Gaia Newsletter #29 - Gaia
News 2023
Gaia Newsletter #29
Compilation of news and updates from the Gaia mission since mid October 2023.
Vacancy notice for Gaia Project Scientist position
At the European Space Agency, there is an opening for the position Gaia project scientist. The vacancy notice can be found here from the ESA jobs website. Deadline for the application is 6 November. The location for this position would be either ESAC (Madrid, Spain) or ESTEC (Noordwijk, The Netherlands).
Full details regarding the profile can be found from the vacancy notice: https://jobs.esa.int/job/Noordwijk-Project-Scientist/994659001/
Gaia Focused Product Release Known issues
A Gaia FPR known issue was added recently on the topic of solar system objects: Error in the description field of epoch_state_vector of gaiafpr.sso_source. In the description of the field epoch_state_vector of the sso_source table, the origin of the epoch is wrongly given as JD2457907.5 TCB. The correct value is JD2455197.5 TCB (1 January 2010.0). This will be corrected in the future in our data model and documentation. Once corrected there, we will update this known issue accordingly.
Gaia scanning law published for the full operational mission period
The Gaia scanning law pointings for the data collection period underlying Gaia (E)DR3 are available from the Gaia ESA Archive in a table named "gaiadr3.commanded_scan_law". Here we provide an additional and complementary data set, namely the commanded scanning law pointings over the full mission interval (from 2014-07-25 10:31:26 TCB to 2025-06-30 23:59:56 TCB), including the Ecliptic Pole Scanning at the beginning of the mission. As in the case of the Gaia (E)DR3 table, the data presented here contains the attitude as commanded in the past and as currently planned to be commanded in the future. The actually realised attitude of the spacecraft could deviate from it by up to about 30 arcsec. The time interval, in particular the end date in summer 2025, is excepted to contain the full operational mission period. Obviously, the precise end of spacecraft operations is not yet defined. Find full details here.
Stories on Gaia Cosmos
The following stories have been published on Gaia Cosmos since the last newsletter:
Gaia Data Release 3 known issues
A Gaia DR3 known issue was added recently on the topic of Documentation: "Photometric Relations - Typo in the filtering table". In the Gaia data release 3 documentation, there is a typo in Table 5.6 included in Section 5.5.1 (Photometric relationships with other photometric systems). Table 5.6 includes the filters applied to the data used to derive the photometric relationships between Gaia passbands and other passbands from some common photometric systems. In particular, the typo is present in the relationship between Gaia passbands and the z SDSS filter. The last line in Table 5.6 indicates that the selected stars to produce G - z = f (GBP - GRP) relationship have G - z < 0.7 (GBP - GRP) - 0.7, but instead the "<" sign should be a ">" sign.
Thus, the last line of the table should be substituted by:
G - z > 0.7 ( GBP - GRP ) - 0.7
This typo has no further impact on the rest of the section (relationships, range of applicability, and figures).
Gaia Data Release 2 known issues
A Gaia DR2 known issue was added recently on the topic of astrophysical parameters: "Error in low-temperature BCG polynomial coefficients". Table 4 in Andrae et al. (2018) provides polynomial coefficients that define the dependence of the bolometric correction in the Gaia DR2 G band (BCG) on stellar effective temperature (see Equation 7). The coefficients for the low-temperature regime (3300-4000 K) are wrong and do not reproduce Figure 8 in the same paper. The correct coefficients for the range Teff = 3300 - 4000 K are:
BCG | sigma(BCG) | |
---|---|---|
a0 | -36.4842 | 23.5002 |
a1 | -0.0618011 | 0.0377316 |
a2 | -3.83144E-05 | 2.18840E-05 |
a3 | -1.01823E-08 | 5.40373E-09 |
a4 | -1.00231E-12 | 4.82925E-13 |
The reported coefficients for the 4000 - 8000 K range are correct. Users are in any case advised to use the Gaia DR3 photometry and the associated bolometric correction tool provided at https://www.cosmos.esa.int/web/gaia/dr3-bolometric-correction-tool.
Did you know...
- Some technical documents by the Gaia Data Processing and Analysis Consortium are available here?
- Gaia orbits the Lagrange point L2? Which means Gaia is at a distance of 1,5 million kms from Earth?
- Images suitable for printing as posters are available from this page?
- Gaia is almost 10 years in space?
- Removed a total of (1) style text-align:center;
- Removed a total of (1) style text-align:left;
- Removed a total of (7) style text-align:justify;
- Removed a total of (1) align=center.
- Removed a total of (1) border attribute.
- Removed a total of (1) cellpadding attribute.
- Removed a total of (1) style display:none;