1,542 reputation
1622
bio website msquant.sourceforge.net
location Århus, Denmark
age 50
visits member for 4 years, 8 months
seen 2 days ago

(Last updated 2014-08-23.)

I am mostly interested in making scientifically important observations, like timing occultations of or by Solar System bodies and measuring variable stars.

I am also interested in citizen science projects and participate in some of them, like Galaxy Zoo.

I have been an amateur astronomer since 1975 and have worked at the European Space agency's (ESA) technical centre in Holland, ESTEC, on the ARISTOTELES mission, an earth gravity mapping mission.

Approximate coordinates: 55°20 N, 10°20 E


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Jul
23
comment Which is the heaviest present day lifter (rocket)? And is it comparable to the Saturn V rocket?
John Paul, do you mean GTO or GEO?
Jul
22
comment Are we capable of discovering planets in the Andromeda galaxy?
Was that based on a single microlensing event or several?
Jul
21
comment Refraction and scattered light for NLCs
Two NLC movies from 2011-07-11.
Jul
21
comment Are orbits interior to Jupiter's orbit less stable than orbits exterior to Jupiter's orbit?
Pluto's orbit was shown to be chaotic some years ago (not necessarily unstable). Does it mean Neptune's orbit is also chaotic?
Jul
21
comment Refraction and scattered light for NLCs
@Geoff Gaherty: the season started late this year. I saw some magnificent ones around 2011-07-10 and weak, but distinct ones, yesterday evening (2011-07-20T23:00Z+1) through thin clouds (only the Moon and the brightest stars were visible.)
Jul
19
comment Has a human ever perished in space?
@SB01: what is "that recent book"?
Jul
16
comment What is so special about iron?
Actually, nickel-62 is the most tightly bound nucleus (per nucleon) followed by iron-58 and iron-56. Practicalities apply, though.
Jul
13
comment Is there evidence of dark matter in our galaxy?
"distance clusters" -> "distant clusters"?
Jul
5
comment Exoplanet detection via space-based parasol
Can you move the first paragraph to a comment to Andrew's answer? This is not a forum.
Jul
4
comment How can a Population III star be so massive?
+1. That is an outstanding answer.
Jul
3
comment Applying the Maxwell–Boltzmann statistics to astrophysical objects
Re: "Can the Universe be considered in thermal equilibria?". Why equilibria? Why isn't it equilibrium?
Jun
17
comment How long would it take to scan the visible universe for unique signals?
More information about HUDF.
Jun
16
comment What possible science could we do during the 2012 Venus transit?
I observed the entire transit in 2004 using a 200 mm Cassegrain telescope with a mylar solar filter. I was lucky with the weather and was at the right latitude. The "black drop" effect was clearly visible both at ingress and egress. But it is a optical illusion (?).
Jun
2
comment Can any telescope be used for solar observing?
@Anna Karenina: no, you need a narrow-band filter. A 1.5 Å filter will do for prominences. They are somewhat cheaper than a hydrogen-alpha filter proper. See for instance Solar Observing, section "Solar Prominence Filters".
Jun
1
comment What tools do I need to track an orbit of a mystery object?
How fast was it moving? For example, how long time, approximately, did it take to cross the field of view? 10 seconds, 1 minute, 5 minutes?
Jun
1
comment Scientific value of timing total lunar occultations
Interesting. What is the hit rate on asteroid occultations? Has the Hipparcos data increased it to something more acceptable than 10% in the 1980s?
Nov
14
comment Amount of 2 amperage
Better always use "current" instead of "amperage", especially on a physics site.
Nov
14
comment Amount of 2 amperage
@shk: do you need to add i1 and i2 and reduce to the shortest form?
Nov
10
comment How are neutrons produced from cosmic ray particles?
How about some more specific tags? Like particle-radiation, hadron, baryon, neutron?
Nov
9
comment Can extra-solar gamma rays reach the Earth's surface?
I see no such link, only "No preview available". I may be geographically challenged.