-- okénko do vesmíru
Nedávno vydala firma Rubico vzdělávací CD-ROM s astronomickou tematikou nazvaný Gallaxis. Nejedná se ale v žádném případě o pokus konkurovat cyklu Astro 2001 a kolektiv autorů sdružený kolem Hvězdárny ve Valašském Meziříčí ani nic takového neměl v úmyslu. Toto dílko se hodí především jako první krok pro ty, kteří s astronomií teprve začínají a kteří se posléze obrátí na specializovanější literaturu.
Obálka CD s "kupodivu" astronomickými motivy působí poměrně sympaticky. Na zadní straně se vám dostane náležitého vysvětlení, co uvnitř naleznete a je tu odkaz na další produkty vydavatele. Po zasunutí do mechaniky se objeví logo produktu a nabídka instalace některého z internetovských prohlížečů. Celý text je totiž ve formátu HTML a proto je nutné mít nainstalován prohlížeč (na výběr jich stejně moc není). Samotné CD se dělí na dvě části -- Gallaxis Text, což je vzdělávací text s obrázky a animacemi a Gallaxis Find, kde se podle klíčových slov vyhledávají obrázky z databáze. Text je pojat jednoduchou formou a působí dojmem klasické internetovské stránky, která je kvůli přenosové rychlosti co nejvíce "očesaná". To je trochu škoda, protože srovnávat propustnost Internetu a mechaniky asi nejde. Na druhou stanu je HTML dost omezený nástroj a nelze s ním dělat zázraky. Text je psán příjemnou formou, ale je bohužel rozdělen do několika superdlouhých HTML stránek, které se poměrně dlouho načítají. To se projeví hlavně při přeskakování mezi textem a obrázky. Dojem také trochu kazí podivné ovály tvořící podklad nadpisu kapitol. Navíc u dlouhých názvů text mírně přelézá přes okraj oválu. V textu najdete velké množství obrázků vždy k danému tématu, které jsou ve většině případů přejaté z NASA. Na konci textové části jsou umístěné pěkné animace nejrůznějších astronomických jevů a událostí. Bohužel jsou všechny pohromadě na konci textu, ačkoli by bylo asi lepší je umístit do textu jako dokreslení výkladu.
Celkový dojem z titulu je ale rozhodně kladný. Mohl by se stát dobrou učební pomůckou pro školy a vodítkem pro neastronomicky zaměřené středoškolské profesory fyziky, případně pro potenciální zájemce o astronomii. O tom, jak moc vstoupí do podvědomí širších vrstev, ale asi rozhodne jeho cena.
CD-ROM Gallaxis, vydala firma Rubico ve spolupráci s Hvězdárnou Valašské Meziříčí. Cena 399,- Kč.
Kam patří Pluto?
V posledni dobe probihala mezi profesionalnimi astronomy debata o statutu Pluta, zda jej povazovat za planetu ci nikoli, pripadne zda mu dat "dvoji obcanstvi", tedy povazovat jej za planetu ale zaroven mu dat i planetkove cislo. Tato debata byla z casti motivovana take tim, ze v nejblizsi dobe bude prideleno planetkove cislo 10000 a nekteri astronomove navrhovali dat toto cislo prave Plutu. Protoze vsak v zadnem z techto bodu nebylo mozno dosahnout mezi odborniky shody, rozhodla se Mezinarodni astronomicka unie (IAU) zachovat stavajici stav. Jak vyplyva z prilozeneho tiskoveho prohlaseni IAU, Pluto je dale povazovano za planetu a nedostane zadne planetkove cislo. Probiha ovsem debata o tom, ze by Pluto dostalo cislo v ramci mozneho noveho cislovaciho systemu pro transneptunicke objekty. (V tom pripade by mezi nimi melo cislo 1.) Bylo by tedy povazovano za planetu, ktera je ovsem clenem pasu transneptunickych teles. Jako to dopadne vsak jeste teprve uvidime. Pluto si vsak v kazdem pripade svuj statut planety zatim udrzuje.
Recent news reports have given much attention to what was believed to be an initiative by the International Astronomical Union (IAU) to change the status of Pluto as the ninth planet in the solar system. Unfortunately, some of these reports have been based on incomplete or misleading information regarding the subject of the discussion and the decision making procedures of the Union.
The IAU regrets that inaccurate reports appear to have caused widespread public concern, and issues the following corrections and clarifications:
1. No proposal to change the status of Pluto as the ninth planet in the solar system has been made by any Division, Commission or Working Group of the IAU responsible for solar system science. Accordingly, no such initiative has been considered by the Officers or Executive Committee, who set the policy of the IAU itself.
