Lady Godiva

3062 Wren

Sir Christopher Wren, the architect

3078 Horrocks

 Jerimiah Horrocks – English Astronomer

3174 Alcock

George Alcock – A Peterborough amateur astronomer who discovered novae and comets


Dr Who's time machine

3697 Guyhurst

An amateur astronomer who edits The Astronomer publication

4040 Purcell

Henry Purcell – Composer

4984 Hollis

Andrew Hollis – Director of the British Astronomical Association Asteroid Section

4110 Keats

John Keats – Poet

4124 Herriot

Author of All Creatures Great and Small

4147 Lennon

John Lennon - one of the Beatles

4148 McCartney

Paul McCartney - one of the Beatles

4149 Harrison

George Harrison - one of the Beatles

4150 Starr

Ringo Starr - one of the Beatles

4305 Clapton

Eric Clapton - Musician

4326 McNally

Derek McNally – a British Astronomer

4370 Dickens

Charles Dickens - the famous author

4506 Hendrie

 Malcolm Hendrie a British Astronomical Association Comet Section director

4587 Rees

Astronomer Royal

4749 Ledzeppelin

A rock band

4751 Alicemanning

 Alice Manning, wife of Brian Manning who discovered this asteroid

4818 Elgar

Sir Edward Elgar - composer

4923 Clarke

Arthur C. Clarke –the Science Fiction author

5048 Moriarty

A fictional character from the Sherlock Holmes stories

5049 Sherlock

A fictional character from the Sherlock Holmes stories

5050 Doctorwatson

A fictional character from the Sherlock Holmes stories

5099 Iainbanks

Iain Banks –Science Fiction author

5405 Neverland

A fictional location in the Peter Pan story

5805 Glasgow

The Scottish City

6042 Cheshirecat

A fictional cat from Alice’s Adventures in Wonerland

6156 Dall

Horace Dall – amateur astronomer specializing in instrumentation and astrophotography

6223 Dahl

Roald Dahl – Children’s author

6434 Jewitt

British Astronomer who discovered one of the first Kuiper Belt Objects

6440 Ransome

Arthur Ransome – Children’s author of Swallows and Amazons

6735 Madhatter

Fictional character from Alice in Wonderland

6736 Marchare

Fictional character from Alice in Wonderland

7010 Locke

John Locke – British Philosopher 7032 Hitchcock

7012 Hobbes

Thomas Hobbes – A Political Philosopher

7016 Conandoyle

Arthur Conan Doyle - Author of the Sherlock Holmes novels

7032 Hitchcock

Alfred Hitchcock – British born Hollywood film director and producer

7166 Kennedy

Malcolm Kennedy – Secretary of the Astronomical Society of Glasgow

7239 Mobberley

British amateur astronomer and past president of the British Astronomical Association

7470 Jabberwock

A fictional character from Alice in Wonderland

7498 Whitaker

Ewen Whitaker a British planetary scientist involved in lunar mapping at the University of Arizona

7603 Salopia

Another name for Shropshire

7644 Cslewis

Author of Alice in Wonderland

7672 Hawking

Stephen Hawking - Theoretical Physicist and Mathematician

7707 Yes

A rock and roll group

7966 Richardbaum

English Amateur astronomer involved in planetary observation

8000 Isaac Newton

Famous mathematician/astronomer

8077 Hoyle

Sir Fred Hoyle - originated the Steady State theory

8079 Bernardlovell

Radio Astronomer from Jodrell Bank

8110 Heath

English Amateur astronomer involved in planetary observation

8166 Buczynski

English amateur involved in lunar and deep sky observing

8236 Gainsborough

Thomas Gainsborough – Landscape and portrait painter

8237 Constable

John Constable – Landscape painter

8545 McGee

Hazel McGee - past president  of the British Astronomical Association

8749 Beatles

The 1960's pop group

8837 London

The capital city of England and the UK

8849 Brighton

English coastal city

8914 Nickjames

Amateur astronomer

9007 James Bond

Fictional spy character

9325 Stonehenge

Ancient observatory/place of worship

9342 Carygrant

Cary Grant – a British born Hollywood actor

9500 Camelot

King Arthur’s castle (fictional)

