Elqui Province
The Palomar twilight survey of 'Ayl\'o'chaxnim, Atiras, and comets
Bolin, B. T., Masci, F. J., Coughlin, M. W., Duev, D. A., Ivezić, Ž., Jones, R. L., Yoachim, P., Ahumada, T., Bhalerao, V., Choudhary, H., Contreras, C., Cheng, Y. -C., Copperwheat, C. M., Deshmukh, K., Fremling, C., Granvik, M., Hardegree-Ullman, K. K., Ho, A. Y. Q., Jedicke, R., Kasliwal, M., Kumar, H., Lin, Z. -Y., Mahabal, A., Monson, A., Neill, J. D., Nesvorný, D., Perley, D. A., Purdum, J. N., Quimby, R., Serabyn, E., Sharma, K., Swain, V.
Near-sun sky twilight observations allow for the detection of asteroid interior to the orbit of Venus (Aylos), the Earth (Atiras), and comets. We present the results of observations with the Palomar 48-inch telescope (P48)/Zwicky Transient Facility (ZTF) camera in 30 s r-band exposures taken during evening astronomical twilight from 2019 Sep 20 to 2022 March 7 and during morning astronomical twilight sky from 2019 Sep 21 to 2022 Sep 29. More than 46,000 exposures were taken in evening and morning astronomical twilight within 31 to 66 degrees from the Sun with an r-band limiting magnitude between 18.1 and 20.9. The twilight pointings show a slight seasonal dependence in limiting magnitude and ability to point closer towards the Sun, with limiting magnitude slightly improving during summer. In total, the one Aylo, (594913) 'Ayl\'o'chaxnim, and 4 Atiras, 2020 OV1, 2021 BS1, 2021 PB2, and 2021 VR3, were discovered in evening and morning twilight observations. Additional twilight survey discoveries also include 6 long-period comets: C/2020 T2, C/2020 V2, C/2021 D2, C/2021 E3, C/2022 E3, and C/2022 P3, and two short-period comets: P/2021 N1 and P/2022 P2 using deep learning comet detection pipelines. The P48/ZTF twilight survey also recovered 11 known Atiras, one Aylo, three short-period comes, two long-period comets, and one interstellar object. Lastly, the Vera Rubin Observatory will conduct a twilight survey starting in its first year of operations and will cover the sky within 45 degrees of the Sun. Twilight surveys such as those by ZTF and future surveys will provide opportunities for discovering asteroids inside the orbits of Earth and Venus.
Active learning with RESSPECT: Resource allocation for extragalactic astronomical transients
Kennamer, Noble, Ishida, Emille E. O., Gonzalez-Gaitan, Santiago, de Souza, Rafael S., Ihler, Alexander, Ponder, Kara, Vilalta, Ricardo, Moller, Anais, Jones, David O., Dai, Mi, Krone-Martins, Alberto, Quint, Bruno, Sreejith, Sreevarsha, Malz, Alex I., Galbany, Lluis
The recent increase in volume and complexity of available astronomical data has led to a wide use of supervised machine learning techniques. Active learning strategies have been proposed as an alternative to optimize the distribution of scarce labeling resources. However, due to the specific conditions in which labels can be acquired, fundamental assumptions, such as sample representativeness and labeling cost stability cannot be fulfilled. The Recommendation System for Spectroscopic follow-up (RESSPECT) project aims to enable the construction of optimized training samples for the Rubin Observatory Legacy Survey of Space and Time (LSST), taking into account a realistic description of the astronomical data environment. In this work, we test the robustness of active learning techniques in a realistic simulated astronomical data scenario. Our experiment takes into account the evolution of training and pool samples, different costs per object, and two different sources of budget. Results show that traditional active learning strategies significantly outperform random sampling. Nevertheless, more complex batch strategies are not able to significantly overcome simple uncertainty sampling techniques. Our findings illustrate three important points: 1) active learning strategies are a powerful tool to optimize the label-acquisition task in astronomy, 2) for upcoming large surveys like LSST, such techniques allow us to tailor the construction of the training sample for the first day of the survey, and 3) the peculiar data environment related to the detection of astronomical transients is a fertile ground that calls for the development of tailored machine learning algorithms.
Scientists are using satellites to spot stranded whales from SPACE
Satellites could help locate stranded whales more efficiently and in real-time. Scientists have begun harnessing the power of the technology's high-resolution imagery to detect and monitor whales stranded on the shore from space. The team noted that the use of satellites will help find stranded whales in remote locations, as well as spot potentially deteriorating ocean conditions. Satellites could help locate stranded whales more efficiently and in real-time. Scientists have begun harnessing the power of the technology's high-resolution imagery to detect and monitor whales stranded on the shore from space Chile witnessed one of the largest mass mortality of baleen whales in 2015 on the remote beaches of Patagonia – at least 343 died.
Unravelling the mystery of the 'Chilean Titanic'
Explorers have discovered the remains of the'Chilean Titanic' 95 years after it sank off the coast of Chile. The Itata ship sank in 1922 with more than 400 people on board, after running into a storm during a journey between the US and Chile. For the last seven years, experts have been searching for the wreckage, and have finally pinpointed it off the port of Coquimbo, in Elqui Province, in northern Chile. The researchers hope the discovery will help to complete the story of the infamous ship, and bring more tourists to the area. After seven years of searching, explorers have discovered the remains of the'Chilean Titanic' 95 years after it sank off the coast of Chile Researchers from the Catholic University of the North started looking for the wreckage in 2010.
Active Learning For Identifying Function Threshold Boundaries
Bryan, Brent, Nichol, Robert C., Genovese, Christopher R., Schneider, Jeff, Miller, Christopher J., Wasserman, Larry
We present an efficient algorithm to actively select queries for learning the boundaries separating a function domain into regions where the function is above and below a given threshold. We develop experiment selection methods based on entropy, misclassification rate, variance, and their combinations, and show how they perform on a number of data sets. We then show how these algorithms are used to determine simultaneously valid 1 α confidence intervals for seven cosmological parameters. Experimentation shows that the algorithm reduces the computation necessary for the parameter estimation problem by an order of magnitude.
Active Learning For Identifying Function Threshold Boundaries
Bryan, Brent, Nichol, Robert C., Genovese, Christopher R., Schneider, Jeff, Miller, Christopher J., Wasserman, Larry
We present an efficient algorithm to actively select queries for learning the boundaries separating a function domain into regions where the function is above and below a given threshold. We develop experiment selection methods based on entropy, misclassification rate, variance, and their combinations, and show how they perform on a number of data sets. We then show how these algorithms are used to determine simultaneously valid 1 α confidence intervals for seven cosmological parameters. Experimentation shows that the algorithm reduces the computation necessary for the parameter estimation problem by an order of magnitude.