AIPS. It will get you eventually...


| Experience | Cookbook | Warranty | Hoax | God | The Future | Back to Main Page |

The typical astrophysics student is a despondent individual, already resigned to the fact that he (for they are rarely female) has made a considerable social and financial error in following his boyhood dream of being, like Patrick Moore, an astronomer. This, and the mixture of arcane practices and customs that is astrophysics in general and AIPS in particular, leads to an unusually rich field of niche humour in astrophysics coffee-rooms, most of which isn't actually funny, and all of which is only understood by a handful of people in the world. Long term residence at observatories in the middle of nowhere, particularly Jodrell Bank, is known to accentuate this humour problem very quickly - sometimes to such an extent that it becomes untreatable.

The AIPS experience

For a typical new postgraduate student (age 21-ish, degree in physics, astronomy or chemistry), the first encounter with the software that is AIPS is a strange and unsettling experience of Palaeolithic mysticism. Whilst astrophysics students are likely to be used to Unix-style command line interfaces, nothing will have prepared them for what they are about to receive. The shock that AIPS is not at all like the software used to discover alien messages in the VLA control-room by Jodie Foster in the film Contact, is a heavy blow - the first of many.

The Cookbook

The first surprise is the Cookbook. The AIPS manual is formatted as a cookbook full of recipes, where data ingredients are calibrated together to form some kind of cake (usually an image). Interspersed with these fiendish recipes are real recipes, often involving bananas. This is presumably in reference to the pun of AIPS with apes, and is an indication of the humour that will follow and evolve. The cookbook of course is littered with small images of apes, and typically has an ape on the front cover - mimicking the AIPS icon itself, which is, predictably, an ape.

No Warranty

Upon starting AIPS for the first time, the condemned student is immediately presented with a blunt statement of fact:

"AIPS comes with ABSOLUTELY NO WARRANTY"

In the insecure student's mind this immediately raises the spectre that some kind of disk-wiping crash is likely and indeed imminent, and panic sets in. This state of panic is one that remains whenever an astrophysicist is using AIPS, particularly when tampering with the more intimidating routines such as FRING, CLCAL, or the mighty IMAGR. (NB those who pronounce IMAGR to rhyme with "Voyager" still have hope; those who make it rhyme with "Grrr" are beyond help).

In fact, crashes are exceptionally rare, and the AIPS "Dump" File (colloquially "ape-shit") is rarely produced. If one wonders why there was the need to frighten the new AIPS user with talk of warranties, then one is clearly not an astrophysicist. The AIPS experience is very much less WYSIWYG and very much more WYGIWYD (What you get is what you deserve).

The Interferometry Hoax

At some point during the second postgraduate year it becomes obvious to a typical VLBI postgraduate that radio interferometry is an elaborate hoax (like gravitational lensing), invented to keep astrophysics researchers in jobs. This is easily proved by getting two astrophysicists to stand 100m from a board of small text, and asking them to tell each other what they see on the board. The physical process of telling each other what they are seeing (i.e. Interferometry) does not make the tiny text become visible at 100m.

Being a resigned and accepting kind of people, the realisation that their PhD is based on a lie is not a great blow to most astrophysicists; indeed it is a small blow compared to the numerous painful blows already felt by this time (e.g. that they will never own a house, or a Ferrari, or visit somewhere warm that isn't a barren desert observatory, or visit a mountain that isn't a cold desolate observatory, or visit Hawaii for anything other than being in the clouds, or get to talk to a beautiful woman). Rather, this realisation inspires the search for a greater truth: where do the generated images come from?

AIPS as a gift from God

Images produced from the recorded observatory data fed into AIPS have been shown to be true enhancements of that data. So, by the third year of his PhD, the astrophysicist is chasing the origin of these images. There is only one possible answer to this conundrum, and that is that AIPS was written by God. Every copy of AIPS contains hidden in its core codes, encrypted by unbreakable Holy algorithms, an exact copy of the true and original blueprint of the Universe as conceived by God Himself in the moment of the Big Bang, approx 15Gy ago.

What AIPS does during the calibration process is remarkable. It uses the supplied data to extract a perfect image of the source at infinite resolution from the Holy Blueprint. Then, the various AIPS routines add, one after the other, layer upon layer of carefully calculated noise and image distortion, so as to eventually produce an image of the quality and resolution that would be predicted from the cock and bull theory of VLBI interferometry.

The question then arises: "Why not refine VLBI interferometry so that the production of perfect images without noise are allowed". Unfortunately, by this time, the young astrophysicist has submitted his PhD, got a tedious job as a software engineer, bought a house, a Ford fiesta, and is spending his time playing computer games and has forgotten what he used to know about VLBI. He should consider himself lucky...

The Future

Using AIPS is like riding a bike - you never forget how to do it. Many years in the future, former AIPS users get cold shivers when the unprovoked thought of [tget imagr] pops into their head. At that point the follow-up thought is usually: I wonder if AIPS++ is finished yet? (To which the reliable answer is NO!)

PS This was briefly a Wikipedia page, but the morons there still believe in VLBI and deleted the page thinking it was "satire". You can take a horse to water...


Created 23/03/06 - - Last update 17/05/22
Mark Wright