9617 Grahanchapman

A Monty Python member

9618 Johncleese

A Monty Python member

9619 Terrygilliam

A Monty Python member

9620 Ericidle

A Monty Python member

9621 Michaelpalin

A Monty Python member

9622 Terryjones

A Monty Python member

11020 Orwell

George Orwell - author of 1984

11626 Church Stretton

A town in the south of Shropshire

12760 Maxwell

JamesMaxwell – a Scottish Mathematician and Physicist

13070 Seanconnery

First actor who played James Bond

16197 Bluepeter

A British children’s TV programme

17078 Sellers

Sir Peter |Sellers - a British comedy actor

18610 Arthurdent

A character from Hitch Hiker's Guide to the Galaxy

19367 Pink Floyd

A rock group

19383 Rolling Stones

A rock group

20141 Markidger

A British amateur/professional astronomer

20468 Petercook

1960's comedian

20469 Dudley Moore

1960's comedian

24728 Scagell

Robin Scagell - a UK amateur astronomer

24997 Petergabriel

A rock musician and part of Genesis

25924 Douglasadams

Douglas Adams - author of Hitch Hiker's Guide to the Galaxy

28151 Markknopfler

Mark Knopfler, a guitarist from Dire Straits

37582 Faraday

Sir Michael Faraday - British scientist

39428 Emilybrontë

Emily Brontë - author of Wuthering Heights

39429 Annebrontë

The third of the Bronte sisters

44016 Jimmypage

Jimmy Patrick Page – a composer and guitarist in Led Zepperlin

90481 Wollstonecraft

Mary Wollstonecraft – an early women’s rights campaigner

95824 Elger

Thomas Elger - a British amateur astronomer and lunar observer

95852 Leatherbarrow

Bill Leatherbarrow - past president of the British Astronomical Association and director of the Lunar Section

95882 Longshaw

Nigel Longshaw - amateur astronomer, specializing in lunar drawings

95928 Tonycook

Physics lecturer at Aberystwyth University and amateur astronomer specializing in the Moon

95935 Grego

Peter Grego - amateur astronomer, author of many astronomy books, and a lunar observer

95980 Haroldhill

Amateur astronomer and lunar observer, author of the Lunar Portfolio

127005 Prachett

Terry Prachett - author of the Disc World novels


A rock group

266646 Zaphod

A character from Hitch Hiker’s Guide to the Galaxy

342843 Davidbowie

A British rock musician





Want to Learn More About Asteroids, Space etc. ?:


·         If you live in Wales, try to visit the Space Guard Centre at Knighton, where they actively check up on the positions of potentially dangerous Near Earth Asteroids.


·         Learn more about the International Astronomical Union about how to name objects in the Solar System and Beyond, from their website.


·         Have a telescope and want to observe asteroids – then take a look at the Asteroid and Remote Planets Section of the British Astronomical Association


·         Want to join a local astronomical society? Try Newtown or Cardiff Astronomical Societies or see the Federation of Astronomical Societies website.


·         Want to study BSc/MPhys level Astrophysics, Physics with Planetary and Space Physics, or Space Science and Robotics at Aberystwyth University? – click on the Department of Physics website and explore. Foundation year entry also possible!



Published: Dr Anthony Cook

Department of Physics


University of Aberystwth

Email: atc @

Home Page:


The information provided on this and other pages by me, Tony Cook (a t c @ a b e r . a c . u k )

is under my own personal responsibility and not that of Aberystwyth University. Similarly, any

opinions expressed are my own and are in no way to be taken as those of A.U.




Department of Physics

The University of Aberystwyth