2. Lately, a substantial number of smaller objects have been discovered in the outer solar system, beyond Neptune, with orbits and possibly other properties similar to those of Pluto. It has been proposed to assign Pluto a number in a technical catalogue or list of such Trans-Neptunian Objects (TNOs) so that observations and computations concerning these objects can be conveniently collated. This process was explicitly designed to not change Pluto's status as a planet.
A Working Group under the IAU Division of Planetary Systems Sciences is conducting a technical debate on a possible numbering system for TNOs. Ways to classify planets by physical characteristics are also under consideration. These discussions are continuing and will take some time. The Small Bodies Names Committee of the Division has, however, decided against assigning any Minor Planet number to Pluto.
3. From time to time, the IAU takes decisions and makes recommendations on issues concerning astronomical matters affecting other sciences or the public. Such decisions and recommendations are not enforceable by national or international law, but are accepted because they are rational and effective when applied in practice. It is therefore the policy of the IAU that its recommendations should rest on well-established scientific facts and be backed by a broad consensus in the community concerned. A decision on the status of Pluto that did not conform to this policy would have been ineffective and therefore meaningless. Suggestions that this was about to happen are based on incomplete understanding of the above.
The mission of the IAU is to promote scientific progress in astronomy. An important part of this mission is to provide a forum for debate of scientific issues with an international dimension. This should not be interpreted to imply that the outcome of such discussions may become official IAU policy without due verification that the above criteria are met: The policy and decisions of the IAU are formulated by its responsible bodies after full
deliberation in the international scientific community.
General Secretary, IAU
Jak patrno z prilozeneho MPEC, moznost, ze Pluto dostane planetkove cislo 10000 (a tedy bude mit dualni statut, bude o nem mozno hovorit jako o planete i planetce, podle kontextu) neni ještě uzavrena. Ti astronomove, kteri planetky ci komety pozoruji, mají moznost se k tomu vyjadrit, kterou moznost podporuji. Uvidime tedy (jiz v breznu), jak to nakonec s Plutem a planetkovym cislem 10000 dopadne.
On 1801 Jan. 1 Guiseppe Piazzi discovered the object between Mars and Jupiter that he called Ceres Ferdinandea, "the eighth planet". Following the discovery a year later of a similar object, and in subsequent years further objects in what might be termed the "Cisjovian Belt", Piazzi's discovery eventually became known under either the name Ceres or the symbol (1), where the numeral, originally placed inside a complete circle, indicated that this was the first object found in that region of the solar system. By 1849 the sequence of discoveries in the region had reached (10), and 1868 saw the discovery of (100). By 1923, when (1000) was announced, the set of objects, while still mainly members of that Cisjovian Belt (also known simply as the "Asteroid Belt", or "Main Belt" of "minor planets"), also included objects that approached within 0.1 AU of the earth or extended out to the orbit of Saturn.
Next month, we shall pass (10000) in what is a collection of small objects that are not obviously cometary (although three members do also have well-documented dual status in the Catalogue of Cometary Orbits) and travel around the sun in independent orbits (i.e., satellites are excluded) that are well determined (i.e., with one exception that will surely be eventually remedied, the positions of the objects are very precisely predictable). Again, although the vast majority of the objects are in the Cisjovian Belt, there are members that are at perihelion significantly closer to the sun than Mercury or are at aphelion beyond the orbit of Neptune. It has been traditional to have a special celebration with each thousandth numbering. For example, (1000) was named in honor of the discoverer of Ceres, (2000) in honor of the discoverer of Uranus, (5000) in honor of the International Astronomical Union and (6000) in honor of the United Nations. Obviously, it would be appropriate to have some very special celebration to acknowledge (10000).
Most readers of these Circulars will be aware of recent discussions in the press concerning a proposal that the number (10000) should be given to Pluto. The principal reasoning for this is the recognition during the past few years that Pluto was the first discovered and largest known member of the "Transneptunian Belt" (sometimes called the "Kuiper Belt" or "Edgeworth-Kuiper Belt") of small objects beyond Neptune that possess some similarity, at least dynamically, to bodies in the Cisjovian Belt. Although as many as 95 members (or possible
members) of the Transneptunian Belt are now listed, most of the orbital solutions are very weak, and none of the bodies has so far been included in the collection of those with "guaranteed" orbit determinations. A few of the discoveries from 1992-1994 are now approaching this state, which will also allow them to receive permanent names.
