Astroblog: Seeing Vesta at Opposition (March 2021)

Wednesday, February 24, 2021

Seeing Vesta at Opposition (March 2021)


The North-east horizon as seen from Adelaide at 23:00 ACDST (10:00 pm non-daylight saving time) showing the location of Vesta (click to embiggen) on Thursday, March 4, when Vesta is at opposition at its brightest.Similar views will be seen elsewhere in Australia at the equivalent local time.	The approximate binocular view of Vesta and the three prominent guide stars at 23:00 ACDST (10:00 pm non-daylight saving time) on Thursday, March 4. (click to embiggen, similar views will be seen elsewhere at the equivalent local time).

Black and white horizon chart facing east suitable for printing showing location of 4 Vesta as seen from Adelaide at 23:00 ACDST. Similar views will be seen elsewhere in Australia at the equivalent local time. Use the charts above to orient yourself get to the guide stars.	Black and white binocular chart suitable for printing showing the movement of 4 Vesta over the next 30 days. The large circle represents the field of view of 10x50 binoculars. Click to embiggen and print. Use the horizon chart to the left for orientation first.

.
The Asteroid 4 Vesta is one of the iconic minor planets, and one of two orbited by the Dawn spacecraft. At favorable oppositions Vesta is bright enough to be seen with the unaided eye under dark sky conditions. This year it gets to magnitude 5.8 (although the chart says 6.0) just over unaided eye visibility at dark sky sites. Not really visible from suburban skies, but it will be easily visible in binoculars and small telescopes.

This year is a reasonable opposition of Vesta on March 4, when it will reach a magnitude of 5.8 at its brightest with good guide stars. The next bright opposition is 22 August in 2022 (also magnitude 5.8) but there will be fewer good guide stars. And in May 2025 it will reach magnitude 5.6 with good guide stars.

This year Vesta has some excellent signposts to it, just before and just after opposition Vesta is in the tail of Leo the lion between the easily recognizable Denebola (ß Leonis, the second brightest star in Leo) And Chertan (Θ Leonis) which form the triangle marking the Lions tail with Denebola and Zosma.

In binoculars if you star hop about two binocular widths from Denebola to Chertan (the next brightest star) Vesta is between Chertan and the two next brightest stars 81 and 85 Leo (see binocular charts). Vesta is the brightest object aside from Chertan, 81 and 85 Leo and its movement from night to night easily seen.

Finding Vesta with the charts should be easy. Print them out and use with a red-light torch (or a standard torch with red cellophane over it) so as to not disturb your night vision.

Sadly just before opposition itself, the waxing Moon / full Moon will interfere significantly (although you should still be able to just see it in binoculars. However, at opposition and several days after opposition Vesta is still bright and easily seen. 3-7 March may be best.

Labels: 4 Vesta, binocular, telescope