UCSB Astrophysics

The sky over Broida Hall. Looking south across the Santa Barbara Channel.

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LST
 

Tonight

§ 01Sky tonight

Research targets up tonight

Objects the group has studied that rise above the horizon at Broida Hall during tonight's dark hours, by research theme. Times are Pacific.

Rise and set times are computed in your browser for tonight at Broida Hall.

Exoplanets & instruments

Stars, explosions & transients

Black holes & gravitational waves

Galaxies & the gas around them

Cosmic dawn

Experimental cosmology

Gravitational wave events 22 events, 4 drawn on the sky

Most events have no point position, only a region of the sky that holds the source with 90% probability. Regions of 300 deg² or less are drawn on the sky above; the GW button shows or hides them.

§ 02Notes

How the sky is drawn

The view
You look south from Broida Hall, with the center of the view 30° above the horizon. Drag the sky, or use the arrow keys, to turn between east and west. The view is 76° to 120° wide, depending on your screen.
Projection
The sky is drawn in stereographic projection. Circles on the sky stay circles on the screen, so constellations keep their shapes, and the scale grows toward the edges.
Positions
Astronomy Engine computes the Sun, Moon and planets in your browser for the time shown. Star positions are precessed from J2000 to that date, and refraction lifts objects near the horizon. The Sun and Moon are drawn three times their real size, so the Moon's phase can be read.
Stars
Stars to magnitude 6, constellation lines and the outline of the Milky Way come from d3-celestial. Star colors follow the B−V color index. Stars fade near the horizon, by 0.2 magnitudes per airmass, and in twilight and moonlight.
Horizon
The Channel Islands sit on the sea horizon at their real azimuths, with their heights drawn three times too tall so they can be seen. The mainland coast runs along either side.
Time
Tonight sets the clock to 30 minutes after astronomical twilight ends. The slider runs from noon to noon, Pacific time, and Play turns the sky at one hour per second. Add ?t= and an ISO time to the address to fix the time.
Targets
Gold reticles mark objects the group has studied. The ones with the most papers carry labels. Hover over or focus a reticle to name the others, and select it for its papers.