Although it is not unlikely that further Transneptunian Objects as large as Pluto will be discovered in the future, Pluto obviously holds a very special place in our appreciation of this new population, and by assigning to it the number (10000), we should guarantee that Pluto will be at the head of the Transneptunian list. It is also very important to affirm that there is absolutely no implied "demotion" or "reclassification" of Pluto from its position
in the list of the "planets" (or "major planets" or "principal planets"). Unfortunately, many of the articles that have appeared in the press have accidentally (or deliberately) misinterpreted this issue. As with (2060) = 95P/Chiron, (4015) = 107P/Wilson-Harrington and (7968) = 133P/Elst-Pizarro, where the choice of "minor planet" or "comet" designation depends on the context, we are proposing that Pluto would have dual status as a "major" and a "minor" body. Readers of these Circulars, in particular, will appreciate that Pluto is sufficiently fainter than the other major planets that it can be confused with many other minor planets. We have in fact identified observations of Pluto several times during the past couple of years in data reported by the survey programs for Near-Earth Objects, and some astrometric observers specifically report to us observations of Pluto. There is currently no outlet for publishing these observations. It should be emphasized that the number (10000) would be used only in the context of publishing such observations or in matters directly related to Pluto's place in the Transneptunian Belt.
Much has been made in the press that the IAU is "voting" on Pluto's status, and at least one astronomical organization issued a press release on the subject. Members of the public seem completely baffled by this kind of attention. The question of relevance to the readers of these Circulars concerns the numbering and naming of (10000). Indeed, the IAU Small Bodies Names Committee has already been working on this particular matter for the past month or so. Progress is slow and uncertain, however, and there are some who think that democracy would be better served by seeking opinions from a larger, but informed community. The astronomers, amateur and professional, who contribute material to these Circularsastrometric observations, identifications, orbit determinations--are such an informed community.
Accordingly, any reader with an opinion on the subject is invited to e-mail it to us at the Minor Planet Center, preferably using the address email@example.com. Such a message could consist of a brief statement such as "I approve (10000) Pluto" or "I do not approve (10000) Pluto", although the value of the latter choice would be augmented if an appropriate alternative suggestion were made for (10000). Brief comments on the subject (preferably constructive) would also be welcome, and writers are encouraged to identify themselves. Modern bureaucracy rarely pays much attention to comments from even an informed public, but since this issue is of concern principally to our readers (more so, in fact, than to many professional astronomers with little or no interest in solar-systém astronomy who just happen to be serving on a committee), we feel that it is appropriate for us to solicit advice in this way. Your early response is desirable. It is not necessary that you actually subscribe to these Circulars in order to respond. Appropriate responses will be examined and considered in connection with the deliberations by the Small Bodies Names Committee by their deadline of Feb. 26.
Brian G. Marsden
Pluto nebude mit planetkove cislo. Podle prilozeneho MPEC, Minor Planet Center uznava rozhodnuti Komise pro jmena malych teles Mezinarodni astronomicke unie. Plati tedy to tiskove prohlaseni IAU z 3. unora. Jmeno pro planetku cislo 10000 bude teprve vybrano.
A clarification is necessary with regard to the Editorial Notice on MPEC 1999-C03. As shown at the end of the Notice, this was reprinted from MPC 33615-33616, which had been prepared two days earlier. The pressure of work to prepare the monthly batch of MPCs prevented the preparation of a new Notice when MPEC 1999-C03 was issued.
In the mean time, as many readers will realize, a Press Release was issued by Johannes Andersen, the IAU General Secretary, noting very clearly that Pluto would in no way be "demoted", a point made, equally strongly, in the Minor Planet Center's Editorial Notice. The Press Release also clarified that the Small Bodies Names Committee had, in the mean time, decided not to use the number (10000) for Pluto.
The main purpose of our Editorial Notice, also clearly stated, was to select an appropriate name for (10000), given that the Feb. 2 batch of Minor Planet Circulars contains numberings through (9999).
In this regard, other than with its decision on Pluto, the SBNC did not complete its charge. It expects to make an appropriate decision on a name for (10000) by Feb. 26, now with the help of information received as a result of the invitation to readers in our Editorial Notice.
Some 24 hours now after MPEC 1999-C03 was issued, the messages received are 63 percent in favor of using (10000) for Pluto, 37 percent against. The in-favor fraction has fluctuated between 58 and 68 percent, suggesting that the vote represents a genuine international concern, not one influenced by any campaign. Unfortunately, there have been few suggestions of alternatives, and no obvious candidates have yet emerged. The SBNC will consider all of this information in its further deliberations, and it is to be hoped that the outcome will be a wise decision of which the IAU can be proud.
Although the experiment is now officially at an end, there is obviously still a need for appropriate alternatives to Pluto. Given the precedents listed in the second paragraph of MPEC 1999-C03, we should like the name of (10000) to be on a suitably grand scale. I thank everyone who participated. I also apologize to any astronomers who feel in any way slighted by my remarks on this subject, but it is also very clear that the "Pluto issue" is a very emotional one, separate from any scientific or historical considerations. I particularly apologize to my good friends Johannes Andersen, IAU Assistant General Secretary and Commission 20 President Hans Rickman, and Division III President Mike A'Hearn, for any confusion caused by the timing of yesterday's statement, and I thank them for their support during this trying time.
Brian G. Marsden