Because of atmosphere's absorption, Ultraviolet (UV) radiation must be observed from space, which is much harder than ground observations. Because of this, we still knows quite little about UV spectrum of asteroids, which are usually classified according to their optical/IR spectra. Fortunately, Swift uniquely has the UV capability and time to measure UV spectra of ~20 asteroids. **Will their types keep the same in UV? Will there be some new trends? How will the results affect the understanding of the solar system?** We are extracting the spectra, let's look forward to the results!
What does the **first** known active **comet from another star** looks like? **2I/Borisov**, the comet, visited us in late 2019, and telescopes around the world observed it ~~to see if it an alien's spacecraft~~ to explore its properties. Our teams successfully used UVOT/Swift to measure its water, and COS/HST to measure its carbon monoxide. The interesting conclusions can be learned from the following buttons.
Observations are not easy, what an object should be and what it looks like in data are always quite different. There is no perfect technique and telescope, we have to do something to restore truths, which includes telescope calibration. For example, shapes of X-ray spectra can be changed during detection, to calibrate which response and redistribution files need to be calculated by comparing the observed spectra with other telescopes' data. That is what I did for an X-ray telescope.
How can we measure solar wind in high ecliptic latitudes? It is very hard to send a satellite there, and speculation is also difficult because solar wind changes rapidly during propagation. Here come comets! Comets can reach there! The interaction SWCX between comets and solar wind can tell us a lot about solar wind, comets' coma, and even atomic physics. HKU has a great opportunity to launch a satellite to observe SWCX in EUV band. I analysed SWCX for 5 comets in X-ray band and predicted EUV spectra for the satellite design.