ARI's "Geschichte des Fixsternhimmels" is an attempt to collect all
astrometrically useful observations from before ca. 1970 in a way
comparable to what has been done to construct the FK* series of
fundamental catalogs. About 7e6 published positions are included.
In GAVO's DC, we provide tables of identified and non-identified stars
together with the master catalog that objects were identified against.
The catalogue ARIHIP has been constructed by selecting the 'best
data' for a given star from combinations of HIPPARCOS data with Boss'
GC and/or the Tycho-2 catalogue as well as the FK6. It provides 'best
data' for 90 842 stars with a typical mean error of 0.89 mas/year
(about a factor of 1.3 better than Hipparcos for this sample of
stars).
Astrometric Microlensing Events Predicted from Gaia DR2
Short Name:
am lensing 2
Date:
23 Mar 2022 13:13:04
Publisher:
The GAVO DC team
Description:
From the Gaia DR2 catalogue we predict astrometric microlensing
events by foreground stars with high proper motion (µ_tot >150mas/yr)
passing a background source in the next decades. Using Gaia DR2
photometry we determine an approximate mass of the lens, which we use
to calculate the expected microlensing effects. This yields 3914
microlensing events by 2875 different lenses between 2010 and 2065
with expected shifts larger than 0.1 mas between the lensed and
unlensed positions of the source. 513 of those are expected to happen
between 2014.5 - 2026.5 and might be measured by Gaia. For 127 events
we also expect a magnification between 1 mmag and 3 mag.
Astrometric Microlensing Events Predicted from Gaia eDR3
Short Name:
am lensing 2
Date:
23 Mar 2022 13:13:11
Publisher:
The GAVO DC team
Description:
From the Gaia eDR3 catalogue we predict astrometric microlensing
events by foreground stars with high proper motion (μ > 100 mas/yr)
passing a background source in the next decades. Using Gaia DR3
photometry we determine an approximate mass of the lens, which we use
to calculate the expected microlensing effects. This yields 4842
microlensing events by 3791 different lenses between 2010 and 2066
with expected shifts larger than 0.1 mas between the lensed and
unlensed positions of the source. The past events might be interested
when analyzing the individual Gaia measurements). 685 of those are
expected to happen within the next decade (2021-2031). For 140 events
we also expect a magnification between 1 mmag and 0.6 mag.
This service queries the catalog of radio sources from the LOFAR
Two-metre Sky Survey First Data Release (LoTSS-DR1) that have been
cross-matched with an optical or infrared counterpart. This data
release contains images and catalogs that characterise the
low-frequency radio emission in the region of the HETDEX Spring Field
(right ascension 10h45m00s to15h30m00s and declination 45◦00′00′′ to
57◦00′00′′). A total of 325,694 radio sources are detected in a region
covering 424 square degrees. The maps have a median sensitivity of 71
uJy/beam and a resolution of 6 arcsec. Optical counterparts for 71% of
the radio sources have been identified and where possible photometric
redshifts for these sources have been derived.
This service queries the catalog of radio sources from the LOFAR
Two-metre Sky Survey First Data Release (LoTSS-DR1). This data release
contains images and catalogs that characterise the low-frequency radio
emission in the region of the HETDEX Spring Field (right ascension
10h45m00s to15h30m00s and declination 45◦00′00′′ to 57◦00′00′′). A
total of 325,694 radio sources are detected in a region covering 424
square degrees. The maps have a median sensitivity of 71 uJy/beam and
a resolution of 6 arcsec. Optical counterparts for 71% of the radio
sources have been identified and where possible photometric redshifts
for these sources have been derived.