Tess captures comet, variable stars, asteroids, and Martian light

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During its testing period prior to beginning science operations this month, the exoplanet space telescope TESS spotted in one series of images a comet, a host of variable stars, some asteroids, and even the faint hint of some reflected light from Mars.

Over the course of these tests, TESS took images of C/2018 N1, a comet discovered by NASA’s Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) satellite on June 29. The comet, located about 29 million miles (48 million kilometers) from Earth in the southern constellation Piscis Austrinus, is seen to move across the frame from right to left as it orbits the Sun. The comet’s tail, which consists of gases carried away from the comet by an outflow from the Sun called the solar wind, extends to the top of the frame and gradually pivots as the comet glides across the field of view.

In addition to the comet, the images reveal a treasure trove of other astronomical activity. The stars appear to shift between white and black as a result of image processing. The shift also highlights variable stars — which change brightness either as a result of pulsation, rapid rotation, or by eclipsing binary neighbors. Asteroids in our solar system appear as small white dots moving across the field of view. Towards the end of the video, one can see a faint broad arc of light moving across the middle section of the frame from left to right. This is stray light from Mars, which is located outside the frame. The images were taken when Mars was at its brightest near opposition, or its closest distance, to Earth.

The video that was compiled from these images is embedded below the fold.


One comment

  • Localfluff

    ST Kepler’s little field of view was “polluted” by asteroids and comets, and who knows what, passing by. They couldn’t be tracked. When they passed near a star it looked like something of a transit or stellar variability and generated false alarms that had to be sorted out manually. TESS with its narrow but 90 degrees tall field of view should be able to make useful orbital determinations of those that move across close enough along the right general direction.

    Transiting exoplanet observatories also give lots of data about stellar variability. Something which I fear is a bit neglected, considering that Apollo is still our God, whether one believe in him or not, he won’t leave his throne in the sky. We’re the victims, and children, of his temper.

    I think that TESS has been underestimated by the general space enthusiast community. Because it is European and they have lousy science marketing. But this will get the whole exoplanet fever going again, I bet! Might be a good idea to prepare blogging alot about this in the coming months and years, Robert. And TESS observes the nearest brightest stars, so it might spur amateur astronomy too. Every child will soon learn that for example that star there in Orion has an Earth like planet.

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