Informationen rund um das Beobachten

Wetterstationen

Satellitenbilder: Uni Karlsruhe
Satellitenbilder: sat24.com
Niederschlagsradar: niederschlagsradar.de, wetter.com






Wetter online: Profi Wetter online (Niederschlagsart ME)
Wetterzentrale: www.wetterzentrale.de
MPI-BGC: http://www.bgc-jena.mpg.de/wetter/
Meteoblue: Meteoblue (Jena)






GSH Messwerte: klick mich






MSN Wetter (Jena): http://wetter.msn.com, msn wetterkarten
AccuWeather (GSH): http://www.accuweather.com


Ephemeriden

Auf- und Untergangszeiten sind unter dem Link "Weitere ...daten" zu finden.

Planeten Ephemeriden

(Quelle: ephemeriden.com)

Photometric Standard Stars


Thanks to Thomas Eisenbeiß for this section.


Standard Photometric Sequences

The link above leads to an Acrobat file in PDF format which lists the coordinates for the fields, the field sizes, and the numbers of standards in each field. Many of these fields are based on the Landolt standards.


Standard Photometric Sequences (Landolt et al.)

LONEOS Quasi-Standards

 

These are fields which contain standard stars for BVRI photometry. Observations of such standards are required to derive standard magnitudes and colors. These fields may also be used to determine the faintest magnitudes recorded in an image (limiting magnitudes). This is a preliminary list. The fields are still not ideal and we need suitable standard star fields with declinations above 10 degree. All observers are asked to look for such fields and to add this information to this list.
Please e-mail to Thomas Eisenbeiß

The following table lists some examples of some Landolt fields. The standards in these fields are on the UBVRI system of Landolt (Cousins-Johnson).

 

Field
RA
(2000)
DEC
(2000)
Size
(arcmin)
mag. range
num. stars
Comments
SA 98
data

6h 52m 05s

-00o 19' 40"
20
9-15
46

Most of the standards should fit in a 20 arcminute image. The coordinates are for star 98-650.

SA 100
data

8h 53m 19s

-00o 41' 10"
20
9-13
5

All the standards should fit in a 20 arcminute image. The coordinates are for star 100-269

PG0918+029
data

9h 21m 34s

+02o 48' 01"
5
12-14
5

The field is about 5 arcminutes and will easily fit in a 20 arcminute image. The coordinates are for star B. The field is not crowded and has an excellent range in color.

SA 101
data

9h 56m 21s

-00o 27' 19"
20-60
10-16
35

The distance between star L5 and star 330 is approximately 12 arcminutes. The coordinates given are for star 101-330.

SA 104
data

12h 42m 54s

-00o 32' 06"
20-60
10-16
28

A line representing 10 arcminutes is shown in the image. The coordinates given are for star 104-456.

SA 104E
data

12h 43m 59s

-00o 33' 36"
20-60
10-16
11

A line representing 10 arcminutes is shown in the image. The coordinates given are for star 104-367.

SA 107
data

15h 39m 19s

-00o 15' 29"
20-60
10-16
28

A line representing 10 arcminutes is shown in the image. The coordinates given are for star 107-602.

PG1633+099
data

16h 35m 34s

+09o 46' 22"
5
12-15
5

The field is about 5 arcminutes and will easily fit in a 20 arcminute image. The coordinates are for star B. The field has an excellent range in color.

PG1657+078
data

16h 59m 32s

+07o 43' 31"
5
14-15.2
4

A line representing 5 arcminutes is shown in the image. The coordinates are for the source PG1657+078. There is apparently no data available for star D, so there are really only 3 standards in this field.

SA 110
data

18h 42m 19s

+00o 08' 24"
20
10-16
12

A line representing 10 arcminutes is shown in the image. The coordinates given are for star 110-355

SA 110N
data

18h 43m 11s

+00o 29' 43"
30
11-15
10

This clustering of stars on the north side of the SA 110 field is approximately 10 arcminutes across. The coordinates given are for star 110-503. This grouping seems slightly brighter than the average for SA 110 and seems to have a reasonable range in color.

SA 113
data

21h 42m 35s

+00o 16' 46"
20
10-16
16

A line representing 10 arcminutes is shown in the image. The coordinates given are for star 113-163. These coordinates should center a small clustering of approximately 7 standards on the east side of the field. This grouping has a modest range in color.

The links on the field names are to finding charts on which the standards are identified. In these charts north is up and east is to the left. Unfortunately, the scale is slightly different for each chart. A guide to the scale and some comments for each of the finding charts is given in the table.

 

The sizes of many of the Landolt fields are technically about 60 minutes of arc, but the standards tend to be concentrated in smaller regions within the field. A field size of 20 minutes of arc can generally be positioned to accomodate a large fraction of the total number of standards in each field. The coordinates that are given in the table were selected to be in the central region for each concentration of standards. Several of the Landolt fields are small at only about 5 minutes of arc on a side. These smaller fields typically only have about 5 stars, but they often cover an excellent range in color.

The "data" link under the name of the field will display the data for the standard stars identified in the field. The data available includes precise coordinates for 2000.0 along with the magnitudes and colors for the standards. The detailed description and format for this data is available in the Landolt Data Format file.

The full list of landolt standard stars is available on the web and as local copy.

Landolt has published several articles related to this project.

Landolt, A. U.; AJ 104, 340-371 and 436-491 (finding charts) 1992
This article also describes the technical specifications that define the instrumental magnitude system used by Landolt. This defines the Landolt system, although the published magnitudes and colors have been transformed to the standard Johnson-Cousins UBVRI system. The "Landolt system" is now the defacto standard for UBVRI photometry.

Landolt, A. U.; AJ 78, 959-981 and 989-1020 (finding charts) 1973

This is the first paper in the series. This paper defines the primary Landolt fields, but only includes data for UBV photometry.

 

 

The LONEOS Quasi-standards

Note that the above link is to an FTP server that will download the LONEOS Catalog to your browser. The catalog is simply a list of star names, precise coordinates, and reported photometry. The list is sorted by coordinates. The literature references on which the catalog is based are also available

Brian Skiff of Lowell Observatory continues to compile published (and unpublished) observations which could be considered "secondary standards" or quasi-standards. This is the LONEOS Catalog. Observations are merely compiled from the literature. Data is taken from published papers as reported by the original authors as being used as secondary standards in the fields where they were working. This catalog is obviously not necessarily on a homogeneous photometric system such as provided by the Landolt and Stetson standards. However, if you are desperate (and lucky) you may find that someone has already attempted to establish standard magnbitudes and colors for a star that happens to be in your field. A local copy of the LONEOS Catalog is available.

for further information see homepage of the sonoma state university observatory

send comments and suggestions to Thomas Eisenbeiß